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MIDIsense Resistive - no response to sensor
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MIDIsense Resistive - no response to sensor

by GBaz on Wed Feb 27, 2008 12:51 pm

Hi,
I successfully built the MIDIsense resistive board. I am able to connect to the software. The green led flashes and the MIDIsport UNO receives midi data. I can configure the sensors (i see the red led flash)
I am using the included photo sensor with the included 1k resistor. When i go to calibrate the sensor the bar does not move. i am using a green laser and flashing it on and off but get no response displayed in the software.
I have tested the photo resistor. With little to no light the resistance is 300-500k. When lit with the laser dead on it reads 1.4k. Measurements have been taken with a fluke 289

I don’t think this should make a difference but I soldered the 1k resistor directly to the sensor and used a jumper on the board where the resitor goes. This way I don’t have to deal with desoldering the board to change out a sensor. I am connecting the lead with the resistor to the right pin of each terminal (the one the connects to where the resistor jumper is.) I also used sockets with the 3 chips in additon to the included one.

Any input would be great. I tired to provide all information but if you need more please ask. Thanks.
GBaz
 
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Joined: Wed Feb 27, 2008 12:28 pm

by GBaz on Wed Feb 27, 2008 3:00 pm

I just checked the open voltage at the sensor. i have a jumper ar R106 so there is no resisot in place. voltage is 0.45. With the photo sensor and 1k resitor (metered above the resitor) voltage is 0.4-0.45 with low light and 0.09v with laser light.
GBaz
 
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Joined: Wed Feb 27, 2008 12:28 pm

by adafruit on Thu Feb 28, 2008 3:04 am

i hope you mean "10K" not 1K resistor

adafruit
 
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by GBaz on Thu Feb 28, 2008 10:33 am

yes sorry 10k
GBaz
 
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by adafruit on Fri Feb 29, 2008 5:23 pm

those voltages are way too low, try a larger resistor, like 100k

adafruit
 
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by GBaz on Mon Mar 03, 2008 4:59 pm

0.45 volts is the voltage on the sensor without a resistor! I put a bridge wire at R105 and R106. I am measureing for the terminals of the connecter. When I measure before R10 i get 5.04 volts if i meter after it I get 0.45v. The resistor is gold/orange/black/brown 10 Kohms, +/-5%.
GBaz
 
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Joined: Wed Feb 27, 2008 12:28 pm

by GBaz on Mon Mar 03, 2008 6:07 pm

Ok im an idiot. It seems I only got 1 10k resistor and was using a 1k by mistake. I got it working using a 10k linear-taper potentiometer. Sorry for wasting your time.
GBaz
 
Posts: 5
Joined: Wed Feb 27, 2008 12:28 pm

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