AM625: M4 Custom Baud Rate

Hello John,

Vaibhav Kumar said:

As a part of the next step, I will try to test your settings on the AM62x EVM and see if the 1.33 MHz baud rate is achievable if I hard code the settings in the SysConfig runtime generated files.

I tried this and 13x baud rate gives a divisor value of 11.

So the effective baud rate becomes = 1342657 with 192 MHz clock frequency.

UPDATE I did custom driver changes and made your use case WORK!! 

I was able to make the settings clock = 192 MHz, baud rate = 1333333 and operational mode = 16x work.

The divisor value = 9 at line 1062, hence this is achievable. 

The steps to achieve this would be as follows:

1. In SysConfig initially set 13x itself and build the application.
   
   
   
2. Once the application is build, then go ahead and copy the generated sysconfig files to the project directory. So you would need to copy only the .c and the .h files from C:\Users\A0502407\workspace_v12\uart_echo_am62x-sk_m4fss0-0_nortos_ti-arm-clang\Debug\syscfg  to the directory C:\Users\A0502407\workspace_v12\uart_echo_am62x-sk_m4fss0-0_nortos_ti-arm-clang
   
   
3. Once this is done, go back to CCS window and then click on the SysConfig icon and set it as exclude from build
   
   
   
4. Now I would need you to make changes in the following files:
   1. ti_drivers_config.c
      
      
      
   2.  ti_drivers_open_close.c
      
5. Now that this is done, simply go ahead and rebuild the application from CCS itself.
6. Once done, put a breakpoint in the file uart_v0.c and in the API UART_configInstance() at the highlighted line
   
   
   
7. Once the divisor value is computed you will see that it turns out to be 9.

If this helps you out please mark the thread resolved.

Regards,

Vaibhav