Remove twi library and switch to i2c library submodule
This commit is contained in:
parent
04af54e7c8
commit
2768009720
253
rtc.cpp
253
rtc.cpp
@ -73,6 +73,11 @@
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#define TRUE 1
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#define TRUE 1
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#define FALSE 0
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#define FALSE 0
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#include "../clock.hpp"
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#include "../i2c/i2c.hpp"
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using i2c_t = i2c::I2c<i2c::Hardware<100'000>>;
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#include "rtc.h"
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#include "rtc.h"
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#define RTC_ADDR 0x68 // I2C address
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#define RTC_ADDR 0x68 // I2C address
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@ -93,20 +98,23 @@ uint8_t bcd2dec(uint8_t b)
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uint8_t rtc_read_byte(uint8_t offset)
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uint8_t rtc_read_byte(uint8_t offset)
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{
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{
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(offset);
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i2c_t::write(offset);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 1);
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i2c_t::start<RTC_ADDR>(true);
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return twi_receive();
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const auto received = i2c_t::read<true>();
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i2c_t::stop();
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return received;
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}
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}
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void rtc_write_byte(uint8_t b, uint8_t offset)
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void rtc_write_byte(uint8_t b, uint8_t offset)
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{
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{
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(offset);
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i2c_t::write(offset);
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twi_send_byte(b);
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i2c_t::write(b);
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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static bool s_is_ds1307 = false;
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static bool s_is_ds1307 = false;
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@ -114,6 +122,8 @@ static bool s_is_ds3231 = false;
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void rtc_init(void)
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void rtc_init(void)
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{
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{
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i2c_t::init();
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// Attempt autodetection:
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// Attempt autodetection:
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// 1) Read and save temperature register
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// 1) Read and save temperature register
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// 2) Write a value to temperature register
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// 2) Write a value to temperature register
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@ -153,17 +163,13 @@ struct rtc_tm* rtc_get_time(void)
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// read 7 bytes starting from register 0
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// read 7 bytes starting from register 0
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// sec, min, hour, day-of-week, date, month, year
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// sec, min, hour, day-of-week, date, month, year
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0);
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i2c_t::write(0x0);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 7);
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i2c_t::start<RTC_ADDR>(true);
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i2c_t::readBytes<7>(rtc);
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for (uint8_t i = 0; i < 7; i++) {
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i2c_t::stop();
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rtc[i] = twi_receive();
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}
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twi_end_transmission();
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// Clear clock halt bit from read data
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// Clear clock halt bit from read data
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// This starts the clock for a DS1307, and has no effect for a DS3231
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// This starts the clock for a DS1307, and has no effect for a DS3231
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@ -198,17 +204,13 @@ void rtc_get_time_s(uint8_t* hour, uint8_t* min, uint8_t* sec)
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// read 7 bytes starting from register 0
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// read 7 bytes starting from register 0
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// sec, min, hour, day-of-week, date, month, year
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// sec, min, hour, day-of-week, date, month, year
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0);
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i2c_t::write(0x0);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 7);
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i2c_t::start<RTC_ADDR>(true);
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i2c_t::readBytes<7>(rtc);
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for(uint8_t i=0; i<7; i++) {
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i2c_t::stop();
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rtc[i] = twi_receive();
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}
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twi_end_transmission();
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if (sec) *sec = bcd2dec(rtc[0]);
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if (sec) *sec = bcd2dec(rtc[0]);
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if (min) *min = bcd2dec(rtc[1]);
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if (min) *min = bcd2dec(rtc[1]);
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@ -218,8 +220,8 @@ void rtc_get_time_s(uint8_t* hour, uint8_t* min, uint8_t* sec)
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// fixme: support 12-hour mode for setting time
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// fixme: support 12-hour mode for setting time
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void rtc_set_time(struct rtc_tm* tm_)
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void rtc_set_time(struct rtc_tm* tm_)
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{
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{
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0);
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i2c_t::write(0x0);
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uint8_t century;
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uint8_t century;
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if (tm_->year > 2000) {
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if (tm_->year > 2000) {
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@ -231,28 +233,28 @@ void rtc_set_time(struct rtc_tm* tm_)
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}
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}
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// clock halt bit is 7th bit of seconds: this is always cleared to start the clock
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// clock halt bit is 7th bit of seconds: this is always cleared to start the clock
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twi_send_byte(dec2bcd(tm_->sec)); // seconds
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i2c_t::write(dec2bcd(tm_->sec)); // seconds
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twi_send_byte(dec2bcd(tm_->min)); // minutes
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i2c_t::write(dec2bcd(tm_->min)); // minutes
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twi_send_byte(dec2bcd(tm_->hour)); // hours
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i2c_t::write(dec2bcd(tm_->hour)); // hours
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twi_send_byte(dec2bcd(tm_->wday)); // day of week
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i2c_t::write(dec2bcd(tm_->wday)); // day of week
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twi_send_byte(dec2bcd(tm_->mday)); // day
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i2c_t::write(dec2bcd(tm_->mday)); // day
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twi_send_byte(dec2bcd(tm_->mon) + century); // month
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i2c_t::write(dec2bcd(tm_->mon) + century); // month
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twi_send_byte(dec2bcd(tm_->year)); // year
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i2c_t::write(dec2bcd(tm_->year)); // year
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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void rtc_set_time_s(uint8_t hour, uint8_t min, uint8_t sec)
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void rtc_set_time_s(uint8_t hour, uint8_t min, uint8_t sec)
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{
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{
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0);
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i2c_t::write(0x0);
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// clock halt bit is 7th bit of seconds: this is always cleared to start the clock
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// clock halt bit is 7th bit of seconds: this is always cleared to start the clock
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twi_send_byte(dec2bcd(sec)); // seconds
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i2c_t::write(dec2bcd(sec)); // seconds
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twi_send_byte(dec2bcd(min)); // minutes
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i2c_t::write(dec2bcd(min)); // minutes
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twi_send_byte(dec2bcd(hour)); // hours
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i2c_t::write(dec2bcd(hour)); // hours
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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// DS1307 only (has no effect when run on DS3231)
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// DS1307 only (has no effect when run on DS3231)
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@ -296,16 +298,14 @@ void ds3231_get_temp_int(int8_t* i, uint8_t* f)
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if (s_is_ds1307) return; // only valid on DS3231
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if (s_is_ds1307) return; // only valid on DS3231
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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// temp registers 0x11 and 0x12
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// temp registers 0x11 and 0x12
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twi_send_byte(0x11);
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i2c_t::write(0x11);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 2);
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i2c_t::start<RTC_ADDR>(true);
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msb = i2c_t::read(); // integer part (in twos complement)
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if (twi_available()) {
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lsb = i2c_t::read<true>(); // fraction part
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msb = twi_receive(); // integer part (in twos complement)
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lsb = twi_receive(); // fraction part
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// integer part in entire byte
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// integer part in entire byte
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*i = msb;
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*i = msb;
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@ -315,38 +315,40 @@ void ds3231_get_temp_int(int8_t* i, uint8_t* f)
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// float value can be read like so:
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// float value can be read like so:
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// float temp = ((((short)msb << 8) | (short)lsb) >> 6) / 4.0f;
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// float temp = ((((short)msb << 8) | (short)lsb) >> 6) / 4.0f;
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}
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}
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}
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void rtc_force_temp_conversion(uint8_t block)
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void rtc_force_temp_conversion(uint8_t block)
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{
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{
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if (s_is_ds1307) return; // only valid on DS3231
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if (s_is_ds1307) return; // only valid on DS3231
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// read control register (0x0E)
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// read control register (0x0E)
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0E);
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i2c_t::write(0x0E);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 1);
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i2c_t::start<RTC_ADDR>(true);
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uint8_t ctrl = twi_receive();
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uint8_t ctrl = i2c_t::read<true>();
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i2c_t::stop();
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ctrl |= 0b00100000; // Set CONV bit
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ctrl |= 0b00100000; // Set CONV bit
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// write new control register value
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// write new control register value
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0E);
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i2c_t::write(0x0E);
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twi_send_byte(ctrl);
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i2c_t::write(ctrl);
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twi_end_transmission();
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i2c_t::stop();
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if (!block) return;
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if (!block) return;
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// Temp conversion is ready when control register becomes 0
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// Temp conversion is ready when control register becomes 0
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do {
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do {
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// Block until CONV is 0
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// Block until CONV is 0
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0E);
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i2c_t::write(0x0E);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 1);
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} while ((twi_receive() & 0b00100000) != 0);
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i2c_t::start<RTC_ADDR>(true);
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// HACK: Missing stop after read, might still work though
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} while ((i2c_t::read<true>() & 0b00100000) != 0);
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}
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}
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@ -371,32 +373,35 @@ void rtc_set_sram(uint8_t *data)
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uint8_t rtc_get_sram_byte(uint8_t offset)
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uint8_t rtc_get_sram_byte(uint8_t offset)
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{
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{
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(DS1307_SRAM_ADDR + offset);
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i2c_t::write(DS1307_SRAM_ADDR + offset);
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twi_end_transmission();
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i2c_t::stop();
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twi_request_from(RTC_ADDR, 1);
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i2c_t::start<RTC_ADDR>(true);
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return twi_receive();
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const auto received = i2c_t::read<true>();
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i2c_t::stop();
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return received;
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}
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}
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void rtc_set_sram_byte(uint8_t b, uint8_t offset)
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void rtc_set_sram_byte(uint8_t b, uint8_t offset)
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{
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{
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(DS1307_SRAM_ADDR + offset);
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i2c_t::write(DS1307_SRAM_ADDR + offset);
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twi_send_byte(b);
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i2c_t::write(b);
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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void rtc_SQW_enable(bool enable)
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void rtc_SQW_enable(bool enable)
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{
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{
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if (s_is_ds1307) {
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if (s_is_ds1307) {
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x07);
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i2c_t::write(0x07);
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twi_end_transmission();
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i2c_t::stop();
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// read control
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// read control
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twi_request_from(RTC_ADDR, 1);
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i2c_t::start<RTC_ADDR>(true);
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uint8_t control = twi_receive();
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uint8_t control = i2c_t::read<true>();
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i2c_t::stop();
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if (enable)
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if (enable)
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control |= 0b00010000; // set SQWE to 1
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control |= 0b00010000; // set SQWE to 1
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@ -404,20 +409,21 @@ void rtc_SQW_enable(bool enable)
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control &= ~0b00010000; // set SQWE to 0
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control &= ~0b00010000; // set SQWE to 0
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// write control back
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// write control back
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x07);
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i2c_t::write(0x07);
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twi_send_byte(control);
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i2c_t::write(control);
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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else { // DS3231
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else { // DS3231
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0E);
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i2c_t::write(0x0E);
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twi_end_transmission();
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i2c_t::stop();
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// read control
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// read control
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twi_request_from(RTC_ADDR, 1);
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i2c_t::start<RTC_ADDR>(true);
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uint8_t control = twi_receive();
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uint8_t control = i2c_t::read<true>();
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i2c_t::stop();
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if (enable) {
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if (enable) {
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control |= 0b01000000; // set BBSQW to 1
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control |= 0b01000000; // set BBSQW to 1
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@ -428,51 +434,53 @@ void rtc_SQW_enable(bool enable)
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}
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}
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// write control back
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// write control back
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0E);
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i2c_t::write(0x0E);
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twi_send_byte(control);
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i2c_t::write(control);
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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}
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}
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void rtc_SQW_set_freq(enum RTC_SQW_FREQ freq)
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void rtc_SQW_set_freq(enum RTC_SQW_FREQ freq)
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{
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{
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if (s_is_ds1307) {
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if (s_is_ds1307) {
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x07);
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i2c_t::write(0x07);
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twi_end_transmission();
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i2c_t::stop();
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// read control (uses bits 0 and 1)
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// read control (uses bits 0 and 1)
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twi_request_from(RTC_ADDR, 1);
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i2c_t::start<RTC_ADDR>(true);
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uint8_t control = twi_receive();
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uint8_t control = i2c_t::read<true>();
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i2c_t::stop();
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control &= ~0b00000011; // Set to 0
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control &= ~0b00000011; // Set to 0
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control |= freq; // Set freq bitmask
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control |= freq; // Set freq bitmask
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// write control back
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// write control back
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x07);
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i2c_t::write(0x07);
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twi_send_byte(control);
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i2c_t::write(control);
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twi_end_transmission();
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i2c_t::stop();
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}
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}
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else { // DS3231
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else { // DS3231
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twi_begin_transmission(RTC_ADDR);
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i2c_t::start<RTC_ADDR>(false);
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twi_send_byte(0x0E);
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i2c_t::write(0x0E);
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twi_end_transmission();
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i2c_t::stop();
|
||||||
|
|
||||||
// read control (uses bits 3 and 4)
|
// read control (uses bits 3 and 4)
|
||||||
twi_request_from(RTC_ADDR, 1);
|
i2c_t::start<RTC_ADDR>(true);
|
||||||
uint8_t control = twi_receive();
|
uint8_t control = i2c_t::read<true>();
|
||||||
|
i2c_t::stop();
|
||||||
|
|
||||||
control &= ~0b00011000; // Set to 0
|
control &= ~0b00011000; // Set to 0
|
||||||
control |= (freq << 4); // Set freq bitmask
|
control |= (freq << 4); // Set freq bitmask
|
||||||
|
|
||||||
// write control back
|
// write control back
|
||||||
twi_begin_transmission(RTC_ADDR);
|
i2c_t::start<RTC_ADDR>(false);
|
||||||
twi_send_byte(0x0E);
|
i2c_t::write(0x0E);
|
||||||
twi_send_byte(control);
|
i2c_t::write(control);
|
||||||
twi_end_transmission();
|
i2c_t::stop();
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
@ -480,13 +488,14 @@ void rtc_osc32kHz_enable(bool enable)
|
|||||||
{
|
{
|
||||||
if (!s_is_ds3231) return;
|
if (!s_is_ds3231) return;
|
||||||
|
|
||||||
twi_begin_transmission(RTC_ADDR);
|
i2c_t::start<RTC_ADDR>(false);
|
||||||
twi_send_byte(0x0F);
|
i2c_t::write(0x0F);
|
||||||
twi_end_transmission();
|
i2c_t::stop();
|
||||||
|
|
||||||
// read status
|
// read status
|
||||||
twi_request_from(RTC_ADDR, 1);
|
i2c_t::start<RTC_ADDR>(true);
|
||||||
uint8_t status = twi_receive();
|
uint8_t status = i2c_t::read<true>();
|
||||||
|
i2c_t::stop();
|
||||||
|
|
||||||
if (enable)
|
if (enable)
|
||||||
status |= 0b00001000; // set to 1
|
status |= 0b00001000; // set to 1
|
||||||
@ -494,10 +503,10 @@ void rtc_osc32kHz_enable(bool enable)
|
|||||||
status &= ~0b00001000; // Set to 0
|
status &= ~0b00001000; // Set to 0
|
||||||
|
|
||||||
// write status back
|
// write status back
|
||||||
twi_begin_transmission(RTC_ADDR);
|
i2c_t::start<RTC_ADDR>(false);
|
||||||
twi_send_byte(0x0F);
|
i2c_t::write(0x0F);
|
||||||
twi_send_byte(status);
|
i2c_t::write(status);
|
||||||
twi_end_transmission();
|
i2c_t::stop();
|
||||||
}
|
}
|
||||||
|
|
||||||
// Alarm functionality
|
// Alarm functionality
|
||||||
|
|||||||
1
rtc.h
1
rtc.h
@ -18,7 +18,6 @@
|
|||||||
|
|
||||||
#include <stdbool.h>
|
#include <stdbool.h>
|
||||||
#include <avr/io.h>
|
#include <avr/io.h>
|
||||||
#include "twi.h"
|
|
||||||
|
|
||||||
#define DS1307_SLAVE_ADDR 0b11010000
|
#define DS1307_SLAVE_ADDR 0b11010000
|
||||||
|
|
||||||
|
|||||||
479
twi-lowlevel.cpp
479
twi-lowlevel.cpp
@ -1,479 +0,0 @@
|
|||||||
/*
|
|
||||||
twi.c - TWI/I2C library for Wiring & Arduino
|
|
||||||
Copyright (c) 2006 Nicholas Zambetti. All right reserved.
|
|
||||||
|
|
||||||
This library is free software; you can redistribute it and/or
|
|
||||||
modify it under the terms of the GNU Lesser General Public
|
|
||||||
License as published by the Free Software Foundation; either
|
|
||||||
version 2.1 of the License, or (at your option) any later version.
|
|
||||||
|
|
||||||
This library is distributed in the hope that it will be useful,
|
|
||||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
||||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
||||||
Lesser General Public License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU Lesser General Public
|
|
||||||
License along with this library; if not, write to the Free Software
|
|
||||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
||||||
*/
|
|
||||||
|
|
||||||
#include <math.h>
|
|
||||||
#include <stdlib.h>
|
|
||||||
#include <inttypes.h>
|
|
||||||
#include <avr/io.h>
|
|
||||||
#include <avr/interrupt.h>
|
|
||||||
#include <compat/twi.h>
|
|
||||||
|
|
||||||
#ifndef cbi
|
|
||||||
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#ifndef sbi
|
|
||||||
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#include "twi-lowlevel.h"
|
|
||||||
|
|
||||||
static volatile uint8_t twi_state;
|
|
||||||
static uint8_t twi_slarw;
|
|
||||||
|
|
||||||
static void (*twi_onSlaveTransmit)(void);
|
|
||||||
static void (*twi_onSlaveReceive)(uint8_t*, int);
|
|
||||||
|
|
||||||
static uint8_t twi_masterBuffer[TWI_BUFFER_LENGTH];
|
|
||||||
static volatile uint8_t twi_masterBufferIndex;
|
|
||||||
static uint8_t twi_masterBufferLength;
|
|
||||||
|
|
||||||
static uint8_t twi_txBuffer[TWI_BUFFER_LENGTH];
|
|
||||||
static volatile uint8_t twi_txBufferIndex;
|
|
||||||
static volatile uint8_t twi_txBufferLength;
|
|
||||||
|
|
||||||
static uint8_t twi_rxBuffer[TWI_BUFFER_LENGTH];
|
|
||||||
static volatile uint8_t twi_rxBufferIndex;
|
|
||||||
|
|
||||||
static volatile uint8_t twi_error;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_init
|
|
||||||
* Desc readys twi pins and sets twi bitrate
|
|
||||||
* Input none
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_init(void)
|
|
||||||
{
|
|
||||||
// initialize state
|
|
||||||
twi_state = TWI_READY;
|
|
||||||
|
|
||||||
#if defined(__AVR_ATmega168__) || defined(__AVR_ATmega8__) || defined(__AVR_ATmega328P__)
|
|
||||||
// activate internal pull-ups for twi
|
|
||||||
// as per note from atmega8 manual pg167
|
|
||||||
sbi(PORTC, 4);
|
|
||||||
sbi(PORTC, 5);
|
|
||||||
#else
|
|
||||||
// activate internal pull-ups for twi
|
|
||||||
// as per note from atmega128 manual pg204
|
|
||||||
sbi(PORTD, 0);
|
|
||||||
sbi(PORTD, 1);
|
|
||||||
#endif
|
|
||||||
|
|
||||||
// initialize twi prescaler and bit rate
|
|
||||||
cbi(TWSR, TWPS0);
|
|
||||||
cbi(TWSR, TWPS1);
|
|
||||||
TWBR = ((F_CPU / TWI_FREQ) - 16) / 2;
|
|
||||||
|
|
||||||
/* twi bit rate formula from atmega128 manual pg 204
|
|
||||||
SCL Frequency = CPU Clock Frequency / (16 + (2 * TWBR))
|
|
||||||
note: TWBR should be 10 or higher for master mode
|
|
||||||
It is 72 for a 16mhz Wiring board with 100kHz TWI */
|
|
||||||
|
|
||||||
// enable twi module, acks, and twi interrupt
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA);
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_slaveInit
|
|
||||||
* Desc sets slave address and enables interrupt
|
|
||||||
* Input none
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_setAddress(uint8_t address)
|
|
||||||
{
|
|
||||||
// set twi slave address (skip over TWGCE bit)
|
|
||||||
TWAR = address << 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_readFrom
|
|
||||||
* Desc attempts to become twi bus master and read a
|
|
||||||
* series of bytes from a device on the bus
|
|
||||||
* Input address: 7bit i2c device address
|
|
||||||
* data: pointer to byte array
|
|
||||||
* length: number of bytes to read into array
|
|
||||||
* Output number of bytes read
|
|
||||||
*/
|
|
||||||
uint8_t twi_readFrom(uint8_t address, uint8_t* data, uint8_t length)
|
|
||||||
{
|
|
||||||
uint8_t i;
|
|
||||||
|
|
||||||
// ensure data will fit into buffer
|
|
||||||
if(TWI_BUFFER_LENGTH < length){
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
// wait until twi is ready, become master receiver
|
|
||||||
while(TWI_READY != twi_state){
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
twi_state = TWI_MRX;
|
|
||||||
// reset error state (0xFF.. no error occured)
|
|
||||||
twi_error = 0xFF;
|
|
||||||
|
|
||||||
// initialize buffer iteration vars
|
|
||||||
twi_masterBufferIndex = 0;
|
|
||||||
twi_masterBufferLength = length-1; // This is not intuitive, read on...
|
|
||||||
// On receive, the previously configured ACK/NACK setting is transmitted in
|
|
||||||
// response to the received byte before the interrupt is signalled.
|
|
||||||
// Therefor we must actually set NACK when the _next_ to last byte is
|
|
||||||
// received, causing that NACK to be sent in response to receiving the last
|
|
||||||
// expected byte of data.
|
|
||||||
|
|
||||||
// build sla+w, slave device address + w bit
|
|
||||||
twi_slarw = TW_READ;
|
|
||||||
twi_slarw |= address << 1;
|
|
||||||
|
|
||||||
// send start condition
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTA);
|
|
||||||
|
|
||||||
// wait for read operation to complete
|
|
||||||
while(TWI_MRX == twi_state){
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (twi_masterBufferIndex < length)
|
|
||||||
length = twi_masterBufferIndex;
|
|
||||||
|
|
||||||
// copy twi buffer to data
|
|
||||||
for(i = 0; i < length; ++i){
|
|
||||||
data[i] = twi_masterBuffer[i];
|
|
||||||
}
|
|
||||||
|
|
||||||
return length;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_writeTo
|
|
||||||
* Desc attempts to become twi bus master and write a
|
|
||||||
* series of bytes to a device on the bus
|
|
||||||
* Input address: 7bit i2c device address
|
|
||||||
* data: pointer to byte array
|
|
||||||
* length: number of bytes in array
|
|
||||||
* wait: boolean indicating to wait for write or not
|
|
||||||
* Output 0 .. success
|
|
||||||
* 1 .. length to long for buffer
|
|
||||||
* 2 .. address send, NACK received
|
|
||||||
* 3 .. data send, NACK received
|
|
||||||
* 4 .. other twi error (lost bus arbitration, bus error, ..)
|
|
||||||
*/
|
|
||||||
uint8_t twi_writeTo(uint8_t address, uint8_t* data, uint8_t length, uint8_t wait)
|
|
||||||
{
|
|
||||||
uint8_t i;
|
|
||||||
|
|
||||||
// ensure data will fit into buffer
|
|
||||||
if(TWI_BUFFER_LENGTH < length){
|
|
||||||
return 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
// wait until twi is ready, become master transmitter
|
|
||||||
while(TWI_READY != twi_state){
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
twi_state = TWI_MTX;
|
|
||||||
// reset error state (0xFF.. no error occured)
|
|
||||||
twi_error = 0xFF;
|
|
||||||
|
|
||||||
// initialize buffer iteration vars
|
|
||||||
twi_masterBufferIndex = 0;
|
|
||||||
twi_masterBufferLength = length;
|
|
||||||
|
|
||||||
// copy data to twi buffer
|
|
||||||
for(i = 0; i < length; ++i){
|
|
||||||
twi_masterBuffer[i] = data[i];
|
|
||||||
}
|
|
||||||
|
|
||||||
// build sla+w, slave device address + w bit
|
|
||||||
twi_slarw = TW_WRITE;
|
|
||||||
twi_slarw |= address << 1;
|
|
||||||
|
|
||||||
// send start condition
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTA);
|
|
||||||
|
|
||||||
// wait for write operation to complete
|
|
||||||
while(wait && (TWI_MTX == twi_state)){
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (twi_error == 0xFF)
|
|
||||||
return 0; // success
|
|
||||||
else if (twi_error == TW_MT_SLA_NACK)
|
|
||||||
return 2; // error: address send, nack received
|
|
||||||
else if (twi_error == TW_MT_DATA_NACK)
|
|
||||||
return 3; // error: data send, nack received
|
|
||||||
else
|
|
||||||
return 4; // other twi error
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_transmit
|
|
||||||
* Desc fills slave tx buffer with data
|
|
||||||
* must be called in slave tx event callback
|
|
||||||
* Input data: pointer to byte array
|
|
||||||
* length: number of bytes in array
|
|
||||||
* Output 1 length too long for buffer
|
|
||||||
* 2 not slave transmitter
|
|
||||||
* 0 ok
|
|
||||||
*/
|
|
||||||
uint8_t twi_transmit(uint8_t* data, uint8_t length)
|
|
||||||
{
|
|
||||||
uint8_t i;
|
|
||||||
|
|
||||||
// ensure data will fit into buffer
|
|
||||||
if(TWI_BUFFER_LENGTH < length){
|
|
||||||
return 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
// ensure we are currently a slave transmitter
|
|
||||||
if(TWI_STX != twi_state){
|
|
||||||
return 2;
|
|
||||||
}
|
|
||||||
|
|
||||||
// set length and copy data into tx buffer
|
|
||||||
twi_txBufferLength = length;
|
|
||||||
for(i = 0; i < length; ++i){
|
|
||||||
twi_txBuffer[i] = data[i];
|
|
||||||
}
|
|
||||||
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_attachSlaveRxEvent
|
|
||||||
* Desc sets function called before a slave read operation
|
|
||||||
* Input function: callback function to use
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_attachSlaveRxEvent( void (*function)(uint8_t*, int) )
|
|
||||||
{
|
|
||||||
twi_onSlaveReceive = function;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_attachSlaveTxEvent
|
|
||||||
* Desc sets function called before a slave write operation
|
|
||||||
* Input function: callback function to use
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_attachSlaveTxEvent( void (*function)(void) )
|
|
||||||
{
|
|
||||||
twi_onSlaveTransmit = function;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_reply
|
|
||||||
* Desc sends byte or readys receive line
|
|
||||||
* Input ack: byte indicating to ack or to nack
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_reply(uint8_t ack)
|
|
||||||
{
|
|
||||||
// transmit master read ready signal, with or without ack
|
|
||||||
if(ack){
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA);
|
|
||||||
}else{
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_stop
|
|
||||||
* Desc relinquishes bus master status
|
|
||||||
* Input none
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_stop(void)
|
|
||||||
{
|
|
||||||
// send stop condition
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
|
|
||||||
|
|
||||||
// wait for stop condition to be exectued on bus
|
|
||||||
// TWINT is not set after a stop condition!
|
|
||||||
while(TWCR & _BV(TWSTO)){
|
|
||||||
continue;
|
|
||||||
}
|
|
||||||
|
|
||||||
// update twi state
|
|
||||||
twi_state = TWI_READY;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Function twi_releaseBus
|
|
||||||
* Desc releases bus control
|
|
||||||
* Input none
|
|
||||||
* Output none
|
|
||||||
*/
|
|
||||||
void twi_releaseBus(void)
|
|
||||||
{
|
|
||||||
// release bus
|
|
||||||
TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT);
|
|
||||||
|
|
||||||
// update twi state
|
|
||||||
twi_state = TWI_READY;
|
|
||||||
}
|
|
||||||
|
|
||||||
SIGNAL(TWI_vect)
|
|
||||||
{
|
|
||||||
switch(TW_STATUS){
|
|
||||||
// All Master
|
|
||||||
case TW_START: // sent start condition
|
|
||||||
case TW_REP_START: // sent repeated start condition
|
|
||||||
// copy device address and r/w bit to output register and ack
|
|
||||||
TWDR = twi_slarw;
|
|
||||||
twi_reply(1);
|
|
||||||
break;
|
|
||||||
|
|
||||||
// Master Transmitter
|
|
||||||
case TW_MT_SLA_ACK: // slave receiver acked address
|
|
||||||
case TW_MT_DATA_ACK: // slave receiver acked data
|
|
||||||
// if there is data to send, send it, otherwise stop
|
|
||||||
if(twi_masterBufferIndex < twi_masterBufferLength){
|
|
||||||
// copy data to output register and ack
|
|
||||||
TWDR = twi_masterBuffer[twi_masterBufferIndex++];
|
|
||||||
twi_reply(1);
|
|
||||||
}else{
|
|
||||||
twi_stop();
|
|
||||||
}
|
|
||||||
break;
|
|
||||||
case TW_MT_SLA_NACK: // address sent, nack received
|
|
||||||
twi_error = TW_MT_SLA_NACK;
|
|
||||||
twi_stop();
|
|
||||||
break;
|
|
||||||
case TW_MT_DATA_NACK: // data sent, nack received
|
|
||||||
twi_error = TW_MT_DATA_NACK;
|
|
||||||
twi_stop();
|
|
||||||
break;
|
|
||||||
case TW_MT_ARB_LOST: // lost bus arbitration
|
|
||||||
twi_error = TW_MT_ARB_LOST;
|
|
||||||
twi_releaseBus();
|
|
||||||
break;
|
|
||||||
|
|
||||||
// Master Receiver
|
|
||||||
case TW_MR_DATA_ACK: // data received, ack sent
|
|
||||||
// put byte into buffer
|
|
||||||
twi_masterBuffer[twi_masterBufferIndex++] = TWDR;
|
|
||||||
[[fallthrough]];
|
|
||||||
case TW_MR_SLA_ACK: // address sent, ack received
|
|
||||||
// ack if more bytes are expected, otherwise nack
|
|
||||||
if(twi_masterBufferIndex < twi_masterBufferLength){
|
|
||||||
twi_reply(1);
|
|
||||||
}else{
|
|
||||||
twi_reply(0);
|
|
||||||
}
|
|
||||||
break;
|
|
||||||
case TW_MR_DATA_NACK: // data received, nack sent
|
|
||||||
// put final byte into buffer
|
|
||||||
twi_masterBuffer[twi_masterBufferIndex++] = TWDR;
|
|
||||||
[[fallthrough]];
|
|
||||||
case TW_MR_SLA_NACK: // address sent, nack received
|
|
||||||
twi_stop();
|
|
||||||
break;
|
|
||||||
// TW_MR_ARB_LOST handled by TW_MT_ARB_LOST case
|
|
||||||
|
|
||||||
// Slave Receiver
|
|
||||||
case TW_SR_SLA_ACK: // addressed, returned ack
|
|
||||||
case TW_SR_GCALL_ACK: // addressed generally, returned ack
|
|
||||||
case TW_SR_ARB_LOST_SLA_ACK: // lost arbitration, returned ack
|
|
||||||
case TW_SR_ARB_LOST_GCALL_ACK: // lost arbitration, returned ack
|
|
||||||
// enter slave receiver mode
|
|
||||||
twi_state = TWI_SRX;
|
|
||||||
// indicate that rx buffer can be overwritten and ack
|
|
||||||
twi_rxBufferIndex = 0;
|
|
||||||
twi_reply(1);
|
|
||||||
break;
|
|
||||||
case TW_SR_DATA_ACK: // data received, returned ack
|
|
||||||
case TW_SR_GCALL_DATA_ACK: // data received generally, returned ack
|
|
||||||
// if there is still room in the rx buffer
|
|
||||||
if(twi_rxBufferIndex < TWI_BUFFER_LENGTH){
|
|
||||||
// put byte in buffer and ack
|
|
||||||
twi_rxBuffer[twi_rxBufferIndex++] = TWDR;
|
|
||||||
twi_reply(1);
|
|
||||||
}else{
|
|
||||||
// otherwise nack
|
|
||||||
twi_reply(0);
|
|
||||||
}
|
|
||||||
break;
|
|
||||||
case TW_SR_STOP: // stop or repeated start condition received
|
|
||||||
// put a null char after data if there's room
|
|
||||||
if(twi_rxBufferIndex < TWI_BUFFER_LENGTH){
|
|
||||||
twi_rxBuffer[twi_rxBufferIndex] = '\0';
|
|
||||||
}
|
|
||||||
// sends ack and stops interface for clock stretching
|
|
||||||
twi_stop();
|
|
||||||
// callback to user defined callback
|
|
||||||
twi_onSlaveReceive(twi_rxBuffer, twi_rxBufferIndex);
|
|
||||||
// since we submit rx buffer to "wire" library, we can reset it
|
|
||||||
twi_rxBufferIndex = 0;
|
|
||||||
// ack future responses and leave slave receiver state
|
|
||||||
twi_releaseBus();
|
|
||||||
break;
|
|
||||||
case TW_SR_DATA_NACK: // data received, returned nack
|
|
||||||
case TW_SR_GCALL_DATA_NACK: // data received generally, returned nack
|
|
||||||
// nack back at master
|
|
||||||
twi_reply(0);
|
|
||||||
break;
|
|
||||||
|
|
||||||
// Slave Transmitter
|
|
||||||
case TW_ST_SLA_ACK: // addressed, returned ack
|
|
||||||
case TW_ST_ARB_LOST_SLA_ACK: // arbitration lost, returned ack
|
|
||||||
// enter slave transmitter mode
|
|
||||||
twi_state = TWI_STX;
|
|
||||||
// ready the tx buffer index for iteration
|
|
||||||
twi_txBufferIndex = 0;
|
|
||||||
// set tx buffer length to be zero, to verify if user changes it
|
|
||||||
twi_txBufferLength = 0;
|
|
||||||
// request for txBuffer to be filled and length to be set
|
|
||||||
// note: user must call twi_transmit(bytes, length) to do this
|
|
||||||
twi_onSlaveTransmit();
|
|
||||||
// if they didn't change buffer & length, initialize it
|
|
||||||
if(0 == twi_txBufferLength){
|
|
||||||
twi_txBufferLength = 1;
|
|
||||||
twi_txBuffer[0] = 0x00;
|
|
||||||
}
|
|
||||||
// transmit first byte from buffer, fall
|
|
||||||
[[fallthrough]];
|
|
||||||
case TW_ST_DATA_ACK: // byte sent, ack returned
|
|
||||||
// copy data to output register
|
|
||||||
TWDR = twi_txBuffer[twi_txBufferIndex++];
|
|
||||||
// if there is more to send, ack, otherwise nack
|
|
||||||
if(twi_txBufferIndex < twi_txBufferLength){
|
|
||||||
twi_reply(1);
|
|
||||||
}else{
|
|
||||||
twi_reply(0);
|
|
||||||
}
|
|
||||||
break;
|
|
||||||
case TW_ST_DATA_NACK: // received nack, we are done
|
|
||||||
case TW_ST_LAST_DATA: // received ack, but we are done already!
|
|
||||||
// ack future responses
|
|
||||||
twi_reply(1);
|
|
||||||
// leave slave receiver state
|
|
||||||
twi_state = TWI_READY;
|
|
||||||
break;
|
|
||||||
|
|
||||||
// All
|
|
||||||
case TW_NO_INFO: // no state information
|
|
||||||
break;
|
|
||||||
case TW_BUS_ERROR: // bus error, illegal stop/start
|
|
||||||
twi_error = TW_BUS_ERROR;
|
|
||||||
twi_stop();
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
@ -1,55 +0,0 @@
|
|||||||
/*
|
|
||||||
twi.h - TWI/I2C library for Wiring & Arduino
|
|
||||||
Copyright (c) 2006 Nicholas Zambetti. All right reserved.
|
|
||||||
|
|
||||||
This library is free software; you can redistribute it and/or
|
|
||||||
modify it under the terms of the GNU Lesser General Public
|
|
||||||
License as published by the Free Software Foundation; either
|
|
||||||
version 2.1 of the License, or (at your option) any later version.
|
|
||||||
|
|
||||||
This library is distributed in the hope that it will be useful,
|
|
||||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
||||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
||||||
Lesser General Public License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU Lesser General Public
|
|
||||||
License along with this library; if not, write to the Free Software
|
|
||||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
||||||
*/
|
|
||||||
|
|
||||||
#ifndef twi_h
|
|
||||||
#define twi_h
|
|
||||||
|
|
||||||
#include <inttypes.h>
|
|
||||||
|
|
||||||
#include "../clock.hpp"
|
|
||||||
|
|
||||||
//#define ATMEGA8
|
|
||||||
|
|
||||||
#ifndef TWI_FREQ
|
|
||||||
#define TWI_FREQ 100000L
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#ifndef TWI_BUFFER_LENGTH
|
|
||||||
#define TWI_BUFFER_LENGTH 32
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#define TWI_READY 0
|
|
||||||
#define TWI_MRX 1
|
|
||||||
#define TWI_MTX 2
|
|
||||||
#define TWI_SRX 3
|
|
||||||
#define TWI_STX 4
|
|
||||||
|
|
||||||
void twi_init(void);
|
|
||||||
void twi_setAddress(uint8_t);
|
|
||||||
uint8_t twi_readFrom(uint8_t, uint8_t*, uint8_t);
|
|
||||||
uint8_t twi_writeTo(uint8_t, uint8_t*, uint8_t, uint8_t);
|
|
||||||
uint8_t twi_transmit(uint8_t*, uint8_t);
|
|
||||||
void twi_attachSlaveRxEvent( void (*)(uint8_t*, int) );
|
|
||||||
void twi_attachSlaveTxEvent( void (*)(void) );
|
|
||||||
void twi_reply(uint8_t);
|
|
||||||
void twi_stop(void);
|
|
||||||
void twi_releaseBus(void);
|
|
||||||
|
|
||||||
#endif
|
|
||||||
|
|
||||||
226
twi.cpp
226
twi.cpp
@ -1,226 +0,0 @@
|
|||||||
/*
|
|
||||||
TwoWire.cpp - TWI/I2C library for Wiring & Arduino
|
|
||||||
Copyright (c) 2006 Nicholas Zambetti. All right reserved.
|
|
||||||
|
|
||||||
This library is free software; you can redistribute it and/or
|
|
||||||
modify it under the terms of the GNU Lesser General Public
|
|
||||||
License as published by the Free Software Foundation; either
|
|
||||||
version 2.1 of the License, or (at your option) any later version.
|
|
||||||
|
|
||||||
This library is distributed in the hope that it will be useful,
|
|
||||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
||||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
||||||
Lesser General Public License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU Lesser General Public
|
|
||||||
License along with this library; if not, write to the Free Software
|
|
||||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
||||||
*/
|
|
||||||
|
|
||||||
#include <stdlib.h>
|
|
||||||
#include <string.h>
|
|
||||||
#include <inttypes.h>
|
|
||||||
#include "twi-lowlevel.h"
|
|
||||||
|
|
||||||
#include "twi.h"
|
|
||||||
|
|
||||||
// local variables
|
|
||||||
uint8_t rxBuffer[BUFFER_LENGTH];
|
|
||||||
uint8_t rxBufferIndex = 0;
|
|
||||||
uint8_t rxBufferLength = 0;
|
|
||||||
|
|
||||||
uint8_t txAddress = 0;
|
|
||||||
uint8_t txBuffer[BUFFER_LENGTH];
|
|
||||||
uint8_t txBufferIndex = 0;
|
|
||||||
uint8_t txBufferLength = 0;
|
|
||||||
|
|
||||||
uint8_t transmitting = 0;
|
|
||||||
void (*user_onRequest)(void);
|
|
||||||
void (*user_onReceive)(int);
|
|
||||||
|
|
||||||
void onRequestService(void);
|
|
||||||
void onReceiveService(uint8_t*, int);
|
|
||||||
|
|
||||||
void twi_init_master(void)
|
|
||||||
{
|
|
||||||
rxBufferIndex = 0;
|
|
||||||
rxBufferLength = 0;
|
|
||||||
|
|
||||||
txBufferIndex = 0;
|
|
||||||
txBufferLength = 0;
|
|
||||||
|
|
||||||
twi_init();
|
|
||||||
}
|
|
||||||
|
|
||||||
void twi_init_slave(uint8_t address)
|
|
||||||
{
|
|
||||||
twi_setAddress(address);
|
|
||||||
twi_attachSlaveTxEvent(onRequestService);
|
|
||||||
twi_attachSlaveRxEvent(onReceiveService);
|
|
||||||
twi_init_master();
|
|
||||||
}
|
|
||||||
|
|
||||||
uint8_t twi_request_from(uint8_t address, uint8_t quantity)
|
|
||||||
{
|
|
||||||
// clamp to buffer length
|
|
||||||
if(quantity > BUFFER_LENGTH){
|
|
||||||
quantity = BUFFER_LENGTH;
|
|
||||||
}
|
|
||||||
// perform blocking read into buffer
|
|
||||||
uint8_t read = twi_readFrom(address, rxBuffer, quantity);
|
|
||||||
// set rx buffer iterator vars
|
|
||||||
rxBufferIndex = 0;
|
|
||||||
rxBufferLength = read;
|
|
||||||
|
|
||||||
return read;
|
|
||||||
}
|
|
||||||
|
|
||||||
void twi_begin_transmission(uint8_t address)
|
|
||||||
{
|
|
||||||
// indicate that we are transmitting
|
|
||||||
transmitting = 1;
|
|
||||||
// set address of targeted slave
|
|
||||||
txAddress = address;
|
|
||||||
// reset tx buffer iterator vars
|
|
||||||
txBufferIndex = 0;
|
|
||||||
txBufferLength = 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
uint8_t twi_end_transmission(void)
|
|
||||||
{
|
|
||||||
// transmit buffer (blocking)
|
|
||||||
int8_t ret = twi_writeTo(txAddress, txBuffer, txBufferLength, 1);
|
|
||||||
// reset tx buffer iterator vars
|
|
||||||
txBufferIndex = 0;
|
|
||||||
txBufferLength = 0;
|
|
||||||
// indicate that we are done transmitting
|
|
||||||
transmitting = 0;
|
|
||||||
return ret;
|
|
||||||
}
|
|
||||||
|
|
||||||
// must be called in:
|
|
||||||
// slave tx event callback
|
|
||||||
// or after beginTransmission(address)
|
|
||||||
void twi_send_byte(uint8_t data)
|
|
||||||
{
|
|
||||||
if(transmitting){
|
|
||||||
// in master transmitter mode
|
|
||||||
// don't bother if buffer is full
|
|
||||||
if(txBufferLength >= BUFFER_LENGTH){
|
|
||||||
return;
|
|
||||||
}
|
|
||||||
// put byte in tx buffer
|
|
||||||
txBuffer[txBufferIndex] = data;
|
|
||||||
++txBufferIndex;
|
|
||||||
// update amount in buffer
|
|
||||||
txBufferLength = txBufferIndex;
|
|
||||||
}else{
|
|
||||||
// in slave send mode
|
|
||||||
// reply to master
|
|
||||||
twi_transmit(&data, 1);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
// must be called in:
|
|
||||||
// slave tx event callback
|
|
||||||
// or after beginTransmission(address)
|
|
||||||
void twi_send(uint8_t* data, uint8_t quantity)
|
|
||||||
{
|
|
||||||
if(transmitting){
|
|
||||||
// in master transmitter mode
|
|
||||||
for(uint8_t i = 0; i < quantity; ++i){
|
|
||||||
twi_send_byte(data[i]);
|
|
||||||
}
|
|
||||||
}else{
|
|
||||||
// in slave send mode
|
|
||||||
// reply to master
|
|
||||||
twi_transmit(data, quantity);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
// must be called in:
|
|
||||||
// slave tx event callback
|
|
||||||
// or after beginTransmission(address)
|
|
||||||
void twi_send_char(char* data)
|
|
||||||
{
|
|
||||||
twi_send((uint8_t*)data, strlen(data));
|
|
||||||
}
|
|
||||||
|
|
||||||
// must be called in:
|
|
||||||
// slave rx event callback
|
|
||||||
// or after requestFrom(address, numBytes)
|
|
||||||
uint8_t twi_available(void)
|
|
||||||
{
|
|
||||||
return rxBufferLength - rxBufferIndex;
|
|
||||||
}
|
|
||||||
|
|
||||||
// must be called in:
|
|
||||||
// slave rx event callback
|
|
||||||
// or after requestFrom(address, numBytes)
|
|
||||||
uint8_t twi_receive(void)
|
|
||||||
{
|
|
||||||
// default to returning null char
|
|
||||||
// for people using with char strings
|
|
||||||
uint8_t value = '\0';
|
|
||||||
|
|
||||||
// get each successive byte on each call
|
|
||||||
if(rxBufferIndex < rxBufferLength){
|
|
||||||
value = rxBuffer[rxBufferIndex];
|
|
||||||
++rxBufferIndex;
|
|
||||||
}
|
|
||||||
|
|
||||||
return value;
|
|
||||||
}
|
|
||||||
|
|
||||||
// behind the scenes function that is called when data is received
|
|
||||||
void onReceiveService(uint8_t* inBytes, int numBytes)
|
|
||||||
{
|
|
||||||
// don't bother if user hasn't registered a callback
|
|
||||||
if(!user_onReceive){
|
|
||||||
return;
|
|
||||||
}
|
|
||||||
// don't bother if rx buffer is in use by a master requestFrom() op
|
|
||||||
// i know this drops data, but it allows for slight stupidity
|
|
||||||
// meaning, they may not have read all the master requestFrom() data yet
|
|
||||||
if(rxBufferIndex < rxBufferLength){
|
|
||||||
return;
|
|
||||||
}
|
|
||||||
// copy twi rx buffer into local read buffer
|
|
||||||
// this enables new reads to happen in parallel
|
|
||||||
for(uint8_t i = 0; i < numBytes; ++i){
|
|
||||||
rxBuffer[i] = inBytes[i];
|
|
||||||
}
|
|
||||||
// set rx iterator vars
|
|
||||||
rxBufferIndex = 0;
|
|
||||||
rxBufferLength = numBytes;
|
|
||||||
// alert user program
|
|
||||||
user_onReceive(numBytes);
|
|
||||||
}
|
|
||||||
|
|
||||||
// behind the scenes function that is called when data is requested
|
|
||||||
void onRequestService(void)
|
|
||||||
{
|
|
||||||
// don't bother if user hasn't registered a callback
|
|
||||||
if(!user_onRequest){
|
|
||||||
return;
|
|
||||||
}
|
|
||||||
// reset tx buffer iterator vars
|
|
||||||
// !!! this will kill any pending pre-master sendTo() activity
|
|
||||||
txBufferIndex = 0;
|
|
||||||
txBufferLength = 0;
|
|
||||||
// alert user program
|
|
||||||
user_onRequest();
|
|
||||||
}
|
|
||||||
|
|
||||||
// sets function called on slave write
|
|
||||||
void twi_set_on_receive( void (*function)(int) )
|
|
||||||
{
|
|
||||||
user_onReceive = function;
|
|
||||||
}
|
|
||||||
|
|
||||||
// sets function called on slave read
|
|
||||||
void twi_set_on_request( void (*function)(void) )
|
|
||||||
{
|
|
||||||
user_onRequest = function;
|
|
||||||
}
|
|
||||||
|
|
||||||
40
twi.h
40
twi.h
@ -1,40 +0,0 @@
|
|||||||
/*
|
|
||||||
TwoWire.h - TWI/I2C library for Arduino & Wiring
|
|
||||||
Copyright (c) 2006 Nicholas Zambetti. All right reserved.
|
|
||||||
|
|
||||||
This library is free software; you can redistribute it and/or
|
|
||||||
modify it under the terms of the GNU Lesser General Public
|
|
||||||
License as published by the Free Software Foundation; either
|
|
||||||
version 2.1 of the License, or (at your option) any later version.
|
|
||||||
|
|
||||||
This library is distributed in the hope that it will be useful,
|
|
||||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
||||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
||||||
Lesser General Public License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU Lesser General Public
|
|
||||||
License along with this library; if not, write to the Free Software
|
|
||||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
||||||
*/
|
|
||||||
|
|
||||||
#ifndef TwoWire_h
|
|
||||||
#define TwoWire_h
|
|
||||||
|
|
||||||
#include <inttypes.h>
|
|
||||||
|
|
||||||
#define BUFFER_LENGTH 32
|
|
||||||
|
|
||||||
void twi_init_master(void);
|
|
||||||
void twi_init_slave(uint8_t);
|
|
||||||
void twi_begin_transmission(uint8_t);
|
|
||||||
uint8_t twi_end_transmission(void);
|
|
||||||
uint8_t twi_request_from(uint8_t, uint8_t);
|
|
||||||
void twi_send_byte(uint8_t);
|
|
||||||
void twi_send(uint8_t*, uint8_t);
|
|
||||||
void twi_send_char(char*);
|
|
||||||
uint8_t twi_available(void);
|
|
||||||
uint8_t twi_receive(void);
|
|
||||||
void twi_set_on_receive( void (*)(int) );
|
|
||||||
void twi_set_on_request( void (*)(void) );
|
|
||||||
|
|
||||||
#endif
|
|
||||||
Loading…
Reference in New Issue
Block a user