2_ Board description

On the picture below is the description of the pins and components of this little beauty. When i first look at this board i was thinking, that will be an easy start. But i was very wrong. There is no documentation for this board at all. I then i found this picture. It's not much, but shows the basics. On the borders of this board are the pins marked as A015, B015, C0~3 and these are pins of port A, port B and port C. The four SWD pins are used for programmers/debugers like st-link, j-link... There are also a boot jumpers, which are very important because we need them to program the chip. If we want to program the chip we must put the pin that is far from reset button(that one which is closer to B11 and B10 port) to 1.

If you want to program this chip you can use an USB to TTL converter. I recommend one, like this on the picture below, because it has a lot of other signals, which may be beneficial in the future. For now i am using the one with CH340G chip on it and it works perfectly.

How to program the chip with this usb to ttl adapter i will describe in details later on this wiki. But only for remark, that we will use usart1 port on chip.

USB2TTL         STM32F103C8T6
3V3 ----------- 3,3
GND ----------- G
TXD ----------- PA10 (RX)
RXD ----------- PA09 (TX)

This configuration is tested and works with no problems. You can also use usart2 and usart3 port for this, but i wasn't tested them.

usart2: PA02 (TX); PA03 (RX)
usart3: PB10 (TX); PB11 (RX)