I am doing a project that uses simple communications between a 51 and two other devices.

Device A uses a proprietary serial connection that keeps the 51 quite busy, device B is standard 8N1 19200 bps RS-232 -- the only problem is it has no flow control (hardware or software).

The protocol of device A is very timing sensitive; so much so that I have to keep the serial int disabled for rather long periods of time. Long packets of 50 bytes or greater are lost when the 51 is busy dealing with device A.

Are there 51's that have buffered UARTs, at least on receive? I could use an exeternal UART, but very limited on board space. This one byte SBUF is tiresome... ;)

Thanks for any suggestions!
Dan