How many optical encoders are we allowed to use on the robot this year?
Well, it depends, i believe it is limitless. The only snag you may have is the number of C-Rio Cards you have and sidecars you have. Other than that i believe those are the only limits… we have left over digital inputs on our sidecar and on the C-Rio itself… We’re using 4 encoders, the linetrackers, an optical sensor, and the compressor… how many do you plan to use?
Do you mean how many encoders are we using or compressors?
how many encoders you want to use
You are actually limited to 12 in hardware. Why? The FPGA can only handle 8 Counters and 4 Encoders. the Encoder library uses Encoders for 4x decoding (meaning you can use up to (4) 4x-decoded encoders) and Counters for 1x or 2x decoding (meaning you can have up to (8) 1x or 2x-decoded encoders). 4+8=12, so 12 encoders max.
This assumes that each encoder is either quadrature or otherwise uses the FPGA Counters (such as a gear tooth sensor).
If you need more than 12, your best bet would probably be to use a co-processor to handle the inputs and either feed them to the cRio via SPI, I2C, Serial, or DACs.
You’re limited to 41 jaguars by cost, but each jaguar can read a single encoder using CAN.