I would like to implement an RS485 Link master using STM32L053 that only receives words when it is woken up by hardware address matching (9 bit data with msb set for address marker). On the face of it the Multiprocessor mode allows the address wake up, but that appears to remove access to the DE pin feature.
Is it possible to have both enabled? Or do I have to implement DE manually?
I've tried starting from and RS485 port and enabling address wake up, and the opposite; starting from multiprocessor and enabling DE Driver Enable. Both failed.
if (HAL_MultiProcessor_Init(&huart1, 1, UART_WAKEUPMETHOD_ADDRESSMARK) != HAL_OK)
{
Error_Handler();
}
if (HAL_RS485Ex_Init(&huart1, UART_DE_POLARITY_HIGH, 0, 0) != HAL_OK)
{
Error_Handler();
}
Even though the code appears to do 'something' The DE pin can't be configured as DE because the UART is in the wrong mode. I think I'm onto a lost cause, and the best route is probably to give up and enable/disable the drivers using software?
