Talon SRX encoder cable max length

#21

For anyone interested in purchasing these boards, they are currently on pre-order. I should hopefully be receiving an advance batch of production units in the beginning of next week and stock is limited. You can order online now to reserve yours, here: https://rmrf.store/product/encoder-extender

0 Likes

#22

Is that for 2 or 1 unit(s)?

0 Likes

#23

This is for an encode/decode pair

0 Likes

#24

Living next to team 195 (and hence Rob) we were fortunate enough to receive a beta pair of the differential encoder signal converters.

We’ve successful used one on a fairly short (~2.5ft) run between a bank of 6 neos fed into a motion magic setup on our talons using the quadrature signal from a ctre mag encoder without issue.

Today we also connected part of our gatherer that uses the absolute feature (PWM instead of quadrature) of the ctre mag encoder on a run over 10 ft long without any issue so far.

Early oscilloscope testing shows no loss in the signal waveform on either the quadrature or PWM inputs and we haven’t had any power issues yet. More to come.

0 Likes

#25

Your mag encoder wire to cat6 is a fantastic idea we would have loved to use this last year.

0 Likes

#26

AFAIK, the mag encoder runs of 3.3V, so if it went out and lost counts, so would the microcontroller onboard the Talon. Certainly you’d get a fault before then. Unlikely, but maybe a high-resistance cable (bad crimp) going to the mag encoder would do it. That being said I assume the first thing you did was swap the cable.

0 Likes

#27

Weirdly enough, we saw this error on multiple robots. Perhaps we wired them all incorrectly, but I doubt it, since it was just a short ribbon run.

0 Likes

#28

Question realted to this topic. Looking around CD it appears that teams that make their own SRX encoder cables are using this 30AWG wire from Digi-Key:

https://www.digikey.com/product-detail/en/3m/3756-10-100/ME10G-100-ND/3867658

How does this work with R60:

Do you think the phrase “Wires that are recommended by the device manufacturer…” cover the use of 30AWG in this case?

0 Likes

#29

I wonder if you could use these for the encoders:


0 Likes

#30

We ended up using these for some of our longer encoder cables (I think one was something crazy like 11 feet) and shielded CAT6a cable. It was kind of annoying to make the cables, but they work well and I doubt we’d get a clean signal without them. Looks like the SparkFun board is similar to the Adafruit one in functionality, and if someone combined them it would make a simple data cable to RJ-45 adapter that I imagine would make the process a lot simpler.

0 Likes

#31

Is there a specific kind of CAT6 cable suggested to be used with these boards? Is crimping our own CAT6 cables not recommended?

We bought one yesterday after having smoked out 2 arm motors this past weekend due to a 9ft ribbon cable run to a Mag Encoder on our wrist. It was impossible to replicate the issue on the practice field or our pits but can be seen here at the 30 second mark. This issue killed us all regional long and was the reason we didn’t compete in eliminations. Hopefully it will arrive before our next competition on April 4th.

0 Likes

#32

Your boards shipped out today. Any cat6 cable should work fine. TIA568B pinout is recommended if making your own, but we recommend using a cable pre-manufactured and tested to the cat6 standard.

0 Likes