Re: 9 bit communication on RS 232

suchitra wrote:
> Hello All
> I wanted to know how can we configure com port for 9 bit
> communication.
> I intend to use the 9th bit as Address/data bit..since i want to
> communicate with more than one devices.
> I am using turbo c compailer if some one can give me some reference
> code that will be great..
> with kind Regards
> Suchitra

It is perfectly possible but difficult to produce 9-bit data on a standard
PC UART.  However, as noted by other posters 9-bit mode is almost a standard
for microcontrollers, using the 9th bit as an address flag.

Several posters have noted the possibility of forcing a 1 or 0 in the parity
bit which is the only way of achieving what you want.  In DOS it is
moderately easy to achieve this.  In Windows almost impossible.

However, there are ready written libraries and device drivers available eg.
Comm-Drv from http://www.wcscnet.com/Software.htm