A firmware for STC15L2K32S microcontroller on Black Board T5 ESP-13

Use SDCC to compile

Use STC MCU ISP flash tool to programm

Install both sdcc and stcgal per instructions (or use distribution packages for sdcc)

Programming the MCU is via a USB to serial converter connected to connector 3P, the BetaBlack MCU programming pins on /dev/ttyUSB0 Modbus communications is via the alternative pins connected to the ESP8266 via jumpers. These jumpers can be removed and a second USB to Serial converter used for testing via /dev/ttyUSB1. Refer here for MCU connection details.

cd blackboard-STC15
make
make install # will download to the MCU

Build the modbus-master program for testing communication

make modbus-master

Build ESP8266 code Use Arduino ESP8266 generic

• Open blackboard-ESP8266
• Edit SSID.h to suit your wifi network
• Remove the bridges between the WFI_GND, WFI_TX and WFI_RX
• Connect ESP8266 to USB-Serial converter to the WFI side (USB RX -> WFI_TX and vice versa)
• Bridge jumper WiFi_0 to enable ESP8266 programming mode
• Power on the BetaBlack
• Upload to the ESP8266
• Power off the BetaBlack
• Remove the USB serial and re-insert the bridges
• Power on the BetaBlack
• The ESP8266 will join your network and your DHCP will give it an address. You need to find the IP address it has joined as by looking at your router for address allocations
• curl http://your_ip_address (Gives the current register values)
• curl http://your_ip_address/status (Gives the modbus comms status)
• curl http://your_ip_address/relayon
• curl http://your_ip_address/relayoff
• curl http://your_ip_address/beepon
• curl http://your_ip_address/beepoff

What it supports for now:

• STC15 UART (baudrate: 115200)
• Reading on-board DHT11 values
• One-wire communications (DS18B20 temp sensor) via P1.5 (pin 4 of 5-pin header)
• I2C communications via pins 2 and 3 (SDA/SCL) of 5-pin header (tested with BH1750 light sensor)
• Using PWM to flash on-board RGB LEDs
• On-board beeper
• On-board relay
• Second uart for communicating with the ESP8266
• MCU Modbus client communication to read/write some of the peripherals based on https://github.com/angeloc/simplemodbusng
• Linux modbus-master test program based on libmodbus for bypassing the ESP8266
• Implement a timer to power off the ESP8266 by the STC15
• Implement modbus master in ESP8266 for read state of MCU peripherals
• Implement writes to the beeper and relay over http

TODO

• Control the LEDs via http