Posted on May 17, 2011 at 13:45I had tried the previously posted USART1 code fragment on an STM32F103RET device (512KB), there wasn't any other initialization of hardware from the boot vector to the main() function. So I'm pretty sure it represents the minimal requirements to actually get the USART to function.
Are you sure the code is actually downloaded and running? Can you step it along with a JTAG debugger? In Keil you can actually view the peripheral and clock settings.
The USART1 output pin shouldn't be floating. As you have wires to the Rx pin PA.10 you could try setting it as a PP GPIO output and bang it up and down to see if that is working in the loop. You could try something similar on PA.9 too. Do you have any other pins connected to LEDs or other signs-of-life type indicators which you could toggle?
You could perhaps try the code on an eval/dev board with the pins already wired to an RS232 interface.
-Clive
Edit: Not sufficiently familiar with IAR, but you might want to check the RAM and STACK settings for the project, or code in the startup.s (or whatever) that takes the boot vector/initial stack pointer. If something is wrong there the CPU will Hard Fault. You could evaluate this by debugging with a JTAG probe and walking through the code as it executes.
