[SOLVED] FEZ Mini and Sharp GP2Y0A02YK

NETMF & Gadgeteer
1

Hi there,

I cannot get this to work.

I have:

Tried different settings, but nothing works. I only get, or same results, e.g. 24 cm, or distance is counts down from e.g. 80 to 0 and further.

Anyone?

2

how are you connecting power to the sensor?

3

Connected through standard JST3AA cable.

3 pin cable.

  • red = power
  • with = signal
  • black = ground

Picture attached.

4

I have read on this forum, there is a problem with the wiring on the Sharp Distance Sensor.

I bought this sensor from http://www.antratek.nl/.

Like I said, i have connected the sensor through standard JST3AA cable.

Cannot find out which cables I have to switch to let it work.

Normal JST3AA cable has the following colors, from left to right:

  • Red (power)
  • White (signal)
  • Black (ground)

I did find the papers from this sensor saying it should be like this:

  • White (signal)
  • Black (ground)
  • Red (power)

But! When I do this, the sensor isn’t working and get’s a really bad smell and hot after 10 seconds connected.

What the hell I am doing wrong.

5

You probably have damaged the sensor already :frowning:

The sensor pinout is different that FEZ 3-pin eblock pinout. The sensors GHI sells already come with cable that switches the wires

6

Well, luckily i had ordered 2 (of the same) sensors. So, I’ve got one ‘spare’ :wink:

So. How do I connect the Sensor correctly to the FEZ Mini. See picture above.
And how do i connect the wires correctly?

7

I never done the cable because we have the cables premade. The FEZ tutorial shows the JST connector pinout of our 3-pin eblock then you can lookup the pinout of the sensor from its datasheet

8

Gus, i’ve done that, but didn’t work out. Hot and smelly :S

This is what i’ve done:

1 side is: Normal JST3AA cable has the following colors, from left to right:

  • Red (power)
  • White (signal)
  • Black (ground)

The other side is what i’ve found in the sheets (http://www.antratek.nl/pdf/gp2y0a02yk_e.pdf)

  • White (signal)
  • Black (ground)
  • Red (power)

But! When I do this, the sensor isn’t working and get’s a really bad smell and hot after 10 seconds connected.

Any suggestions? Can you look at the sheet for me and tell me what i might doing wrong?

9

I wouldn’t rely on colors for signals. Did you check the FEZ tutorial for correct pinout?

10

Well, I have a FEZ Mini Robot Kit. This comes with a controller board. On this board you can see next to A7 the pinout. + S - (see picture attached).

So, assumed this is the right pinout, it still is:

  • Red (power)
  • White (signal)
  • Black (ground)

In the PDF document of the Sharp Sensor it says that the pinput is:
① Output terminal voltage VO
② Ground GND
③ Supply voltage VCC

I have translated this to colours of the JST cable and have reconnected the wires to the correct pin:

  • White (signal) (1)
  • Black (ground) (2)
  • Red (power) (3)
11

This is a 5 volt device. Does the robot board feed it 5 volts or 3.3.

12

When unsure, just verify with your voltmeter. Couple seconds you got it.

13

Check your voltage and re-check your pin out. I will check it out too.
As fas as I know, I never switched any prefab cables. However I do believe that I bought them from tinyclr. Not sure though, so that might explain.

14

@ Foekie, will check the voltage and did multiple re-checks on the pin out.
I bought this sensor from http://www.antratek.nl/.
And used the standard JST cables of the FEZ Mini Robot.

15

In your first picture, the sensor is indeed connected wrong.

Can you take a picture of your connection (both ends) after you’ve switched the wires?

16

If the print on the board is correct and the datasheet you referenced is correct.
Then I think you should connect it like shown in the modified picture below.

17

Hi Wouter,

Thanks for your reply. I did this, reswitched the wires a few days ago, like this:

Normal JST3AA cable has the following colors, from left to right (connected on the FEZ Mini, like on the picture of Wouter):

  • Red (power)
  • White (signal)
  • Black (ground)

I did find the papers from this sensor saying it should be like this (connected to the Sensor, see the colors of the wires, the same ;-)):

  • White (signal)
  • Black (ground)
  • Red (power)

See new picture attached.

But! When I do this, the sensor isn’t working and get’s a really bad smell and hot after 10 seconds connected.

I have a battery of 4 x AA batteries (1.5V each, 6V total).

Still have to check the voltage on the - and + pins of (e.g.) An7.
(Don’t have a working Voltagemeter in house :frowning:

In the mean time, any suggestions?

18

The Robot feeds 4.8V to the analog pins.
Just checked this with a Voltagemeter.

19

Also, when reading the battary voltage within NETMF.

Starting up FEZ Mini Robot.
OEM String: GHI Electronics, LLC
Version: 4.1.3.0
Battery: 3700
Sleep Infinite.

Code i used:

            Debug.Print("Starting up FEZ Mini Robot.");
            Debug.Print("OEM String: " + SystemInfo.OEMString);
            Debug.Print("Version: " + SystemInfo.Version.ToString());
            Debug.Print("Battery: " + Battery.ReadVoltage().ToString());

Any help?

20

So, Supply voltage (4.5 to 5.5 V) of the Sensor is correct. I read 4.8V on the analog output pins.

Checked the cables again, they look fine. But when i turned it on a few days ago: