Re: [libopencm3-devel] Request: USART TX/RX busy status

[<ka...@as...>]

Warren Gay:
...
> inline static int
> usart_tx_ready(uint32_t usart) {
>     return (USART_SR(usart) & USART_SR_TXE) != 0;
> }
> 
> static void
> uart_task(void *args) {
>     char ch;
> 
>     for (;;) {
>         /* Receive char to be TX */
>         if ( xQueueReceive(uart_txq,&ch,500) == pdPASS ) {
>             while ( !usart_tx_ready(USART1) )
>                 taskYIELD(); /* Yield CPU to ready tasks */
>             usart_send_blocking(USART1,ch); /* blocking call */
>         }
>     }
> }

 This is how I'm doing it:
http://aspodata.se/git/openhw/libarm/tty_fd_run.c

...
> So it would be a welcome addition to the libopencm3 library to provide
> routines:
> 
>     int usart_send_ready(uint32_t usart);
>     int usart_recv_ready(uint32_t usart);

Why not http://aspodata.se/git/openhw/libarm/stm32/tty_ll.h

 I use the above as in:
http://aspodata.se/git/openhw/regulator/regulator.c

it is strictly polled, even gives me simple command line editing.

Regards,
/Karl Hammar

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