Well now. You need two serial ports on a pic that only has one hardware uart. I recently overcame this same problem by using a triple dual channel analog mux/demux (CD4053) between the pic and the max202E. The 202 already has two channels and the 4053 has 3 pairs of switches. I use them for Tx, Rx, and two LEDs. I use a pin on the pic as an output called com. select (CMSL) to toggle which serial port the UART is connected to. I will attach a schematic if the chip with pin discriptors. This works well if you always listen to one port and then after you get data you switch to another. Some ideas if this isn't possible would be to have a pic send data until it gets an ack from the master. Then the master could poll the different pics.
Gotta go.
Hope this helps.
Joe Kupcha
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