MSPM0C1106: How to enable the floating point printf(); function output with Keil

Dose customer can print fix-point value with no issue in Keil?

I not recommend to to printf(); in M0, it will take much of resources, memory and cpu load. Recommend to print the value by the UART directly.

Gary Gao said:

Dose customer can print fix-point value with no issue in Keil?

Correct.

I looked into other discussions, seems that MSPM0 serials can support the full spec stdio, and there is no issue to print the floating point data with L1306. so I'm curious about whether there is a build setting on this lib.

Gary Gao said:

I not recommend to to printf(); in M0, it will take much of resources,

It is required by customer debug routine, so need to use this function in development, but will block the function once device goes to mass production.

Thanks

Joe

Also not familiar such function with Keil, for CCS that is easy just to include the stdio.h and you can print it in the console. You can ask customer go to Keil's support form to get the expert there

Hi Gary

I test the printf() function in the C1106 project in ccs, seems there is some issue: 

If I add the printf() function as below, then click build, the console window will report a warning.

If i ignore the warning and start to debug the code, the project will stop at cinit function but not the first line of main function, then I click run the project will finally run into the main loop, but I cannot see anything printed in the console window.

but if I follow the warning move out the .cmd file manually as discussed in E2E thread, then add the -heap define, the project build will report issue.

even if I change the -heap size to 0x100 which is smaller than default, the same issue will also be reported.

Thanks

Joe

Hi Gary 

Thanks for your support, I use your demo can make printf work, but there are 2 questions:

If I change the variables from int to float, then the CIO output data is wrong.

Why the puts("") function is needed for the printf, seems there is no more description in the link you shared.

Thanks

Joe

I don't know about that, let me move this thread to CCS team to see if any comments there

I don't have a C1106, but on the L1306 I observed: (a) CIO takes just under 512 bytes of heap space (b) printf (the core function) takes well in excess of 256 bytes of stack space (I vaguely recall something like 350 bytes). The (software) floating point support probably adds (a small bit) to that.