STM8S005C6T6 Ethernet development board

In this project, we built an STM8S005C6T6 based Ethernet development board for our IoT experiments. This development board consists of ENC28J60, 10BASE-T stand-alone Ethernet controller, CH340G, USB serial interface, 2 LED indicators, and passive buzzer unit.

The firmware framework for this development board has been developed using SDCC. To enable IPv4 support, we convert the EtherCard driver, which is available for the Arduino platform. The current version of this driver supports all other EtherCard functions except TCP support.

Finished STM8S005C6T6 IoT development board.

In the given design, the SPI terminals of the MCU are connected to the ENC28J60 Ethernet controller. All SPI terminals, such as MISO / PC7, MOSI / PC6, and SCK / PC5, are connected directly to the Ethernet controller. In addition, the PC4 terminal of the MCU is used as ENC28J60, CHIP-SELECT.

The CH340G USB serial interface is connected to the UART2 terminals of the MCU. In STM8S005C6T6, the UART2 is mapped to the PD6 and PD5 terminals of the MCU. The USB interface of this development board consists of the jack-sense feature. The jack-sense status can access from PD7.

The minor peripherals such as LED indicators and buzzer are connected to the PORTD of the MCU. The LED indicators are connected to terminals PD0 and PD1 and can be activated or deactivated via jumpers. The passive buzzer is connected to PD4 and can run through the STM8 beep sound generator unit.

All peripherals of this development board are powered by a 3.3V supply. The recommended supply voltage for this development board is 5V to 9V.

Bottom view of the STM8S005C6T6 IoT development board.

In addition to the STM8S005C6T6, this development board supports the following STM8 series, LQFP48 packaged microcontrollers: STM8S007C8T6, STM8S207C8T6, and STM8S105C6T6.

All the resources of this development board are available at the GitHub project repository. The supplied firmware is developed and tested with SDCC version 3.8 on a Linux environment. Before compiling and flashing the MCU, make sure to install the stm8flash application on the system. The supplied makefile use this application to program the fuses and flash memory of the MCU.

The schematic and PCB design of this project is released under the terms of CERN-OHL-W Version 2.0. The firmware framework is released under the terms of the GNU GPL 2.0 license.

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