Firmware replacement for STC15F mcu-based DIY Clock Kit (available from banggood [see below for link], aliexpress, et al.) Uses sdcc to build and stcgal to flash firmware on to STC15F204EA (and STC15W408AS) series microcontroller.
link to Banggood product page for SKU 972289
- time display/set (12/24 hour modes)
- date display/set (with reversible MM/YY, YY/MM display)
- day of week
- year
- seconds display/reset
- display auto-dim
- temperature display in C or F (with user-defined offset adjustment)
- alarm with snooze
- hourly chime
- time sync to GPS receiver outputting serial NMEA data
- on
gpsbranch: https://github.com/zerog2k/stc_diyclock/tree/gps - for STC15W408AS or STC15W404AS (sorry no STC15F204EA, not enough ram/code, no hw uart)
- very experimental at this point (help wanted to polish this)
- on
note this project in development and a work-in-progress Pull requests are welcome.
- time sync to WWVB radio receiver module (for STC15W408AS)
- DIY LED Clock kit, based on STC15F204EA and DS1302, e.g. Banggood SKU 972289
- connected to PC via cheap USB-UART adapter, e.g. CP2102, CH340G. Banggood: CP2102 USB-UART adapter
| 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.
choose platformio (preferred) or traditional make build
- assumes you have platformio installed
- choose which mcu you are building for by uncommenting one
env_defaultinplatformio.ini - adjust
upload_portas needed inplatformio.ini
make clean
make
make flash
-
override default serial port:
STCGALPORT=/dev/ttyUSB0 make flash -
add other options:
STCGALOPTS="-l 9600 -b 9600" make flash -
flashing STC15W408AS:
STCGALPROT="stc15" make flash
If you like, you can try pre-compiled binaries here: https://github.com/zerog2k/stc_diyclock/releases
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
new firmware operation flow diagram
original firmware operation flow state diagram
Kit instructions w/ schematic: scan | PDF
