If you don't want to lose data then here's the options...

1. Have a handshake protocol, (either embedded in software such as XON/XOFF) or in Hardware (such as RTS/CTS) etc. They were invented so that your tetraplegic Cray Supercomputer would not lose data being sent to it from your Golfball teletypewriter. Most folks don't bother with these any more (or have forgotten what they were invented for)... and then when they lose data or discover it's corrupt they cry into their coffee posting messages that it's all diluted and undrinkable.

2. Ensure the data being received is at a SLOWER speed than the data being transmitted. This has a neat side-effect of saving on having to buffer in the middle.

3. Ensure that the speed of your PIC is adequate to handle the dataprocessing involved. This usually means you can't run your PIC on a 32kHz watch crystal.

4. Ensure you have a sufficient data buffer in the middle to handle unexpected situations. Some folks have tried to do this with a 12C509 and wonder why they can't define a 512Mb RAM buffer (probably because they're using an old version of PBP).

You may need to implement some, any or all of the above.

Melanie