Signal specs for FIRST contorllers

Technical Technical Discussion
1

I’m looking for signal specifications for FIRST controllers. Here is what I am looking for:

  1. pinout for Spike BLUE relay control (blk, red, wht) and how to drive them from a BS2 for a hobby project.

  2. PWM specs for Victor 883 and/or 884. What are the default PWM widths for neutral (1.5ms?) full forward (2.0 ms?) and full reverse (1.0 ms?).

Many thanks and enjoy what’s left of your summer!

Tim Skloss

2

On PWM Outputs

Red = +5V
Black = Gnd
White = Signal

The signal is compatible with that of a hobby servo so I would venture to guess a 1ms puls min to a 2ms pulse max with a 40ms delay between pulses. Hope that helps!

3

Actually, I know that already. What I’m looking for is the specific timing (down to microseconds) for the default Victor 883/884 control signal at full fwd/rev, neutral and deadband.

And what the control signals to the Spike BLUE look like. (CMOS, TTL, serial?)

I could measure it myself if I get time in the lab, but I wanted to see if anyone knew off hand.

And it would be good to record this in the delphi database for future reference.

Tim

4

Please see thread:
http://www.chiefdelphi.com/forums/showthread.php?s=&threadid=21568

5

Great. According to the (rather long) thread above, Innovation First has said that the Victor expects a pulse width between 1.0 and 2.0 ms for full fwd-rev control (1.5 ms pulse width is center). I had assumed this but wanted to hear it from someone else. The 17ms delay between pulses is approximate. The industry standard is 20 ms period for the square wave (20 ms period minus a 2ms positive pulse = 18 ms delay). In my experience the delay can vary from 15 to 25 ms. Some servos (or speed controllers) can tolerate more or less so stay as close to 20 ms as possible. For BS2 a delay 18 should be OK. If you get jitter in the control or nonlinearity, try delay values between 17 and 20.

Now, does anyone know how to wire a Spike BLUE to a BS2?

Tim

6

Spikes have a ground (Black) and two “signal” leads, going to two optoisolators. one for either relay circuit in the Spike. +5 V to ground should turn 'em on.

7

Mission Accomplished!

Many thanks to those who helped answer my questions.

-Tim