However after 2~3 days running, the UART does not receive message.

Ick-Sung Choi

I am using OMEGA2+.

My program uses UART /dev/ttyS1 to communicate with other MCU.

It works when I start my program.

root@Omega-8E18:~/www1# dmesg | grep tty
[ 0.000000] Kernel command line: console=ttyS0,115200 rootfstype=squashfs,jffs2
[ 0.306640] console [ttyS0] disabled
[ 0.310075] 10000c00.uartlite: ttyS0 at MMIO 0x10000c00 (irq = 28, base_baud = 2500000) is a 16550A
[ 0.318850] console [ttyS0] enabled
[ 0.334538] 10000d00.uart1: ttyS1 at MMIO 0x10000d00 (irq = 29, base_baud = 2500000) is a 16550A
[ 0.344006] 10000e00.uart2: ttyS2 at MMIO 0x10000e00 (irq = 30, base_baud = 2500000) is a 16550A

How can I solve this problem?

It is very important job for me.

I will really appreciated if I can be given answer or suggestions.

Thank you very much.

JP Norair

I have also had trouble with the ttyS_ drivers.

There are some problems with the way flushing works, but you can try using tcflush() in your code to clear the system buffers. This can cause other problems, but it also might work for you.

Ick-Sung Choi

Dear JP norair.
Thank you very much for your precious answer.

William Scott

Additionally, messages not being received seems to bring up troubleshooting tip #1, that being, are messages being sent. Have you validated messages are still being sent after the stoppage of receipt?

--Bill

Ick-Sung Choi

Dear William Scott, Bill.

Thank you very much.

I am testing that messages are still being sent after the stoppage of receiptnow.

I made LED message receive/transmit checker at the other MCU.

Because this happens after 2~3 days from program running, It takes some time.

Thank you very much.

Ick-Sung Choi

Dear William Scott, Bill.

Thank you very much.

I can send the message after stoppage of receipt. The write function is executed normally.
Though read function is executed normally, my program can't receive any message.

I made LED message receive/transmit checker at the other MCU.

The MCU seems not to send/receive message.

This serial port hang happens after 2~3 days from program running.

Once this happens, the serial port does not work even though I re-run the program.

If I reboot or power down/up agin, the serial port works.

Thank you very much.