Encoder Compatibility

[AccioTardis221]

Our team has been trying to set up some encoders and the instructions say that it connect should connect to the Talon motor controller, but we were trying to use Victor sp controllers. Are the Victor sp controllers compatible with the encoders from the kit of parts, or do we need to switch?

[adciv]

Which encoders are you using? Please give the part number or a picture. It sounds like you're trying to use the new one from CTRE but I think only one came with the KOP and you're saying you have more than one.

[AccioTardis221]

It's a CTRE encoder from the KOP. I believe we just bought more of them so we have multiple encoders.

[adciv]

Ok, this gets a bit more interesting. Short version, not compatible. But you MIGHT still be able to use them. Long version as follows.

The Talon SRX motor controllers are designed to be able to read sensors directly on their input port. The CTRE Encoders you have are designed to be plugged directly into the Talon SRX motor controllers (cable is provided in each box. The Victor SP motor controllers cannot take sensor input directly.

If you want to use these without using a Talon SRX, you would have to connect these to the roboRIO (not trivial, and need to check voltage requirements) and read the data through there to command your Victor SP motor controllers.

If you have the budget, I'd recommend switching to the Talon SRx. Just make sure you're using the Talon SRX in CAN mode, not PWM.

[ozrien]

So you have a few options...

[1] If you haven't already, leverage the free VEX voucher for 2 Talon SRXs. If you choose Talons you will get 2 for FREE. This also means leveraging the closed-loop features of the Talon since the Talon directly supports this sensor (absolute and relative). You can also read the sensor data from the roboRIO over CAN Bus since the Talon forwards everything to the RIO.
http://www.vexrobotics.com/pdv-2016.html

[2] You can use a CTRE Quadrature breakout in reverse.
http://www.ctr-electronics.com/talon...out-board.html
Normally this is used to connect a quad encoder's QuadA/B/Power/Ground to a Talon, but it can be used this way...
Mag encoder ----- ribbon cable--- breakout --- solder wires to the roboRIO.
Just wire QuadA, QuadB, 5V, and ground as you normally would on the RIO side.
The Mag encoder needs 5V, which you can get from a VRM or from the roboRIO.

[3] Using this breakout and solder wires.
http://www.ctr-electronics.com/breakoutmodule.html
The Talon SRX User's Guide and Mag Encoder User's Guide has pinout information for quadrature and power (below).

Also wiring the Magnetic Encoder to the roboRIO means you lose the ability to track the absolute position (within one rotation). In other words, you are only measuring the quadrature interface of the sensor. But as explained in Mag Encoder's User's Guide - section 5.3 - first paragraph - you can use the sensor as a simple 1024CPR encoder on anything that can decode quadrature, including the RIO.

Section 1.3 in the Mag Encoder's User's Guide has the pinout on the magencoder side.
Section 1.4.3 in the Talon's SRX User's Guide also has pinout wiring for a quadrature sensor. This is effectively the pinout you are looking for (QuadA,QuadB,5V and ground are the same pins on both sides of the ribbon cable). Make sense?

If you want to use the limit switch contacts on the Mag encoder, consider also wiring out pins 4/8 for the forward/reverse limit switches.

Look at section 1.4.1 in the Talon's User's Guide to check the connector's orientation to pin1 (ribbon connector is keyed the same on the breakouts so it's helpful).