24 Commits

Author SHA1 Message Date
2147637385 Update submodule 2020-05-17 20:11:51 +02:00
966af1d5cf Add ability to read alarm times 2020-05-17 20:07:13 +02:00
a83671bda5 Add alarms to example 2020-05-17 19:56:11 +02:00
7e8a6b0dad Add power control for RTC 2020-05-17 15:40:29 +02:00
a897b7d9be Move comparison operator into library 2020-05-17 15:40:15 +02:00
f8ee536829 Only pass i2c backend to rtc class 2020-05-16 19:52:49 +02:00
2fd64c8611 Implement setting time through serial 2020-05-16 19:48:37 +02:00
97bb522189 Remove old rtc lib and systime 2020-05-16 19:20:32 +02:00
b8c7c9ec5c Adapt to moved type submodule 2020-05-16 17:44:16 +02:00
5d77cad8d7 Add setting date-time example with new rtc lib 2020-05-16 17:26:56 +02:00
4b3dd99ebc Add usage for new C++ driver 2020-05-15 19:48:22 +02:00
f00a154e59 Change i2c library 2020-05-15 11:51:51 +02:00
e9d3a95239 Move C time API glue from driver to user space 2020-05-15 10:21:34 +02:00
b2065b987a Switch from old usart to new uart library 2020-05-15 09:43:06 +02:00
85e37de950 Ran clang-format 2020-05-15 09:29:26 +02:00
7310eb2c9a Remove bootloader support 2020-05-15 09:28:05 +02:00
b02454c45b Update submodule 2020-05-15 09:26:08 +02:00
af4f2ed0e5 Update project file to C++17 config with gcc 9 2020-05-15 09:24:24 +02:00
7a8d31718f Add gitignore and clang-format file 2020-05-15 09:21:08 +02:00
05e8b1b53f Change to 16 MHz crystal 2020-05-15 09:14:31 +02:00
a340cb04d3 Actually use ds3231 submodule instead of duplicating code 2020-05-15 09:06:34 +02:00
4cffd8f56b Fix submodule path 2020-05-15 09:01:11 +02:00
6072c34eef Fixed setting time bug, because of uninitialized tm struct 2018-01-02 17:21:04 +01:00
4bc59d1a33 Changed wrong CPU FREQ define to central correct one 2017-12-17 10:53:38 +01:00
29 changed files with 535 additions and 1028 deletions

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@@ -1,15 +1,13 @@
---
BasedOnStyle: LLVM
Standard: Latest
ColumnLimit: 120
IndentWidth: 4
TabWidth: 4
UseTab: ForIndentation
AlignEscapedNewlines: DontAlign
AllowShortFunctionsOnASingleLine: Empty
BreakTemplateDeclarations: Yes
AlwaysBreakTemplateDeclarations: true
BreakBeforeBraces: Custom
BraceWrapping:
AfterFunction: true
InsertBraces: true
...

32
.clangd
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@@ -1,32 +0,0 @@
# Editor accommodations for the second frontend. No compilation database is
# named here: this driver is made to be vendored, and this file travels with
# it — a consumer's own database then covers these headers, at the consumer's
# chip. The checkout that is opened as a folder names its build tree in
# .vscode/settings.json instead.
CompileFlags:
Add:
# clang has no 24-bit integer and GCC's are keywords, not macros, so the
# editor needs a stand-in for avr::uint24_t. The next width up is the only
# one available — clang rejects _BitInt(24) on this target.
- -D__uint24=unsigned long
- -D__int24=long
# clangd forwards the driver's system includes but not its own header
# directory, so <stdint.h> resolves to avr-libc's, which still gates the
# limit and constant macros on the C++98 opt-in.
- -D__STDC_LIMIT_MACROS
- -D__STDC_CONSTANT_MACROS
# isr::emit spells a vector number into [[gnu::signal(N)]], which clang
# rejects rather than ignores — enough of them in one TU to reach the
# default limit of 19 inside the headers and truncate the parse.
- -ferror-limit=0
Remove:
# The build promotes warnings for the compiler that has to be right about
# them; in the editor the flag paints a second frontend's opinions in the
# colour reserved for things that do not compile.
- -Werror
Diagnostics:
Suppress:
# clang's AVR `signal` attribute takes no arguments and it knows none of
# progmem, naked or OS_main. A misspelling is what the build is for.
- attribute_wrong_number_arguments
- unknown-attributes

20
.gitignore vendored
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@@ -1,9 +1,11 @@
build/
.cache/
# Atmel Studio: generated per machine, its build outputs, and per-user state
ide/*/*.componentinfo.xml
ide/*/Debug/
ide/*/Release/
ide/.vs/
ide/*.log
.vs
Release
Debug
*.componentinfo.xml
*.elf
*.o
*.hex
*.srec
*.eeprom
*.lss
*.map

21
.gitmodules vendored
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@@ -1,3 +1,18 @@
[submodule "libavr"]
path = libavr
url = ../libavr.git
[submodule "ds3231/ds3231"]
path = ds3231/ds3231
url = git@git.blackmark.me:avr/ds3231.git
[submodule "ds3231/uart"]
path = ds3231/uart
url = git@git.blackmark.me:avr/uart.git
[submodule "ds3231/io"]
path = ds3231/io
url = git@git.blackmark.me:avr/io.git
[submodule "ds3231/flash"]
path = ds3231/flash
url = git@git.blackmark.me:avr/flash.git
[submodule "ds3231/i2c"]
path = ds3231/i2c
url = git@git.blackmark.me:avr/i2c.git
[submodule "ds3231/util"]
path = ds3231/util
url = git@git.blackmark.me:avr/util.git

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@@ -1,6 +0,0 @@
{
"recommendations": [
"llvm-vs-code-extensions.vscode-clangd",
"ms-vscode.cmake-tools"
]
}

37
.vscode/settings.json vendored
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@@ -1,37 +0,0 @@
{
// clangd is the language server; the cpptools engine would parse every file
// a second time and disagree, since nothing tells it about a cross
// compiler.
"C_Cpp.intelliSenseEngine": "disabled",
// --query-driver lets clangd ask the cross compiler for its own system
// includes and target. The database is named here rather than in .clangd
// because that file travels with the driver into a consumer's submodule,
// where a build tree of this repo's own need not exist.
"clangd.arguments": [
"--compile-commands-dir=${workspaceFolder}/build/atmega328p-generated",
"--query-driver=**avr-g++*",
"--header-insertion=never"
],
// The presets are the build interface; the toolchain file inside the
// libavr submodule is the one place the compiler is chosen. The submodule
// carries no local/toolchain for it to discover, so the prefix is named
// here, for the window that opens this folder.
"cmake.useCMakePresets": "always",
"cmake.environment": {
"LIBAVR_TOOLCHAIN": "D:/dev/libavr/local/toolchain/avr-gcc-16.1.0-mingw"
},
"cmake.configureOnOpen": true,
"cmake.options.statusBarVisibility": "compact",
"files.watcherExclude": {
"**/build/**": true,
"**/libavr/**": true
},
"files.associations": {
".clangd": "yaml",
".clang-format": "yaml"
}
}

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@@ -1,29 +0,0 @@
cmake_minimum_required(VERSION 3.28)
project(ds3231 LANGUAGES CXX)
# libavr rides as the pinned submodule; LIBAVR_ROOT (cache or environment)
# overrides it for tandem development against a working tree. The toolchain
# file comes from the submodule via CMakePresets.json either way.
if(NOT LIBAVR_ROOT AND DEFINED ENV{LIBAVR_ROOT})
set(LIBAVR_ROOT $ENV{LIBAVR_ROOT})
endif()
if(NOT LIBAVR_ROOT)
set(LIBAVR_ROOT ${CMAKE_CURRENT_SOURCE_DIR}/libavr)
endif()
if(NOT EXISTS ${LIBAVR_ROOT}/CMakeLists.txt)
message(FATAL_ERROR "libavr not found at ${LIBAVR_ROOT} - run: git submodule update --init libavr")
endif()
add_subdirectory(${LIBAVR_ROOT} libavr-build)
add_library(ds3231 INTERFACE)
target_include_directories(ds3231 INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/include)
target_link_libraries(ds3231 INTERFACE libavr)
include(${LIBAVR_ROOT}/cmake/checks.cmake)
if(PROJECT_IS_TOP_LEVEL)
add_subdirectory(example)
enable_testing()
add_subdirectory(test)
endif()

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@@ -1,43 +0,0 @@
{
"version": 8,
"configurePresets": [
{
"name": "base",
"hidden": true,
"generator": "Ninja",
"binaryDir": "${sourceDir}/build/${presetName}",
"toolchainFile": "${sourceDir}/libavr/cmake/avr-toolchain.cmake",
"cacheVariables": {
"CMAKE_BUILD_TYPE": "Release",
"CMAKE_EXPORT_COMPILE_COMMANDS": "ON",
"CMAKE_COLOR_DIAGNOSTICS": "ON"
}
},
{
"name": "attiny85-generated",
"inherits": "base",
"cacheVariables": { "LIBAVR_MCU": "attiny85", "LIBAVR_REFLECT": "OFF" }
},
{
"name": "attiny85-reflect",
"inherits": "base",
"cacheVariables": { "LIBAVR_MCU": "attiny85", "LIBAVR_REFLECT": "ON" }
},
{
"name": "atmega328p-generated",
"inherits": "base",
"cacheVariables": { "LIBAVR_MCU": "atmega328p", "LIBAVR_REFLECT": "OFF" }
},
{
"name": "atmega328p-reflect",
"inherits": "base",
"cacheVariables": { "LIBAVR_MCU": "atmega328p", "LIBAVR_REFLECT": "ON" }
}
],
"buildPresets": [
{ "name": "attiny85-generated", "configurePreset": "attiny85-generated" },
{ "name": "attiny85-reflect", "configurePreset": "attiny85-reflect" },
{ "name": "atmega328p-generated", "configurePreset": "atmega328p-generated" },
{ "name": "atmega328p-reflect", "configurePreset": "atmega328p-reflect" }
]
}

21
LICENSE
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@@ -1,21 +0,0 @@
MIT License
Copyright (c) 2020 BlackMark
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is furnished
to do so, subject to the following conditions:
The above copyright notice and this permission notice (including the next
paragraph) shall be included in all copies or substantial portions of the
Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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@@ -1,94 +0,0 @@
# ds3231
Maxim DS3231 RTC driver on [libavr](https://git.blackmark.me/avr/libavr):
clock and alarm read/write, alarm interrupts, oscillator-stop detection,
die temperature. One source runs on every libavr chip — TWI hardware on
the mega328P, open-drain software I2C on the tinies. All bus errors
surface as `std::expected`.
```cpp
using bus = dev::i2c<{.frequency = 100_kHz}>;
using rtc = ds3231::device<bus>;
auto now = rtc::read_clock(); // result<date_time>
auto armed = rtc::set_alarm1({}, ds3231::alarm1_rate::once_per_second);
```
`example/main.cpp` is the full tour. libavr rides as the `libavr/` submodule,
pinned to the commit this driver builds against; `LIBAVR_ROOT` (cache or
environment) overrides it for development against a working tree:
```sh
git submodule update --init libavr
cmake --preset attiny85-generated
cmake --build --preset attiny85-generated
```
Presets cover attiny85/atmega328p in both libavr modes (generated and
reflect); `ctest` runs the consteval battery over the BCD, the hours
register's two formats, the weekday and the alarm rate encodings. The legacy
yazoalfa-based driver lives on the `master` branch.
The weekday register is derived from the date by default. A program that
assigns its own meaning to the device's 1..7 takes ownership of it, and no
write here touches it:
```cpp
using rtc = ds3231::device<bus, ds3231::weekday_source::external>;
```
An alarm arms its INT/SQW output unless told otherwise, and can be muted and
re-wired without re-arming:
```cpp
auto quiet = rtc::set_alarm2(at, ds3231::alarm2_rate::minutes_match,
ds3231::alarm_interrupt::off);
auto again = rtc::listen_alarm2();
```
## Atmel Studio
`master` carries a Studio solution, so this branch does too: `ide/ds3231.atsln`
builds `example/main.cpp` for both parts the presets cover, each to a
**byte-identical `.text`** against the CMake build (`check-flags.py` below is
what holds the flag sets equal, so the sizes are the presets' own), with the
flags mirrored by hand. CMake remains the build system.
`avrdevice` is a project-level property in Studio, so a part means a project, not
a configuration: `ide/atmega328p/` and `ide/attiny85/`. They need separate
directories rather than separate names — Studio builds into `<project
dir>/<Configuration>` whatever `OutputDirectory` says, so two projects sharing
one directory would also share one `example/main.o`, and building one after the
other without a rebuild would link the other part's object.
Studio finds libavr in the **submodule** at
`$(MSBuildProjectDirectory)\..\..\libavr\include` — correct by construction,
and anchored to the project because a plain relative path is resolved against
the generated makefile's directory (the configuration's output directory), not
the project's. There is no `LIBAVR_ROOT` escape hatch: a variable exported in a
shell is invisible to Studio launched from the Start menu — which is what the
submodule answers. It also needs a GCC 16.1 toolchain registered as flavour
`avr-g++-16.1.0`, nothing older reaching `-std=c++26`.
One generated file is required before the project will load, and one command
checks the flags have not drifted (both from libavr's `tools/atmelstudio/`):
```sh
for mcu in atmega328p attiny85; do
case $mcu in atmega328p) device=ATmega328P;; attiny85) device=ATtiny85;; esac
python libavr/tools/atmelstudio/componentinfo.py \
"ide/$mcu/ds3231-$mcu.componentinfo.xml" --device "$device"
python libavr/tools/atmelstudio/check-flags.py --solution ide/ds3231.atsln \
--project "ds3231-$mcu" \
--compile-commands "build/$mcu-generated/compile_commands.json" \
--log "build/as-$mcu.log"
done
```
One reference describes one part, hence `--project`. Release is what the gate
compares, the presets defining no debug build; Debug carries the `-Og
-gdwarf-4` pair libavr's own debug preset uses.
Differences from legacy: weekday-rate alarms now actually set the DY bit
(the old `setAlarmHelper` always cleared it), reads/writes are single
coherent bus transactions, and errors are reported instead of ignored.

22
ds3231.atsln Normal file
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@@ -0,0 +1,22 @@
Microsoft Visual Studio Solution File, Format Version 12.00
# Atmel Studio Solution File, Format Version 11.00
VisualStudioVersion = 14.0.25420.1
MinimumVisualStudioVersion = 10.0.40219.1
Project("{E66E83B9-2572-4076-B26E-6BE79FF3018A}") = "ds3231", "ds3231\ds3231.cppproj", "{DCE6C7E3-EE26-4D79-826B-08594B9AD897}"
EndProject
Global
GlobalSection(SolutionConfigurationPlatforms) = preSolution
Debug|AVR = Debug|AVR
Release|AVR = Release|AVR
EndGlobalSection
GlobalSection(ProjectConfigurationPlatforms) = postSolution
{DCE6C7E3-EE26-4D79-826B-08594B9AD897}.Debug|AVR.ActiveCfg = Debug|AVR
{DCE6C7E3-EE26-4D79-826B-08594B9AD897}.Debug|AVR.Build.0 = Debug|AVR
{DCE6C7E3-EE26-4D79-826B-08594B9AD897}.Release|AVR.ActiveCfg = Release|AVR
{DCE6C7E3-EE26-4D79-826B-08594B9AD897}.Release|AVR.Build.0 = Release|AVR
EndGlobalSection
GlobalSection(SolutionProperties) = preSolution
HideSolutionNode = FALSE
EndGlobalSection
EndGlobal

4
ds3231/clock.hpp Normal file
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@@ -0,0 +1,4 @@
#pragma once
#define F_CPU 16'000'000
#include <util/delay.h>

1
ds3231/ds3231 Submodule

Submodule ds3231/ds3231 added at 8a6170cb10

285
ds3231/ds3231.cppproj Normal file
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@@ -0,0 +1,285 @@
<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="14.0">
<PropertyGroup>
<SchemaVersion>2.0</SchemaVersion>
<ProjectVersion>7.0</ProjectVersion>
<ToolchainName>com.Atmel.AVRGCC8.CPP</ToolchainName>
<ProjectGuid>dce6c7e3-ee26-4d79-826b-08594b9ad897</ProjectGuid>
<avrdevice>ATmega328P</avrdevice>
<avrdeviceseries>none</avrdeviceseries>
<OutputType>Executable</OutputType>
<Language>CPP</Language>
<OutputFileName>$(MSBuildProjectName)</OutputFileName>
<OutputFileExtension>.elf</OutputFileExtension>
<OutputDirectory>$(MSBuildProjectDirectory)\$(Configuration)</OutputDirectory>
<AssemblyName>DailySafe</AssemblyName>
<Name>DailySafe</Name>
<RootNamespace>DailySafe</RootNamespace>
<ToolchainFlavour>avr-g++-9.1.0</ToolchainFlavour>
<KeepTimersRunning>true</KeepTimersRunning>
<OverrideVtor>false</OverrideVtor>
<CacheFlash>true</CacheFlash>
<ProgFlashFromRam>true</ProgFlashFromRam>
<RamSnippetAddress>0x20000000</RamSnippetAddress>
<UncachedRange />
<preserveEEPROM>true</preserveEEPROM>
<OverrideVtorValue>exception_table</OverrideVtorValue>
<BootSegment>2</BootSegment>
<ResetRule>0</ResetRule>
<eraseonlaunchrule>0</eraseonlaunchrule>
<EraseKey />
<avrtool>com.atmel.avrdbg.tool.atmelice</avrtool>
<avrtoolserialnumber>J41800099437</avrtoolserialnumber>
<avrdeviceexpectedsignature>0x1E950F</avrdeviceexpectedsignature>
<com_atmel_avrdbg_tool_stk500>
<ToolOptions>
<InterfaceProperties>
<IspClock>125000</IspClock>
</InterfaceProperties>
<InterfaceName>ISP</InterfaceName>
</ToolOptions>
<ToolType>com.atmel.avrdbg.tool.stk500</ToolType>
<ToolNumber>
</ToolNumber>
<ToolName>STK500</ToolName>
</com_atmel_avrdbg_tool_stk500>
<avrtoolinterface>ISP</avrtoolinterface>
<avrtoolinterfaceclock>125000</avrtoolinterfaceclock>
<AsfFrameworkConfig>
<framework-data xmlns="">
<options />
<configurations />
<files />
<documentation help="" />
<offline-documentation help="" />
<dependencies>
<content-extension eid="atmel.asf" uuidref="Atmel.ASF" version="3.47.0" />
</dependencies>
</framework-data>
</AsfFrameworkConfig>
<com_atmel_avrdbg_tool_atmelice>
<ToolOptions>
<InterfaceProperties>
<IspClock>125000</IspClock>
</InterfaceProperties>
<InterfaceName>ISP</InterfaceName>
</ToolOptions>
<ToolType>com.atmel.avrdbg.tool.atmelice</ToolType>
<ToolNumber>J41800099437</ToolNumber>
<ToolName>Atmel-ICE</ToolName>
</com_atmel_avrdbg_tool_atmelice>
<custom>
<ToolOptions>
<InterfaceProperties>
<IspClock>125000</IspClock>
</InterfaceProperties>
<InterfaceName>
</InterfaceName>
</ToolOptions>
<ToolType>custom</ToolType>
<ToolNumber>
</ToolNumber>
<ToolName>Custom Programming Tool</ToolName>
</custom>
<AAFDebugger>
<AAFDebugFiles>
<DebugFile>
<path>\Debug\ds3231.lss</path>
<AAFSetting>
<Label>Lss Files</Label>
<Extention>.lss</Extention>
<Regex>^\s*(?&lt;address&gt;[a-f0-9]*):\s*.*$</Regex>
<DebugEnabled>true</DebugEnabled>
<RegexGroups>address</RegexGroups>
<DebuggerExpression>$pc</DebuggerExpression>
</AAFSetting>
</DebugFile>
</AAFDebugFiles>
</AAFDebugger>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
<ToolchainSettings>
<AvrGccCpp>
<avrgcc.common.Device>-mmcu=atmega328p</avrgcc.common.Device>
<avrgcc.common.outputfiles.hex>True</avrgcc.common.outputfiles.hex>
<avrgcc.common.outputfiles.lss>True</avrgcc.common.outputfiles.lss>
<avrgcc.common.outputfiles.eep>True</avrgcc.common.outputfiles.eep>
<avrgcc.common.outputfiles.srec>True</avrgcc.common.outputfiles.srec>
<avrgcc.common.outputfiles.usersignatures>False</avrgcc.common.outputfiles.usersignatures>
<avrgcc.compiler.general.ChangeDefaultCharTypeUnsigned>True</avrgcc.compiler.general.ChangeDefaultCharTypeUnsigned>
<avrgcc.compiler.general.ChangeDefaultBitFieldUnsigned>True</avrgcc.compiler.general.ChangeDefaultBitFieldUnsigned>
<avrgcc.compiler.symbols.DefSymbols>
<ListValues>
<Value>NDEBUG</Value>
</ListValues>
</avrgcc.compiler.symbols.DefSymbols>
<avrgcc.compiler.directories.IncludePaths>
<ListValues>
<Value>%24(PackRepoDir)\Atmel\ATmega_DFP\1.4.346\include</Value>
</ListValues>
</avrgcc.compiler.directories.IncludePaths>
<avrgcc.compiler.optimization.level>Optimize for size (-Os)</avrgcc.compiler.optimization.level>
<avrgcc.compiler.optimization.AllocateBytesNeededForEnum>True</avrgcc.compiler.optimization.AllocateBytesNeededForEnum>
<avrgcc.compiler.warnings.AllWarnings>True</avrgcc.compiler.warnings.AllWarnings>
<avrgcc.compiler.warnings.ExtraWarnings>True</avrgcc.compiler.warnings.ExtraWarnings>
<avrgcc.compiler.warnings.Pedantic>True</avrgcc.compiler.warnings.Pedantic>
<avrgcc.compiler.miscellaneous.OtherFlags>-fno-threadsafe-statics -std=c11</avrgcc.compiler.miscellaneous.OtherFlags>
<avrgcccpp.compiler.general.ChangeDefaultCharTypeUnsigned>True</avrgcccpp.compiler.general.ChangeDefaultCharTypeUnsigned>
<avrgcccpp.compiler.general.ChangeDefaultBitFieldUnsigned>True</avrgcccpp.compiler.general.ChangeDefaultBitFieldUnsigned>
<avrgcccpp.compiler.symbols.DefSymbols>
<ListValues>
<Value>NDEBUG</Value>
</ListValues>
</avrgcccpp.compiler.symbols.DefSymbols>
<avrgcccpp.compiler.directories.IncludePaths>
<ListValues>
<Value>%24(PackRepoDir)\Atmel\ATmega_DFP\1.4.346\include</Value>
</ListValues>
</avrgcccpp.compiler.directories.IncludePaths>
<avrgcccpp.compiler.optimization.level>Optimize for size (-Os)</avrgcccpp.compiler.optimization.level>
<avrgcccpp.compiler.optimization.AllocateBytesNeededForEnum>True</avrgcccpp.compiler.optimization.AllocateBytesNeededForEnum>
<avrgcccpp.compiler.warnings.AllWarnings>True</avrgcccpp.compiler.warnings.AllWarnings>
<avrgcccpp.compiler.warnings.Pedantic>True</avrgcccpp.compiler.warnings.Pedantic>
<avrgcccpp.compiler.miscellaneous.OtherFlags>-fno-threadsafe-statics -Wextra -std=c++17</avrgcccpp.compiler.miscellaneous.OtherFlags>
<avrgcccpp.linker.libraries.Libraries>
<ListValues>
<Value>libm</Value>
</ListValues>
</avrgcccpp.linker.libraries.Libraries>
<avrgcccpp.assembler.general.IncludePaths>
<ListValues>
<Value>%24(PackRepoDir)\Atmel\ATmega_DFP\1.4.346\include</Value>
</ListValues>
</avrgcccpp.assembler.general.IncludePaths>
</AvrGccCpp>
</ToolchainSettings>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
<ToolchainSettings>
<AvrGccCpp>
<avrgcc.common.Device>-mmcu=atmega328p</avrgcc.common.Device>
<avrgcc.common.outputfiles.hex>True</avrgcc.common.outputfiles.hex>
<avrgcc.common.outputfiles.lss>True</avrgcc.common.outputfiles.lss>
<avrgcc.common.outputfiles.eep>True</avrgcc.common.outputfiles.eep>
<avrgcc.common.outputfiles.srec>True</avrgcc.common.outputfiles.srec>
<avrgcc.common.outputfiles.usersignatures>False</avrgcc.common.outputfiles.usersignatures>
<avrgcc.compiler.general.ChangeDefaultCharTypeUnsigned>True</avrgcc.compiler.general.ChangeDefaultCharTypeUnsigned>
<avrgcc.compiler.general.ChangeDefaultBitFieldUnsigned>True</avrgcc.compiler.general.ChangeDefaultBitFieldUnsigned>
<avrgcc.compiler.symbols.DefSymbols>
<ListValues>
<Value>DEBUG</Value>
</ListValues>
</avrgcc.compiler.symbols.DefSymbols>
<avrgcc.compiler.directories.IncludePaths>
<ListValues>
<Value>%24(PackRepoDir)\Atmel\ATmega_DFP\1.4.346\include</Value>
</ListValues>
</avrgcc.compiler.directories.IncludePaths>
<avrgcc.compiler.optimization.level>Optimize (-O1)</avrgcc.compiler.optimization.level>
<avrgcc.compiler.optimization.AllocateBytesNeededForEnum>True</avrgcc.compiler.optimization.AllocateBytesNeededForEnum>
<avrgcc.compiler.optimization.DebugLevel>Maximum (-g3)</avrgcc.compiler.optimization.DebugLevel>
<avrgcc.compiler.warnings.AllWarnings>True</avrgcc.compiler.warnings.AllWarnings>
<avrgcc.compiler.warnings.ExtraWarnings>True</avrgcc.compiler.warnings.ExtraWarnings>
<avrgcc.compiler.warnings.Pedantic>True</avrgcc.compiler.warnings.Pedantic>
<avrgcc.compiler.miscellaneous.OtherFlags>-fno-threadsafe-statics -std=c11</avrgcc.compiler.miscellaneous.OtherFlags>
<avrgcccpp.compiler.general.ChangeDefaultCharTypeUnsigned>True</avrgcccpp.compiler.general.ChangeDefaultCharTypeUnsigned>
<avrgcccpp.compiler.general.ChangeDefaultBitFieldUnsigned>True</avrgcccpp.compiler.general.ChangeDefaultBitFieldUnsigned>
<avrgcccpp.compiler.symbols.DefSymbols>
<ListValues>
<Value>DEBUG</Value>
</ListValues>
</avrgcccpp.compiler.symbols.DefSymbols>
<avrgcccpp.compiler.directories.IncludePaths>
<ListValues>
<Value>%24(PackRepoDir)\Atmel\ATmega_DFP\1.4.346\include</Value>
</ListValues>
</avrgcccpp.compiler.directories.IncludePaths>
<avrgcccpp.compiler.optimization.level>Optimize debugging experience (-Og)</avrgcccpp.compiler.optimization.level>
<avrgcccpp.compiler.optimization.AllocateBytesNeededForEnum>True</avrgcccpp.compiler.optimization.AllocateBytesNeededForEnum>
<avrgcccpp.compiler.optimization.DebugLevel>Maximum (-g3)</avrgcccpp.compiler.optimization.DebugLevel>
<avrgcccpp.compiler.warnings.AllWarnings>True</avrgcccpp.compiler.warnings.AllWarnings>
<avrgcccpp.compiler.warnings.Pedantic>True</avrgcccpp.compiler.warnings.Pedantic>
<avrgcccpp.compiler.miscellaneous.OtherFlags>-fno-threadsafe-statics -Wextra -std=c++17</avrgcccpp.compiler.miscellaneous.OtherFlags>
<avrgcccpp.linker.libraries.Libraries>
<ListValues>
<Value>libm</Value>
</ListValues>
</avrgcccpp.linker.libraries.Libraries>
<avrgcccpp.assembler.general.IncludePaths>
<ListValues>
<Value>%24(PackRepoDir)\Atmel\ATmega_DFP\1.4.346\include</Value>
</ListValues>
</avrgcccpp.assembler.general.IncludePaths>
<avrgcccpp.assembler.debugging.DebugLevel>Default (-Wa,-g)</avrgcccpp.assembler.debugging.DebugLevel>
</AvrGccCpp>
</ToolchainSettings>
</PropertyGroup>
<ItemGroup>
<Compile Include="clock.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="ds3231\alarms.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="ds3231\ds3231.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="ds3231\flags.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="ds3231\registers.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="flash\flash.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="i2c\hardware.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="i2c\i2c.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="io\io.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="main.cpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="uart\config.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="uart\hardware.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="uart\hardware0.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="uart\hardware1.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="uart\software.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="uart\uart.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="util\func.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="util\type.hpp">
<SubType>compile</SubType>
</Compile>
<Compile Include="util\util.hpp">
<SubType>compile</SubType>
</Compile>
</ItemGroup>
<ItemGroup>
<Folder Include="ds3231" />
<Folder Include="io" />
<Folder Include="flash" />
<Folder Include="i2c" />
<Folder Include="util" />
<Folder Include="uart" />
</ItemGroup>
<Import Project="$(AVRSTUDIO_EXE_PATH)\\Vs\\Compiler.targets" />
</Project>

1
ds3231/flash Submodule

Submodule ds3231/flash added at 6edb2e5a21

1
ds3231/i2c Submodule

Submodule ds3231/i2c added at 8af5afd00d

1
ds3231/io Submodule

Submodule ds3231/io added at 80de36ee7e

188
ds3231/main.cpp Normal file
View File

@@ -0,0 +1,188 @@
#include "clock.hpp"
#include <stdlib.h>
#include "ds3231/ds3231.hpp"
#include "uart/uart.hpp"
using uart_t = uart::Uart0<>;
REGISTER_UART0_INT_VECTORS(uart_t);
static inline bool isEuDst(const rtc::DateTime &dateTime)
{
constexpr auto calcDstBegin = [](const auto &year) {
const auto beginDay = (31 - ((((5 * year) / 4) + 4) % 7));
return beginDay;
};
constexpr auto calcDstEnd = [](const auto &year) {
const auto endDay = (31 - ((((5 * year) / 4) + 1) % 7));
return endDay;
};
if (dateTime.month > 10 || dateTime.month < 3)
return false;
else if (dateTime.month > 3 && dateTime.month < 10)
return true;
else if (dateTime.month == 3) {
if (dateTime.day > calcDstBegin(dateTime.year)) {
return true;
} else if (dateTime.day == calcDstBegin(dateTime.year) && dateTime.hour >= 1)
return true;
return false;
}
// month == 10
if (dateTime.day < calcDstEnd(dateTime.year)) {
return true;
} else if (dateTime.day == calcDstEnd(dateTime.year) && dateTime.hour < 1)
return true;
return false;
}
inline uart_t &operator<<(uart_t &serial, const rtc::DateTime &dateTime)
{
serial.txNumber<uint16_t, 10, 4>(dateTime.year);
serial << '-';
serial.txNumber<uint8_t, 10, 2>(dateTime.month);
serial << '-';
serial.txNumber<uint8_t, 10, 2>(dateTime.day);
serial << ' ';
serial.txNumber<uint8_t, 10, 2>(dateTime.hour);
serial << ':';
serial.txNumber<uint8_t, 10, 2>(dateTime.minute);
serial << ':';
serial.txNumber<uint8_t, 10, 2>(dateTime.second);
return serial;
}
static inline void printLocalTime(const rtc::DateTime &dateTime)
{
const auto dst = isEuDst(dateTime);
uart_t serial;
serial << dateTime << (dst ? F(" +2") : F(" +1")) << F("\r\n");
}
static inline size_t receiveLine(char *buffer, const size_t maxLength)
{
uart_t serial;
size_t received = 0;
while (received < maxLength) {
if (serial.rxByte(*reinterpret_cast<uint8_t *>(&buffer[received]))) {
++received;
if (buffer[received - 1] == '\r' || buffer[received - 1] == '\n')
break;
}
}
return received;
}
static inline rtc::DateTime receiveTime()
{
uart_t serial;
rtc::DateTime dateTime;
constexpr auto BUF_LEN = 8;
char receiveBuffer[BUF_LEN];
serial << F("Enter year: ");
auto receivedLen = receiveLine(receiveBuffer, BUF_LEN);
receiveBuffer[receivedLen] = '\0';
dateTime.year = atoi(receiveBuffer);
serial << F("\r\nEnter month: ");
receivedLen = receiveLine(receiveBuffer, BUF_LEN);
receiveBuffer[receivedLen] = '\0';
dateTime.month = atoi(receiveBuffer);
serial << F("\r\nEnter date: ");
receivedLen = receiveLine(receiveBuffer, BUF_LEN);
receiveBuffer[receivedLen] = '\0';
dateTime.day = atoi(receiveBuffer);
serial << F("\r\nEnter hour: ");
receivedLen = receiveLine(receiveBuffer, BUF_LEN);
receiveBuffer[receivedLen] = '\0';
dateTime.hour = atoi(receiveBuffer);
serial << F("\r\nEnter minute: ");
receivedLen = receiveLine(receiveBuffer, BUF_LEN);
receiveBuffer[receivedLen] = '\0';
dateTime.minute = atoi(receiveBuffer);
serial << F("\r\nEnter second: ");
receivedLen = receiveLine(receiveBuffer, BUF_LEN);
receiveBuffer[receivedLen] = '\0';
dateTime.second = atoi(receiveBuffer);
serial << F("\r\n");
return dateTime;
}
int main()
{
uart_t serial;
rtc::DS3231<i2c::Hardware<100'000>, false> ds3231;
io::Pin<io::P::C3> rtcPwr;
rtcPwr = false;
rtcPwr.dir(io::Dir::OUT);
rtcPwr = true;
_delay_ms(1000);
ds3231.init();
serial.init();
ds3231.clearAlarm1();
ds3231.clearAlarm2();
rtc::DateTime alarmTime;
alarmTime.second = 17;
alarmTime.minute = 54;
ds3231.setAlarm1(alarmTime, rtc::Alarm1Rate::WHEN_S_MATCH);
ds3231.setAlarm2(alarmTime, rtc::Alarm2Rate::WHEN_M_MATCH);
auto oldDate = ds3231.getDateTime();
while (true) {
const auto date = ds3231.getDateTime();
if (oldDate != date) {
oldDate = date;
printLocalTime(date);
}
if (ds3231.checkAlarm1()) {
serial << F("Alarm1!\r\n");
ds3231.clearAlarm1();
}
if (ds3231.checkAlarm2()) {
serial << F("Alarm2!\r\n");
ds3231.clearAlarm2();
}
uint8_t receivedByte;
if (serial.rxByte(receivedByte)) {
if (receivedByte == 's') {
const auto newDate = receiveTime();
ds3231.setDateTime(newDate);
} else if (receivedByte == '1') {
const auto alarm = ds3231.getAlarm1();
serial << F("Alarm1: ") << alarm << F("\r\n");
} else if (receivedByte == '2') {
const auto alarm = ds3231.getAlarm2();
serial << F("Alarm2: ") << alarm << F("\r\n");
} else
serial << F("Invalid input: ") << static_cast<char>(receivedByte) << F("\r\n");
}
}
return 0;
}

1
ds3231/uart Submodule

Submodule ds3231/uart added at 119de32445

1
ds3231/util Submodule

Submodule ds3231/util added at 81b3ae244c

View File

@@ -1,3 +0,0 @@
add_executable(clock main.cpp)
target_link_libraries(clock PRIVATE ds3231)
add_custom_command(TARGET clock POST_BUILD COMMAND ${CMAKE_SIZE} $<TARGET_FILE:clock>)

View File

@@ -1,37 +0,0 @@
#include <ds3231/ds3231.hpp>
#include <libavr/libavr.hpp>
using namespace avr::literals;
// One source for the tiny85 (open-drain software I2C on the USI pins) and
// the mega328P (TWI hardware). On first power-up the clock is seeded and
// alarm 1 armed; then the LED mirrors the seconds parity - a stuck LED
// means bus errors.
using dev = avr::device<{.clock = 8_MHz}>;
using bus = dev::i2c<{.frequency = 100_kHz}>;
using rtc = ds3231::device<bus>;
using led = dev::output<avr::pb3>;
int main()
{
avr::init<bus, led>();
if (auto stopped = rtc::oscillator_stopped(); stopped.value_or(false)) {
// A failed seed leaves the LED dark before the loop ever runs - the
// same signal a stuck bus gives it below.
const bool seeded = rtc::write_clock({{2026, 1, 1}, {12, 0, 0}}) &&
rtc::set_alarm1({}, ds3231::alarm1_rate::once_per_second) &&
rtc::clear_oscillator_stopped();
led::write(seeded);
}
while (true) {
if (auto now = rtc::read_clock(); now.has_value()) {
led::write(now->second % 2 == 0);
}
if (auto fired = rtc::alarm1_fired(); fired.value_or(false) && !rtc::clear_alarm1()) {
led::clear(); // a clear that failed holds the LED dark, like any bus error
}
dev::delay<100_ms>();
}
}

View File

@@ -1,108 +0,0 @@
<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="14.0">
<PropertyGroup>
<SchemaVersion>2.0</SchemaVersion>
<ProjectVersion>7.0</ProjectVersion>
<ToolchainName>com.Atmel.AVRGCC8.CPP</ToolchainName>
<ProjectGuid>7b3e5a41-9c26-4d18-8f52-6a0d31c74be9</ProjectGuid>
<avrdevice>ATmega328P</avrdevice>
<avrdeviceseries>none</avrdeviceseries>
<OutputType>Executable</OutputType>
<Language>CPP</Language>
<OutputFileName>$(MSBuildProjectName)</OutputFileName>
<OutputFileExtension>.elf</OutputFileExtension>
<OutputDirectory>$(MSBuildProjectDirectory)\$(Configuration)</OutputDirectory>
<AssemblyName>ds3231-atmega328p</AssemblyName>
<Name>ds3231-atmega328p</Name>
<RootNamespace>ds3231</RootNamespace>
<ToolchainFlavour>avr-g++-16.1.0</ToolchainFlavour>
<KeepTimersRunning>true</KeepTimersRunning>
<OverrideVtor>false</OverrideVtor>
<CacheFlash>true</CacheFlash>
<ProgFlashFromRam>true</ProgFlashFromRam>
<RamSnippetAddress>0x20000000</RamSnippetAddress>
<UncachedRange />
<preserveEEPROM>true</preserveEEPROM>
<OverrideVtorValue>exception_table</OverrideVtorValue>
<BootSegment>2</BootSegment>
<ResetRule>0</ResetRule>
<eraseonlaunchrule>0</eraseonlaunchrule>
<EraseKey />
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
<ToolchainSettings>
<AvrGccCpp>
<avrgcc.common.Device>-mmcu=atmega328p</avrgcc.common.Device>
<avrgcc.common.outputfiles.hex>True</avrgcc.common.outputfiles.hex>
<avrgcc.common.outputfiles.lss>True</avrgcc.common.outputfiles.lss>
<avrgcc.common.outputfiles.eep>True</avrgcc.common.outputfiles.eep>
<avrgcc.common.outputfiles.srec>True</avrgcc.common.outputfiles.srec>
<avrgcc.common.outputfiles.usersignatures>False</avrgcc.common.outputfiles.usersignatures>
<avrgcccpp.compiler.symbols.DefSymbols>
<ListValues>
<Value>NDEBUG</Value>
</ListValues>
</avrgcccpp.compiler.symbols.DefSymbols>
<avrgcccpp.compiler.directories.IncludePaths>
<ListValues>
<Value>$(MSBuildProjectDirectory)\..\..\include</Value>
<Value>$(MSBuildProjectDirectory)\..\..\libavr\include</Value>
</ListValues>
</avrgcccpp.compiler.directories.IncludePaths>
<avrgcccpp.compiler.optimization.level>Optimize for size (-Os)</avrgcccpp.compiler.optimization.level>
<avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>
<avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>
<avrgcccpp.compiler.warnings.AllWarnings>True</avrgcccpp.compiler.warnings.AllWarnings>
<avrgcccpp.compiler.miscellaneous.OtherFlags>-std=c++26 -Wextra -mrelax -fno-exceptions -fno-rtti -fno-threadsafe-statics</avrgcccpp.compiler.miscellaneous.OtherFlags>
<avrgcccpp.linker.optimization.GarbageCollectUnusedSections>True</avrgcccpp.linker.optimization.GarbageCollectUnusedSections>
<avrgcccpp.linker.miscellaneous.LinkerFlags>-mrelax</avrgcccpp.linker.miscellaneous.LinkerFlags>
</AvrGccCpp>
</ToolchainSettings>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
<ToolchainSettings>
<AvrGccCpp>
<avrgcc.common.Device>-mmcu=atmega328p</avrgcc.common.Device>
<avrgcc.common.outputfiles.hex>True</avrgcc.common.outputfiles.hex>
<avrgcc.common.outputfiles.lss>True</avrgcc.common.outputfiles.lss>
<avrgcc.common.outputfiles.eep>True</avrgcc.common.outputfiles.eep>
<avrgcc.common.outputfiles.srec>True</avrgcc.common.outputfiles.srec>
<avrgcc.common.outputfiles.usersignatures>False</avrgcc.common.outputfiles.usersignatures>
<avrgcccpp.compiler.symbols.DefSymbols>
<ListValues>
<Value>DEBUG</Value>
</ListValues>
</avrgcccpp.compiler.symbols.DefSymbols>
<avrgcccpp.compiler.directories.IncludePaths>
<ListValues>
<Value>$(MSBuildProjectDirectory)\..\..\include</Value>
<Value>$(MSBuildProjectDirectory)\..\..\libavr\include</Value>
</ListValues>
</avrgcccpp.compiler.directories.IncludePaths>
<avrgcccpp.compiler.optimization.level>Optimize debugging experience (-Og)</avrgcccpp.compiler.optimization.level>
<avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>
<avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>
<avrgcccpp.compiler.warnings.AllWarnings>True</avrgcccpp.compiler.warnings.AllWarnings>
<avrgcccpp.compiler.miscellaneous.OtherFlags>-std=c++26 -Wextra -mrelax -fno-exceptions -fno-rtti -fno-threadsafe-statics -gdwarf-4</avrgcccpp.compiler.miscellaneous.OtherFlags>
<avrgcccpp.linker.optimization.GarbageCollectUnusedSections>True</avrgcccpp.linker.optimization.GarbageCollectUnusedSections>
<avrgcccpp.linker.miscellaneous.LinkerFlags>-mrelax</avrgcccpp.linker.miscellaneous.LinkerFlags>
</AvrGccCpp>
</ToolchainSettings>
</PropertyGroup>
<ItemGroup>
<Compile Include="..\..\example\main.cpp">
<SubType>compile</SubType>
<Link>example\main.cpp</Link>
</Compile>
<Compile Include="..\..\include\ds3231\ds3231.hpp">
<SubType>compile</SubType>
<Link>include\ds3231\ds3231.hpp</Link>
</Compile>
</ItemGroup>
<ItemGroup>
<Folder Include="example" />
<Folder Include="include" />
<Folder Include="include\ds3231" />
</ItemGroup>
<Import Project="$(AVRSTUDIO_EXE_PATH)\Vs\Compiler.targets" />
</Project>

View File

@@ -1,108 +0,0 @@
<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="14.0">
<PropertyGroup>
<SchemaVersion>2.0</SchemaVersion>
<ProjectVersion>7.0</ProjectVersion>
<ToolchainName>com.Atmel.AVRGCC8.CPP</ToolchainName>
<ProjectGuid>1d84c0f7-52b9-4a63-b7e1-9f2c48d5a306</ProjectGuid>
<avrdevice>ATtiny85</avrdevice>
<avrdeviceseries>none</avrdeviceseries>
<OutputType>Executable</OutputType>
<Language>CPP</Language>
<OutputFileName>$(MSBuildProjectName)</OutputFileName>
<OutputFileExtension>.elf</OutputFileExtension>
<OutputDirectory>$(MSBuildProjectDirectory)\$(Configuration)</OutputDirectory>
<AssemblyName>ds3231-attiny85</AssemblyName>
<Name>ds3231-attiny85</Name>
<RootNamespace>ds3231</RootNamespace>
<ToolchainFlavour>avr-g++-16.1.0</ToolchainFlavour>
<KeepTimersRunning>true</KeepTimersRunning>
<OverrideVtor>false</OverrideVtor>
<CacheFlash>true</CacheFlash>
<ProgFlashFromRam>true</ProgFlashFromRam>
<RamSnippetAddress>0x20000000</RamSnippetAddress>
<UncachedRange />
<preserveEEPROM>true</preserveEEPROM>
<OverrideVtorValue>exception_table</OverrideVtorValue>
<BootSegment>2</BootSegment>
<ResetRule>0</ResetRule>
<eraseonlaunchrule>0</eraseonlaunchrule>
<EraseKey />
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
<ToolchainSettings>
<AvrGccCpp>
<avrgcc.common.Device>-mmcu=attiny85</avrgcc.common.Device>
<avrgcc.common.outputfiles.hex>True</avrgcc.common.outputfiles.hex>
<avrgcc.common.outputfiles.lss>True</avrgcc.common.outputfiles.lss>
<avrgcc.common.outputfiles.eep>True</avrgcc.common.outputfiles.eep>
<avrgcc.common.outputfiles.srec>True</avrgcc.common.outputfiles.srec>
<avrgcc.common.outputfiles.usersignatures>False</avrgcc.common.outputfiles.usersignatures>
<avrgcccpp.compiler.symbols.DefSymbols>
<ListValues>
<Value>NDEBUG</Value>
</ListValues>
</avrgcccpp.compiler.symbols.DefSymbols>
<avrgcccpp.compiler.directories.IncludePaths>
<ListValues>
<Value>$(MSBuildProjectDirectory)\..\..\include</Value>
<Value>$(MSBuildProjectDirectory)\..\..\libavr\include</Value>
</ListValues>
</avrgcccpp.compiler.directories.IncludePaths>
<avrgcccpp.compiler.optimization.level>Optimize for size (-Os)</avrgcccpp.compiler.optimization.level>
<avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>
<avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>
<avrgcccpp.compiler.warnings.AllWarnings>True</avrgcccpp.compiler.warnings.AllWarnings>
<avrgcccpp.compiler.miscellaneous.OtherFlags>-std=c++26 -Wextra -mrelax -fno-exceptions -fno-rtti -fno-threadsafe-statics</avrgcccpp.compiler.miscellaneous.OtherFlags>
<avrgcccpp.linker.optimization.GarbageCollectUnusedSections>True</avrgcccpp.linker.optimization.GarbageCollectUnusedSections>
<avrgcccpp.linker.miscellaneous.LinkerFlags>-mrelax</avrgcccpp.linker.miscellaneous.LinkerFlags>
</AvrGccCpp>
</ToolchainSettings>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
<ToolchainSettings>
<AvrGccCpp>
<avrgcc.common.Device>-mmcu=attiny85</avrgcc.common.Device>
<avrgcc.common.outputfiles.hex>True</avrgcc.common.outputfiles.hex>
<avrgcc.common.outputfiles.lss>True</avrgcc.common.outputfiles.lss>
<avrgcc.common.outputfiles.eep>True</avrgcc.common.outputfiles.eep>
<avrgcc.common.outputfiles.srec>True</avrgcc.common.outputfiles.srec>
<avrgcc.common.outputfiles.usersignatures>False</avrgcc.common.outputfiles.usersignatures>
<avrgcccpp.compiler.symbols.DefSymbols>
<ListValues>
<Value>DEBUG</Value>
</ListValues>
</avrgcccpp.compiler.symbols.DefSymbols>
<avrgcccpp.compiler.directories.IncludePaths>
<ListValues>
<Value>$(MSBuildProjectDirectory)\..\..\include</Value>
<Value>$(MSBuildProjectDirectory)\..\..\libavr\include</Value>
</ListValues>
</avrgcccpp.compiler.directories.IncludePaths>
<avrgcccpp.compiler.optimization.level>Optimize debugging experience (-Og)</avrgcccpp.compiler.optimization.level>
<avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareFunctionsForGarbageCollection>
<avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>True</avrgcccpp.compiler.optimization.PrepareDataForGarbageCollection>
<avrgcccpp.compiler.warnings.AllWarnings>True</avrgcccpp.compiler.warnings.AllWarnings>
<avrgcccpp.compiler.miscellaneous.OtherFlags>-std=c++26 -Wextra -mrelax -fno-exceptions -fno-rtti -fno-threadsafe-statics -gdwarf-4</avrgcccpp.compiler.miscellaneous.OtherFlags>
<avrgcccpp.linker.optimization.GarbageCollectUnusedSections>True</avrgcccpp.linker.optimization.GarbageCollectUnusedSections>
<avrgcccpp.linker.miscellaneous.LinkerFlags>-mrelax</avrgcccpp.linker.miscellaneous.LinkerFlags>
</AvrGccCpp>
</ToolchainSettings>
</PropertyGroup>
<ItemGroup>
<Compile Include="..\..\example\main.cpp">
<SubType>compile</SubType>
<Link>example\main.cpp</Link>
</Compile>
<Compile Include="..\..\include\ds3231\ds3231.hpp">
<SubType>compile</SubType>
<Link>include\ds3231\ds3231.hpp</Link>
</Compile>
</ItemGroup>
<ItemGroup>
<Folder Include="example" />
<Folder Include="include" />
<Folder Include="include\ds3231" />
</ItemGroup>
<Import Project="$(AVRSTUDIO_EXE_PATH)\Vs\Compiler.targets" />
</Project>

View File

@@ -1,28 +0,0 @@
Microsoft Visual Studio Solution File, Format Version 12.00
# Atmel Studio Solution File, Format Version 11.00
VisualStudioVersion = 14.0.23107.0
MinimumVisualStudioVersion = 10.0.40219.1
Project("{E66E83B9-2572-4076-B26E-6BE79FF3018A}") = "ds3231-atmega328p", "atmega328p\ds3231-atmega328p.cppproj", "{7B3E5A41-9C26-4D18-8F52-6A0D31C74BE9}"
EndProject
Project("{E66E83B9-2572-4076-B26E-6BE79FF3018A}") = "ds3231-attiny85", "attiny85\ds3231-attiny85.cppproj", "{1D84C0F7-52B9-4A63-B7E1-9F2C48D5A306}"
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{1D84C0F7-52B9-4A63-B7E1-9F2C48D5A306}.Debug|AVR.Build.0 = Debug|AVR
{1D84C0F7-52B9-4A63-B7E1-9F2C48D5A306}.Release|AVR.ActiveCfg = Release|AVR
{1D84C0F7-52B9-4A63-B7E1-9F2C48D5A306}.Release|AVR.Build.0 = Release|AVR
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GlobalSection(SolutionProperties) = preSolution
HideSolutionNode = FALSE
EndGlobalSection
EndGlobal

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@@ -1,375 +0,0 @@
#pragma once
#include <array>
#include <cstdint>
#include <expected>
#include <span>
#include <libavr/i2c.hpp>
namespace ds3231 {
using avr::i2c::error;
using avr::i2c::status;
template <typename T>
using result = std::expected<T, error>;
struct date {
std::uint16_t year; // 2000..2099
std::uint8_t month; // 1..12
std::uint8_t day; // 1..31 (weekday 1..7 in weekday-alarm reads)
friend constexpr bool operator==(const date &, const date &) = default;
};
struct time_of_day {
std::uint8_t hour; // 0..23
std::uint8_t minute;
std::uint8_t second;
friend constexpr bool operator==(const time_of_day &, const time_of_day &) = default;
};
struct date_time : date, time_of_day {
friend constexpr bool operator==(const date_time &, const date_time &) = default;
};
// Alarm match rates (datasheet Table 2). Alarm 2 has no seconds register
// and fires at :00 of the matching minute.
enum class alarm1_rate : std::uint8_t {
once_per_second = 0b01111,
seconds_match = 0b01110,
minutes_seconds_match = 0b01100,
time_match = 0b01000,
date_time_match = 0b00000,
weekday_time_match = 0b10000,
};
// Who owns the weekday register. The device counts 1..7 with a free epoch and
// maintains nothing itself, so either this driver derives it from the date on
// every write, or the register belongs to the program and no write here
// touches it - which is what a caller that assigns its own meaning to those
// seven values needs.
enum class weekday_source : std::uint8_t { computed, external };
// Whether arming an alarm also wires its INT/SQW output. `off` is not
// silence about the bit - it clears A1IE/A2IE, so an alarm armed with the
// interrupt on and re-armed with it off stops driving the pin.
enum class alarm_interrupt : std::uint8_t { off, on };
enum class alarm2_rate : std::uint8_t {
once_per_minute = 0b0111,
minutes_match = 0b0110,
time_match = 0b0100,
date_time_match = 0b0000,
weekday_time_match = 0b1000,
};
namespace detail {
constexpr std::uint8_t to_bcd(std::uint8_t value)
{
return static_cast<std::uint8_t>(((value / 10) << 4) | (value % 10));
}
constexpr std::uint8_t from_bcd(std::uint8_t value)
{
return static_cast<std::uint8_t>((value >> 4) * 10 + (value & 0x0f));
}
// Hours register: bit 6 selects 12-hour mode, bit 5 is then PM. Writes
// always use 24-hour form; reads accept either.
constexpr std::uint8_t hours_from_reg(std::uint8_t reg)
{
if (reg & 0x40) {
auto hour = from_bcd(reg & 0x1f);
bool pm = reg & 0x20;
if (hour == 12) {
return pm ? 12 : 0;
}
return static_cast<std::uint8_t>(pm ? hour + 12 : hour);
}
return from_bcd(reg & 0x3f);
}
// Sakamoto's method; the device counts weekdays 1..7 with a free epoch,
// this maps Sunday to 1.
constexpr std::uint8_t weekday(std::uint16_t year, std::uint8_t month, std::uint8_t day)
{
static constexpr auto offsets = std::to_array<std::uint8_t>({0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4});
if (month < 3) {
--year;
}
return static_cast<std::uint8_t>((year + year / 4 - year / 100 + year / 400 + offsets[month - 1] + day) % 7 + 1);
}
} // namespace detail
// The one bus address a DS3231 answers on - hardwired in the die, no
// address pins (datasheet 19-5170, "I2C interface").
inline constexpr std::uint8_t bus_address = 0x68;
// Maxim DS3231 RTC on any libavr i2c bus (register map: datasheet
// 19-5170 Table 1): the master role is taken from the bus's own
// resolution, so a declared `dev::i2c<...>` is handed over whole. Every
// call is one bus transaction; errors surface as std::expected. Weekday
// registers are derived from the date unless the program owns them.
template <typename Bus, weekday_source Weekday = weekday_source::computed>
class device {
static constexpr bool computes_weekday = Weekday == weekday_source::computed;
using dev = avr::i2c::device<typename Bus::master, bus_address>;
static constexpr std::uint8_t reg_clock = 0x00;
static constexpr std::uint8_t reg_alarm1 = 0x07;
static constexpr std::uint8_t reg_alarm2 = 0x0b;
static constexpr std::uint8_t reg_control = 0x0e;
static constexpr std::uint8_t reg_status = 0x0f;
static constexpr std::uint8_t reg_temp = 0x11;
static constexpr std::uint8_t a1ie = 0x01, a2ie = 0x02, intcn = 0x04, bbsqw = 0x40;
static constexpr std::uint8_t a1f = 0x01, a2f = 0x02, osf = 0x80;
public:
[[nodiscard]] static result<date_time> read_clock()
{
std::array<std::uint8_t, 7> raw;
if (auto s = dev::read_regs(reg_clock, raw); !s) {
return std::unexpected(s.error());
}
date_time now;
static_cast<time_of_day &>(now) = decode_time(raw);
now.day = detail::from_bcd(raw[4] & 0x3f);
now.month = detail::from_bcd(raw[5] & 0x1f);
now.year = static_cast<std::uint16_t>(2000 + detail::from_bcd(raw[6]));
return now;
}
[[nodiscard]] static result<date> read_date()
{
auto now = read_clock();
if (!now) {
return std::unexpected(now.error());
}
return static_cast<date>(*now);
}
[[nodiscard]] static result<time_of_day> read_time()
{
std::array<std::uint8_t, 3> raw;
if (auto s = dev::read_regs(reg_clock, raw); !s) {
return std::unexpected(s.error());
}
return decode_time(raw);
}
[[nodiscard]] static status write_clock(const date_time &now)
{
if constexpr (!computes_weekday) {
// Two transactions, because the weekday register sits between the
// time and the date and this mode may not write it.
if (auto s = write_time(now); !s) {
return s;
}
return write_date(now);
} else {
std::array raw{detail::to_bcd(now.second),
detail::to_bcd(now.minute),
detail::to_bcd(now.hour),
detail::weekday(now.year, now.month, now.day),
detail::to_bcd(now.day),
detail::to_bcd(now.month),
detail::to_bcd(static_cast<std::uint8_t>(now.year % 100))};
return dev::write_regs(reg_clock, raw);
}
}
[[nodiscard]] static status write_date(const date &value)
{
if constexpr (computes_weekday) {
std::array raw{detail::weekday(value.year, value.month, value.day), detail::to_bcd(value.day),
detail::to_bcd(value.month), detail::to_bcd(static_cast<std::uint8_t>(value.year % 100))};
return dev::write_regs(reg_clock + 3, raw);
} else {
std::array raw{detail::to_bcd(value.day), detail::to_bcd(value.month),
detail::to_bcd(static_cast<std::uint8_t>(value.year % 100))};
return dev::write_regs(reg_clock + 4, raw);
}
}
[[nodiscard]] static status write_time(const time_of_day &value)
{
std::array raw{detail::to_bcd(value.second), detail::to_bcd(value.minute), detail::to_bcd(value.hour)};
return dev::write_regs(reg_clock, raw);
}
// Alarm times use .day as the date of month, or as weekday 1..7 with
// the weekday_time_match rates.
[[nodiscard]] static status set_alarm1(const date_time &at, alarm1_rate rate,
alarm_interrupt interrupt = alarm_interrupt::on)
{
auto m = static_cast<std::uint8_t>(rate);
std::array raw{static_cast<std::uint8_t>(detail::to_bcd(at.second) | ((m & 1) << 7)),
static_cast<std::uint8_t>(detail::to_bcd(at.minute) | (((m >> 1) & 1) << 7)),
static_cast<std::uint8_t>(detail::to_bcd(at.hour) | (((m >> 2) & 1) << 7)),
static_cast<std::uint8_t>(day_date(at.day, rate == alarm1_rate::weekday_time_match) |
(((m >> 3) & 1) << 7))};
if (auto s = dev::write_regs(reg_alarm1, raw); !s) {
return s;
}
return set_alarm_interrupt(a1ie, interrupt);
}
[[nodiscard]] static status set_alarm2(const date_time &at, alarm2_rate rate,
alarm_interrupt interrupt = alarm_interrupt::on)
{
auto m = static_cast<std::uint8_t>(rate);
std::array raw{static_cast<std::uint8_t>(detail::to_bcd(at.minute) | ((m & 1) << 7)),
static_cast<std::uint8_t>(detail::to_bcd(at.hour) | (((m >> 1) & 1) << 7)),
static_cast<std::uint8_t>(day_date(at.day, rate == alarm2_rate::weekday_time_match) |
(((m >> 2) & 1) << 7))};
if (auto s = dev::write_regs(reg_alarm2, raw); !s) {
return s;
}
return set_alarm_interrupt(a2ie, interrupt);
}
[[nodiscard]] static result<date_time> read_alarm1()
{
std::array<std::uint8_t, 4> raw;
if (auto s = dev::read_regs(reg_alarm1, raw); !s) {
return std::unexpected(s.error());
}
date_time at{};
at.second = detail::from_bcd(raw[0] & 0x7f);
at.minute = detail::from_bcd(raw[1] & 0x7f);
at.hour = detail::hours_from_reg(raw[2] & 0x7f);
at.day = (raw[3] & 0x40) ? (raw[3] & 0x0f) : detail::from_bcd(raw[3] & 0x3f);
return at;
}
[[nodiscard]] static result<date_time> read_alarm2()
{
std::array<std::uint8_t, 3> raw;
if (auto s = dev::read_regs(reg_alarm2, raw); !s) {
return std::unexpected(s.error());
}
date_time at{};
at.minute = detail::from_bcd(raw[0] & 0x7f);
at.hour = detail::hours_from_reg(raw[1] & 0x7f);
at.day = (raw[2] & 0x40) ? (raw[2] & 0x0f) : detail::from_bcd(raw[2] & 0x3f);
return at;
}
[[nodiscard]] static result<bool> alarm1_fired()
{
return flag_set(a1f);
}
[[nodiscard]] static result<bool> alarm2_fired()
{
return flag_set(a2f);
}
[[nodiscard]] static status clear_alarm1()
{
return clear_flag(a1f);
}
[[nodiscard]] static status clear_alarm2()
{
return clear_flag(a2f);
}
// True after the oscillator was ever stopped (first power-up, battery
// ran out): the clock needs to be set.
[[nodiscard]] static result<bool> oscillator_stopped()
{
return flag_set(osf);
}
[[nodiscard]] static status clear_oscillator_stopped()
{
return clear_flag(osf);
}
// Die temperature in quarter C (updated every 64 s by the device).
[[nodiscard]] static result<std::int16_t> temperature_quarters()
{
std::array<std::uint8_t, 2> raw;
if (auto s = dev::read_regs(reg_temp, raw); !s) {
return std::unexpected(s.error());
}
return static_cast<std::int16_t>((static_cast<std::int16_t>(static_cast<std::int8_t>(raw[0])) << 2) |
(raw[1] >> 6));
}
// The alarms' INT/SQW wiring on its own, for a caller that arms once and
// mutes later. Alarm 1 and alarm 2 share INTCN, so muting one leaves the
// other's route intact.
[[nodiscard]] static status listen_alarm1()
{
return set_alarm_interrupt(a1ie, alarm_interrupt::on);
}
[[nodiscard]] static status mute_alarm1()
{
return set_alarm_interrupt(a1ie, alarm_interrupt::off);
}
[[nodiscard]] static status listen_alarm2()
{
return set_alarm_interrupt(a2ie, alarm_interrupt::on);
}
[[nodiscard]] static status mute_alarm2()
{
return set_alarm_interrupt(a2ie, alarm_interrupt::off);
}
private:
// Seconds, minutes and hours decode the same way wherever they are read
// from - the high bit of the first two is reserved, and the hours register
// carries its own 12/24-hour flag.
static constexpr time_of_day decode_time(std::span<const std::uint8_t> clock)
{
return {detail::hours_from_reg(clock[2]), detail::from_bcd(clock[1] & 0x7f), detail::from_bcd(clock[0] & 0x7f)};
}
static constexpr std::uint8_t day_date(std::uint8_t day, bool weekday_mode)
{
if (weekday_mode) {
return static_cast<std::uint8_t>(0x40 | (day & 0x0f));
}
return detail::to_bcd(day) & std::uint8_t{0x3f};
}
// INTCN routes the alarms to INT/SQW and BBSQW is the square wave that
// would otherwise drive it, so arming an alarm's interrupt takes the pin
// and muting it gives up only that alarm's claim on it.
static status set_alarm_interrupt(std::uint8_t enable_bit, alarm_interrupt interrupt)
{
auto control = dev::read_reg(reg_control);
if (!control) {
return std::unexpected(control.error());
}
const auto wired = static_cast<std::uint8_t>((*control & ~bbsqw) | intcn | enable_bit);
const auto muted = static_cast<std::uint8_t>(*control & ~enable_bit);
return dev::write_reg(reg_control, interrupt == alarm_interrupt::on ? wired : muted);
}
static result<bool> flag_set(std::uint8_t bit)
{
auto flags = dev::read_reg(reg_status);
if (!flags) {
return std::unexpected(flags.error());
}
return (*flags & bit) != 0;
}
static status clear_flag(std::uint8_t bit)
{
auto flags = dev::read_reg(reg_status);
if (!flags) {
return std::unexpected(flags.error());
}
return dev::write_reg(reg_status, static_cast<std::uint8_t>(*flags & ~bit));
}
};
} // namespace ds3231

1
libavr

Submodule libavr deleted from 1412b7173b

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@@ -1,9 +0,0 @@
libavr_format_test()
# The battery is a compile: a static_assert that fails is the failure. It is a
# target rather than only a ctest so a plain build catches a regression too.
add_library(consteval_tests OBJECT consteval.cpp)
target_link_libraries(consteval_tests PRIVATE ds3231)
add_test(NAME ds3231.consteval
COMMAND ${CMAKE_COMMAND} --build ${CMAKE_BINARY_DIR} --target consteval_tests)

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@@ -1,82 +0,0 @@
// Compile-only battery, built with the cross compiler so the target's 16-bit
// int is exercised. Everything in this driver that is arithmetic rather than a
// bus transaction lives here: the BCD both ways, the hours register's two
// formats, Sakamoto's weekday, and the alarm rate encodings as the datasheet
// tabulates them.
#include <cstdint>
#include <ds3231/ds3231.hpp>
namespace {
using ds3231::detail::from_bcd;
using ds3231::detail::hours_from_reg;
using ds3231::detail::to_bcd;
// BCD is a round trip over every value the registers hold, and the encoding is
// the datasheet's: tens in the high nibble, units in the low one.
consteval bool bcd_round_trips()
{
for (std::uint8_t value = 0; value < 100; ++value) {
const std::uint8_t packed = to_bcd(value);
if (from_bcd(packed) != value) {
return false;
}
if ((packed >> 4) != value / 10 || (packed & 0x0f) != value % 10) {
return false;
}
}
return true;
}
static_assert(bcd_round_trips());
// The hours register (19-5170 Table 1): bit 6 selects 12-hour mode and bit 5
// is then PM. Both noons and both midnights are the cases a naive decode gets
// wrong - 12 AM is hour 0 and 12 PM is hour 12, neither of which is 12 + 12.
static_assert(hours_from_reg(to_bcd(0)) == 0); // 24-hour midnight
static_assert(hours_from_reg(to_bcd(13)) == 13); // 24-hour afternoon
static_assert(hours_from_reg(to_bcd(23)) == 23);
static_assert(hours_from_reg(0x40 | to_bcd(12)) == 0); // 12 AM
static_assert(hours_from_reg(0x40 | 0x20 | to_bcd(12)) == 12); // 12 PM
static_assert(hours_from_reg(0x40 | to_bcd(1)) == 1); // 1 AM
static_assert(hours_from_reg(0x40 | 0x20 | to_bcd(1)) == 13); // 1 PM
static_assert(hours_from_reg(0x40 | 0x20 | to_bcd(11)) == 23); // 11 PM
// Sakamoto's method, against dates a calendar can be checked against rather
// than against this implementation run twice. Sunday is 1.
using ds3231::detail::weekday;
static_assert(weekday(2000, 1, 1) == 7); // Saturday
static_assert(weekday(2024, 1, 1) == 2); // Monday
static_assert(weekday(2024, 2, 29) == 5); // Thursday, the leap day
static_assert(weekday(2024, 3, 1) == 6); // Friday, the day after it
static_assert(weekday(2100, 3, 1) == 2); // Monday - 2100 is not a leap year
static_assert(weekday(2026, 8, 12) == 4); // Wednesday
// The alarm rate encodings (19-5170 Table 2), transcribed: the low bits are
// A1M4..A1M1 in register order and the high one is DY/DT. A rate is the mask
// pattern its row names, and a transcription slip here arms the wrong alarm.
using ds3231::alarm1_rate;
static_assert(static_cast<std::uint8_t>(alarm1_rate::once_per_second) == 0b01111);
static_assert(static_cast<std::uint8_t>(alarm1_rate::seconds_match) == 0b01110);
static_assert(static_cast<std::uint8_t>(alarm1_rate::minutes_seconds_match) == 0b01100);
static_assert(static_cast<std::uint8_t>(alarm1_rate::time_match) == 0b01000);
static_assert(static_cast<std::uint8_t>(alarm1_rate::date_time_match) == 0b00000);
static_assert(static_cast<std::uint8_t>(alarm1_rate::weekday_time_match) == 0b10000);
using ds3231::alarm2_rate;
static_assert(static_cast<std::uint8_t>(alarm2_rate::once_per_minute) == 0b0111);
static_assert(static_cast<std::uint8_t>(alarm2_rate::minutes_match) == 0b0110);
static_assert(static_cast<std::uint8_t>(alarm2_rate::time_match) == 0b0100);
static_assert(static_cast<std::uint8_t>(alarm2_rate::date_time_match) == 0b0000);
static_assert(static_cast<std::uint8_t>(alarm2_rate::weekday_time_match) == 0b1000);
// Alarm 2 has no seconds register, so its mask bits are one place lower than
// alarm 1's throughout - the property that makes one distribution loop wrong
// for the other.
static_assert(static_cast<std::uint8_t>(alarm2_rate::once_per_minute) ==
static_cast<std::uint8_t>(alarm1_rate::once_per_second) >> 1);
static_assert(static_cast<std::uint8_t>(alarm2_rate::weekday_time_match) ==
static_cast<std::uint8_t>(alarm1_rate::weekday_time_match) >> 1);
} // namespace