On Wed, Oct 03, 2001 at 01:13:13PM +0200, Wojciech Zabolotny wrote:
> Hi All,
>
> I have to use PC to communicate with RS-485 bus. I'd like to use the 9-bit
> addressing codes available for PICs/8051s and other uCons. Unfortunately
> The PC's UART is 8-bit, but I can manually control the parity bit.

Woj,

You need to read a bit more! ;-) PIC's do nine bits. Take a look at page 103
in section 10.2.3 in the 16F877 manual. It describes not only the ninth bit
but more importantly how to configure the USART interrupt so that it'll only
interrupt when the 9th bit is set.


> Probably there is no problem with sending - I can change the parity mode
> to get the proper 9th bit.

No need. See the last paragraph on page 99.

[ Other possibilities truncated... ]

There's no need to do anything exotic. The PIC USART handles 9 bits just
the way you would expect it to...

BAJ

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