Serial communication advice for several pics?

[joeh100]

Hi, I'll be using a 4550 to control 2 motors, 2 servos, decode 2 quadrature position encoders, communicate with an LCD and communicate with a pc via usb. I'm actually doing all of this right now with just the 4550 (not the usb yet). I've obviously hit a bottleneck decoding the position encoders which forces me to keep the motor speed slow.

I'll be handing off the encoder work and LCD communication to 2 other PIC's. I don't really have a lot of experience with serial communications, so I'm not sure where to start looking? The question is what method to use to communicate between the different pic's and allow for expansion later if I need to. More specifically I guess, is how to communicate with several pics on the same bus. What protocol? I still need to keep the usb open on the 4550 also.

Thanks,

Joe

 

[blueroomelectronics]

Fast SPI
Short range multi master I2C
Long range RS485

 

[joeh100]

Thanks, I'll do a little research on SPI and I2C. It's not long range.