Phidgets Forums

Hi Phidgets forum,

I am going to buy some Phidgets hardware interface for a project and have a question.

This is my need:

6 digital inputs: 3 buttons + 3 magnet sensors
7 digital outputs: 7 Leds (12v)
2 analog inputs (Joystick)
1 rotary encoder

Since I have many time this setup to buy, what would be the best choice?
"PhidgetInterfaceKit 8/8/8" looks to be the perfect match for this, but is it possible and easy to read the encoder using 2 digital in (A/B encoder inputs)?
I only have experience with arduino yet.

If I use the hubs modules I would need a lot of pieces...

Thanks for the precious hint.

There are a few problems with trying to read an encoder with standard digital inputs instead of a dedicated encoder interface:

- You'd have to write the encoder logic by hand (i.e. look at both A/B channels to determine current count and direction)
- The inputs may not be fast enough to register very high speeds
- you may need external circuitry depending on what kind of encoder you have (line driver, push-pull etc)

If you plan on running the LEDs at 12V, the InterfaceKit 8/8/8 is only able to provide 5V on the digital outputs so you'll need a dedicated LED board.

Here are the products I would recommend:

HUB0000 ($30)

2x DAQ1200 ($12/ea)(This is cheaper than using 1xDAQ1301 and simpler to use for buttons and magnetic reed switches)

1x LED1000 ($50)

1x ENC1000 ($15)

The 3 buttons and 3 magnetic switches would connect to the DAQ1200s, The 7 12V LEDs would connect to the LED1000, the encoder would connect to the ENC1000, and the joystick would use the remaining two ports on the HUB0000, since each port can either connect to another VINT Phidget or can be opened as a digital input, digital output, or analog input.

You need a lot more pieces when you use the VINT Hub and devices, but it's newer technology and usually cheaper than our direct-to-USB options (e.g. 1018 + 1032 + 1057 = $208)

Hi mrparadis and thanks for your quick reply,

I already have some LPD-3806 600rp encoder, which are working pretty well with arduino. I will use them for simple menu navigation with a disk, so the speed might not be a big problem. I just wonder if I could get a clear rotation using a simple code?

Using Vint Technology looks interesting... but the Led1000 is not easy to find in France where I need to ship it.

but I found the relay module, so I guess 2 of them could replace the LED1000 for my need, right?

https://www.phidgets.com/?tier=3&catid= ... prodid=720

If it's low speed and you're willing to handle the logic to convert A/B channel pulses to count and direction, you could probably use digital inputs. It looks like the encoder you linked has internal pull-up resistors, so no external circuitry would be needed.

Yes, you could use relay boards instead of the LED board to switch power to the LEDs. The LED1000 has some additional options- you can control the current and voltage going to the LEDs but if you just need on/off control then the relays will work fine.

Ok thanks.

But using those two relays in my setup would allow only one free hub port in the VINT hub for my joystick right? So I can not use this solution unless I add an extra hub for more analog inputs...

Another problem I see is that the LED1000 is only able to control led up to 5.6 V DC... so it looks like it is not enough for my 12v Led.

My mistake, you're right that the LED1000 won't be suitable for 12V LEDs.

You could use one REL1101 instead of the two REL1100s to save one port.