[RPMSG error] No memory for tty_prepare_flip_string

[OBaselga]

Hi everyone,

I'm coding an applicaction which needs to send data from CM4 to CA7 through RPMSG framework. FreeRTOS task involved:

void t0Task(void *argument)
{
  int count = 0x0, sim_ch = 9;
  const int SIZE_DATA = 7;
  unsigned char msg[SIZE_DATA * sim_ch], msg2[SIZE_DATA];
  TickType_t xLastWakeTime;
  const TickType_t xFrequency = 1;
 
  while (1)
  {
	  xLastWakeTime = xTaskGetTickCount();
 
	  msg[0] = '\0';
	  int i;
	  for (i = 0; i < sim_ch; i++) {
		  sprintf(msg2, "%06X", count);
		  strcat(msg, msg2);
		  strcat(msg, " ");
		  count = (count + 1) % 0xFFFFFF;
	  }
 
	  VIRT_UART_Transmit(&virtUART0, (uint8_t*)msg, strlen(msg));
	  vTaskDelayUntil( &xLastWakeTime, xFrequency );
  }
}

I need to achieve a throughput near 1.5 MB/s - for that, "sim_ch" variable should be 128.

When this firmware is executing, an error appears after few seconds: "rpmsg_tty virtio0.rpmsg-tty-channel.-1.0: No memory for tty_prepare_flip_string". How can I solve it?

Thanks,

Oscar

[PatrickF]

Hi,

at first look, msg size defintion is missing one position to store the '\0' at the end of the string, so in your example msg real length in memory is sim_ch*7+1

maybe try:

unsigned char msg[ (SIZE_DATA * sim_ch) + 1], msg2[SIZE_DATA];

See also this (old) message https://community.st.com/s/question/0D50X0000BNugJi/no-memory-for-ttyprepareflipstring

and on wiki

https://wiki.st.com/stm32mpu/wiki/How_to_exchange_data_buffers_with_the_coprocessor

Regards.