UART not working

[scancool]

I have the iMX233-OLinuXino-MICRO, when I put the sdcard and power up the board, after a few seconds the green led comes up, I have also connected serial interface to putty with a baud rate of 115200, but there is no data coming from the board, the usb to serial is working I had tested, what could be wrong?

[euromatic]

The UART has TTL level and a regular serial interface would not work.
You must build(see MAX232) or buy an adapter.