I am trying to Interface a serial Communication device (which we developed ) to an EPABX through Serial Port. The EPABX has the Communication Parameters as 1200 baud, 7 Data BIts 1 stop bits , No Parity.

In the serial Communication Device, I am using a 89c52(Atmel) controller with Max232 Serial Interface IC. I am able to set the above parameters with 8 data bits,( mode 2) but there seems to be no way to set 7 databits.

Can anybody suggest how to configure a serial port for 7 data bits