RTOS/TM4C1294KCPDT: System_printf() causing CAN receive messages to miss

Abhijit Acharekar

Part Number: TM4C1294KCPDT

Tool/software: TI-RTOS

Hello,

I have read another thread where System_printf() interfering UART messages.So this should be similar but what happens exactly that would like to know (what cause even can_rx_isr not to hit?).

I am evaluating a CANOpen stack and therefore added quite some System_printf() and System_flushI() calls in my code.

Thanks & Regards

Abhijit

over 6 years ago

0 Bob Crosby over 6 years ago

TI__Guru 72500 points

The default for System_printf() is to set a breakpoint that is hit when a buffer is to be flushed. The CPU is stopped while the buffer is read by JTAG. This is very disruptive to a real time environment. (The CAN messages keep coming but the CPU has stopped.) Do you have access to a UART that could be used to print your system messages to a terminal emulator? Use UARTprintf() which is defined in C:\ti\TivaWare_C_Series-2.1.4.178\utils\uartstdio.c. Also define "UART_BUFFERED" in your project to avoid stalling the CPU on UART reads or writes.

0 Abhijit Acharekar over 6 years ago in reply to Bob Crosby

Intellectual 640 points

Hi Bob,
Thank you for your reply and suggestion.
Is it true if this System_printf-breakpoint scenario happens only during debugging mode? what happens to System_printf in release mode?
Thanks & Regards
Abhijit

0 Bob Crosby over 6 years ago in reply to Abhijit Acharekar

TI__Guru 72500 points

There is no difference in the System_printf implementation in the default implementation of the Debug and Release configurations. Here is some more information about System_printf()
processors.wiki.ti.com/.../Tips_for_using_printf

0 Bob Crosby over 6 years ago in reply to Abhijit Acharekar

TI__Guru 72500 points

You can disable the halting of the CPU by clearing the "Enable CIO function" check box. But of course the System_printf() function will no longer work.

0 Abhijit Acharekar over 6 years ago in reply to Bob Crosby

Intellectual 640 points

.Thank you for all your responses, Bob.

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RTOS/TM4C1294KCPDT: System_printf() causing CAN receive messages to miss