Custom STM32F103C8T6

Dallasta Fri May 20, 2016 7:06 pm

Hey guys!

I recently designed a custom STM32 board for an RS485 aplication. I was using an Atmega 168 before and I was having trouble with speed, so I decided it was time to move.
The board is simply a STM32F103C8T6 with an AS5048A magnetic encoder and a SN65HVD78 transceiver. It reads the encoder via SPI and sends the information to a dynamixel servo network, using the dynamixel protocol. I have the SWD pins to program it.
As I already have the code for the arduino IDE so I was thinking what should I modify on my code to port it. Another question I have is how I set the clock on the microcontroller (on AVR devices you use the memory fuses)? I’m using a 16Mhz crystal to reach the 72Mhz.
If you want, I can send the codes, the libs and the board schematic.
Here is a picture of the boards (I have two different models to fit in different places). I’m now soldering them and waiting for a few components to arrive.
Image
I would apreciate a lot if someone could help me here.
Thanks!

Replies

RogerClark Mon Sep 26, 2016 10:54 pm

I suspect the STLink V2.1 would fit in a C8, especially as most C8’s are really CB’s ;-)

But I think the point is that the STLink (even V2) is not intended as a bootloader its a debugger, and would severely limit the amount of available code space left for applications.

The BMP is pretty much the same as the STLink, except without mass storage, and the BMP is quite large as well (i.e it would not be useful as a bootloader)

I think a mass storage bootloader would be great to have, but as using the HAL etc or any other lib e.g. libopencm3 would be impractical due to size, I doubt its practical

octavio Wed Aug 30, 2017 7:19 pm

Is the external 8Mhz and 32khz crystals required or it could work (arduino bootloader and libs) just with the internal rc?
usb is not used.

Pito Wed Aug 30, 2017 8:54 pm

usb is not usedIt could work when the RC oscillator’s frequency is known with at least 1-2% precision – because of Serial UART and of course millis() and friends.
STM32duino bootloader is usb based, but you may use ST-LINK/J-LINK, or serial upload.