Hi!

I'm using AT89C52, and I'm trying
to connect it with max232 to PC serial port. I have managed to send byte from PC and receive it with uC. However when I send something back from uC i can't receive it on PC.
I have looked with oscilloscope and it looks like uC sends something out.

I'm using Linux 2.2.13 kernel, and by
looking at /proc/tty/driver/serial

0: uart:16550A port:3F8 irq:4 baud:9600 tx:9 rx:34 brk:13

tx and rx fields are changed when I run my program. tx is incremented by 1, I think that this is ok, since I send only 1 byte, and rx is incremented by 4.
I don't know why 4. ( I send 3 bytes from uC )

I have looked at Serial-Programming-HOWTO, and tried examples for Asynchronous input, but I can't catch SIGIO signal.

Can someone help me with this please, I'm kind of in hurry!

Thanks in advance.

-- Alen Kovac