Firmware replacement for STC15 MCU-based DIY Clock Kit available on banggood, aliexpress, etc. Uses sdcc to build and stcgal to flash firmware on to STC15W408AS series microcontroller.
This repo is forked from https://github.com/zerog2k/stc_diyclock, which has been archived.
- zerog2k - for the alternative STC DIY Clock firmware and for maintaining the original repo for 6 years
- venustrg - for implementing synchronization with NMEA devices
There are multiple revisions/versions of this DIY kit. The version I have is based on the
STC15W408ASmicrocontroller, it doesn't have the 3rd button and the music chip (the documentation is here: 1, 2).I made some changes both in hardware and firmware (6 digit (HH:MM:SS) version) and I only tested them with the kit version mentioned above. If your version is different from mine, please consider using the original repo instead.
- Updated ESP8266 script for NTP synchronization
- Improved documentation
- Major refactoring, improved code quality and readability, reduced firmware size
- Fixed a bug in the NMEA crc calculation logic
- Added an inactivity timer - the clock will go into normal mode from any screen if no buttons are pressed for 10 seconds
- Added support for the 6-digit (HH:MM:SS) version
- Updated documentation
- The firmware was tested for both 4-digit and 6-digit version
- Improved auto-dimming logic
- Fixed compilation errors and improved code style
- Some changes in screens and button functions (according to my personal preferences)
| Name | Enabled by default | Constant(s) in code |
|---|---|---|
| Time display/set | N/A | N/A |
| Seconds display/reset | N/A | N/A |
| Automatic display dimming | N/A | N/A |
| 12/24 hour modes | Yes | WITHOUT_H12_24_SWITCH |
| Date display/set (MM/YY or YY/MM) | Yes | WITHOUT_DATE |
| Day of week | Yes | WITHOUT_WEEKDAY, AUTO_SHOW_WEEKDAY |
| Year | Yes | WITHOUT_DATE, AUTO_SHOW_DATE |
| Temperature display in C or F (with user-defined offset adjustment) | Yes | AUTO_SHOW_TEMPERATURE |
| Alarm with snooze | Yes | WITHOUT_ALARM |
| Hourly chime | Yes | WITHOUT_CHIME |
| Time synchronization via GPS or NTP protocol | No | WITH_NMEA, WITH_NMEA_DEVICE_SWITCH |
| 6 digit (HH:MM:SS) version support | No | SIX_DIGITS |
| Inactivity timer | Yes | WITHOUT_INACTIVITY_TIMER |
Most features can be enabled or disabled using the corresponding compilation constants.
- DIY LED Clock kit, based on
STC15W408ASandDS1302 - Connected to PC via cheap USB-UART adapter, e.g. CP2102, CH340G
| P1 header | UART adapter |
|---|---|
| P3.1 | RXD |
| P3.0 | TXD |
| GND | GND |
| 5V | 5V |
- linux or mac (windows untested, but should work)
- sdcc installed and in the path (recommend sdcc >= 3.5.0)
- stcgal (or optionally stc-isp). Note you can either do
git clone --recursive ...when you check this repo out, or dogit submodule update --init --recursivein order to fetch stcgal.
make clean
make
make flash
When calling
makewithout arguments, the firmware is built for the 4-digit version and without NMEA support.
Other options:
- 6-digit version with NMEA support
make GREEN6=1 NMEA=1
- 6-digit version without NMEA support
make GREEN6=1 NMEA=0
- 4-digit version with NMEA support
make GREEN4=1 NMEA=1
-
serial port:
STCGALPORT=/dev/ttyUSB0 -
other options:
STCGALOPTS="-l 9600 -b 9600" -
flashing STC15W408AS:
STCGALPROT="stc15"
Instead of stcgal, you could alternatively use the official stc-isp tool, e.g stc-isp-15xx-v6.85I.exe, to flash. A windows app, but also works fine for me under mac and linux with wine.
note due to optimizations that make use of "eeprom" section for holding lookup tables, if you are using 4k flash model mcu AND if using stc-isp tool, you must flash main.hex (as code file) and eeprom.hex (as eeprom file). (Ignore stc-isp warning about exceeding space when loading code file.) (not really needed anymore as current build is within 4k code)
To generate eeprom.hex, run:
make eeprom
For STC15F204EA, some of the code assumes 11.0592 MHz internal RC system clock (set by stc-isp or stcgal). For example, delay routines might need to be adjusted if this is different. (Most timing has been moved to hardware timers.)
This code is provided as-is, with NO guarantees or liabilities. As the original firmware loaded on an STC MCU cannot be downloaded or backed up, it cannot be restored. If you are not comfortable with experimenting, I suggest obtaining another blank STC MCU and using this to test, so that you can move back to original firmware, if desired.
http://www.stcmcu.com (mostly in Chinese)
stc15f204ea english datasheet: http://www.stcmcu.com/datasheet/stc/stc-ad-pdf/stc15f204ea-series-english.pdf
stc15w408as english datasheet: http://www.stcmicro.com/datasheet/STC15F2K60S2-en2.pdf
sdcc user guide: http://sdcc.sourceforge.net/doc/sdccman.pdf
some examples with NRF24L01+ board: http://jjmz.free.fr/?tag=stc15l204
Maxim DS1302 datasheet: http://datasheets.maximintegrated.com/en/ds/DS1302.pdf
VE3LNY's adaptation of this hardware to AVR (he has some interesting AVR projects there): http://www.qsl.net/v/ve3lny/travel_clock.html