[En-Nut-Discussion] detecting UART parity errors

[Trevor O'Grady]

>However, I'd prefer to fix parity error handling in the new driver.
>No question, I'd welcome if you add (and test) the required
>modifications, send it to me and I'll commit it. :-)

Hi Harold,
Here is the modified RxComplete function (uartavr.c) that discards bytes
received with parity error. Sorry it took so long but I struggled with
building the OS until I changed from ICC to winavr.
I have tested all combinations ( parity = none, odd and even )and it works.
I have tested this on a mega128 (Ethernut 1.3F). There was no define for
USR1 so I had to use UCSR1A.

static void RxComplete(void *arg)
{
    NUTDEVICE *dev = (NUTDEVICE *) arg;
    IFSTREAM *ifs = dev->dev_icb;
    UARTDCB *dcb;
    u_char par;

#ifdef UDR1
    if (dev->dev_base)
	{
        par = inp (UCSR1A) & 0x04; //parity error if UCSRnA bit 2 is set
        ifs->if_rx_buf[ifs->if_rx_idx] = inp(UDR1);
	}
    else
#endif
	{
        par = inp (USR) & 0x04; //parity error if UCSRnA bit 2 is set
        ifs->if_rx_buf[ifs->if_rx_idx] = inp(UDR);
	}

	if(!par) {
		if (ifs->if_rd_idx == ifs->if_rx_idx++) {
			dcb = dev->dev_dcb;
			NutEventPostAsync(&dcb->dcb_rx_rdy);
		}
	}
}

Regards and happy new year,
Trevor