Digital Side Car Wiring Of I/O & Solenoid Output Card

[James Lightfoot]

Hello,

1st year mentor and under the gun. I have a few quick questions about connecting I/O to the Digital Side Car and Solenoid card
1) Encoders [US Digital E4P-250-250-N-S-D-D-B encoder (am-0174)] connect to 2 GPIO points (Channels A & B), correct?
2) Are the GPIO points both Inputs and Outputs or just Inputs?
3) Do the GPIO points use the same connectors as the premade PWM cables?
A)If so, how do we connect "extra inputs & outputs (either via the GPIO
or Relay points) that do not come w/ premade cables?
3) We are using and ultrasonic sensor (Maxbotix MB7366) that has 3 output options (Analog Voltage, PWN, Serial). Can we connect the PWN singal to a GPIO as an input or do we have to use the Analog input route?
4) We are using an electromagnet that uses 12VDC. Can we connect that directly to Solenoid Output card or should I use an interposing relay (24VDC coil) and then use a NO contact to energize the electromagnet?

Thanks all,

[cgmv123]

Originally Posted by James Lightfoot

1) Encoders [US Digital E4P-250-250-N-S-D-D-B encoder (am-0174)] connect to 2 GPIO points (Channels A & B), correct?

You need 2 channels to use a quadrature encoder properly. One of the Channels will provide power in addition to being an input channel. The other is just a channel.

2) Are the GPIO points both Inputs and Outputs or just Inputs?

GPIO means General Purpose Input/Output. Each pin can be either input or output depending on software.

3) Do the GPIO points use the same connectors as the premade PWM cables?
A)If so, how do we connect "extra inputs & outputs (either via the GPIO
or Relay points) that do not come w/ premade cables?

Yes, PWM outputs, GPIO, Relay outputs and Analog inputs all use the same connectors.

3) We are using and ultrasonic sensor (Maxbotix MB7366) that has 3 output options (Analog Voltage, PWN, Serial). Can we connect the PWN singal to a GPIO as an input or do we have to use the Analog input route?

The Maxbotix sensor PWM output can be read by the GPIO. There may be more coding involved than using the Analog Voltage method.

4) We are using an electromagnet that uses 12VDC. Can we connect that directly to Solenoid Output card or should I use an interposing relay (24VDC coil) and then use a NO contact to energize the electromagnet?

It depends on how much current your electromagnet uses. If it's less than .75A, then you can use the Solenoid Breakout. If not, then you can use a Spike, which can handle up to 20A continuous.

[Jon Stratis]

A few notes for your electromagnet...

Per Q&A 217

If the electromagnet causes movement, it is covered by R29. If the electromagnet only creates an attraction force, it is legal as long as it meets all other applicable rules.

So if your electromagnet causes movement, it's considered an electrical solenoid actuator, and per R29:

Electrical solenoid actuators, no greater than 1 in. stroke and rated electrical input power no greater than 10 watts (W) continuous duty at 12 volts (VDC)

[DonRotolo]

Originally Posted by James Lightfoot

3) Do the GPIO points use the same connectors as the premade PWM cables?
A)If so, how do we connect "extra inputs & outputs (either via the GPIO
or Relay points) that do not come w/ premade cables?
4) We are using and ultrasonic sensor (Maxbotix MB7366) that has 3 output options (Analog Voltage, PWN, Serial). Can we connect the PWN singal to a GPIO as an input or do we have to use the Analog input route?

3A: Unfortunately you will have to wire it up yourself. We use 2 standard cables and cut / strip what we need, soldering the connections.

4: Strongly consider using the analog input instead. The sensor delivers a voltage that is linearly and directly proportional to distance. For example 2.56 V is 256 inches, 0.83 is 83 inches. Your voltages may vary.

[James Lightfoot]

Thanks Don. I have a few quick question to clarify your last response.

3A1) For the Relay Outputs, I'm guessing that the A & B signal states [0 or 1] are controlled by the Java DigitalInput class, correct? Making pin A the PWM signal controlling a Spike Relay's FWD direction [depending on the code & wiring] a PWM signal of 1.0 to 1.5, correct?

3A2) For GPIO's, a discrete device like a Limit Switch will be "powered" by the available 5VDC on GPIO's pin 2, and the signal will connect to the GPIO's pin 1. Which leaves the GPIO's pin 3 tied to the DC Common bus,

3A3) For the Solenoid Breakout Board, the Outputs are sourcing also; hence, we would tie the Solenoid Output's + pin to the + terminal of a solenoid and the Solenoid Output's GND pin to a solenoids - terminal, correct?
I will not be surprised if tell I've all 3 of the above scenarios backwards.

4A) Will the voltage out on the "long range" ultrasonic sensor (3cm - 10m) also be linear but 5.3V = 5.3m?

Thank you very much.

[wireties]

Originally Posted by James Lightfoot

3A1) For the Relay Outputs, I'm guessing that the A & B signal states [0 or 1] are controlled by the Java DigitalInput class, correct? Making pin A the PWM signal controlling a Spike Relay's FWD direction [depending on the code & wiring] a PWM signal of 1.0 to 1.5, correct?

Use the Relay class - it works like this:

http://wpilib.screenstepslive.com/s/...hanisms-relays

Originally Posted by James Lightfoot

3A2) For GPIO's, a discrete device like a Limit Switch will be "powered" by the available 5VDC on GPIO's pin 2, and the signal will connect to the GPIO's pin 1. Which leaves the GPIO's pin 3 tied to the DC Common bus,

If it is a limit switch (a simple mechanical closure), connect the common and normally open (or closed) contacts on the limit switch to the ground and signal connections of a digital I/O port. Then use the DigitalInput class to read the state.

Originally Posted by James Lightfoot

3A3) For the Solenoid Breakout Board, the Outputs are sourcing also; hence, we would tie the Solenoid Output's + pin to the + terminal of a solenoid and the Solenoid Output's GND pin to a solenoids - terminal, correct?

Yes - this connection is correct. Use the Solenoid or DoubleSolenoid class to control the solenoids.

Check here: http://wpilib.screenstepslive.com/s/...ders-solenoids

and here: http://www.usfirst.org/sites/default...d_Breakout.pdf

Originally Posted by James Lightfoot

4A) Will the voltage out on the "long range" ultrasonic sensor (3cm - 10m) also be linear but 5.3V = 5.3m?

We use this one: http://www.maxbotix.com/documents/MB1020_Datasheet.pdf

The datasheets for each are on the maxbotix web site. For the MB1020 the analog number is VCC/512 per inch.

Good Luck!

[Mark McLeod]

Originally Posted by James Lightfoot

Making pin A the PWM signal controlling a Spike Relay's FWD direction [depending on the code & wiring] a PWM signal of 1.0 to 1.5, correct?

Just a quick additional point.
The two Relay signal pins (one for Forward, and the other for Reverse) do not output a PWM signal.
It is a simple steady voltage when on, and zero volts when off.

[James Lightfoot]

Originally Posted by wireties

If it is a limit switch (a simple mechanical closure), connect the common and normally open (or closed) contacts on the limit switch to the ground and signal connections of a digital I/O port. Then use the DigitalInput class to read the state.Good Luck!

Just so I make sure I get it:
GPIO Pin 1 to LS NO pin
GPIO Pin 3 to LS Common/Swing Point
GPIO pin 2 is not used

Correct or am I still getting it backwards?

[wireties]

Originally Posted by James Lightfoot

Just so I make sure I get it:
GPIO Pin 1 to LS NO pin
GPIO Pin 3 to LS Common/Swing Point
GPIO pin 2 is not used

Correct or am I still getting it backwards?

This is correct. In this case it would not matter if you were getting it backwards. The switch just shorts the signals going into the DIO port. The DIO inputs are pulled up internally so it will read '1' if pins 1 and 3 are not shorted and '0' if pins 1 and 3 are shorted.

Good luck!