7i76 Spindle Output Not working

I first run linuxcnc and then from the Hal Command window run 
"unlinkp hm2_5i25.0.7i76.0.3.spinout"  which is successful.
Then I run
"setp hm2_5i25.0.7i76.0.3.spinout 10"  which is successful,
but when I read the voltage between pins 1 and 2 on TB4 I always see 0 volts.
I have +12 volts between pins 1 & 3 (supplied by the spindle drive).
No matter what I set spinout to, I read 0 volts with the volt meter.
Does this mean the 7i76 board is damaged?
Or am I missing something in software?

Thank you,
Mike


 

7i76 spinena is on.
My spindle drive provides +12,  -12 and common for the input signal.  I may have damaged the digital pot chip by applying -12 to pin1 and +12 to pin 3 on 7i76 TB4 until I realized that the 7i76 book says 15 vdc max.  At this point, I will have to replace the chip because I can't afford a new 7i76.  Does that seem like the right thing to do?  Does Mesa provide any more information on how this circuit works?

Thank You,
Mike

Yes, its likely you damaged both the OP-Amp (NE5230 or TLV2371) and CD4001 parts on the 7I76 by applying 24V

Thanks for your help! 

I ordered the TI op amp since it's good for 16v instead of 15v.

 

I replaced the rail to rail op amp and the quad nor gate (CD4001) chip but it still doesn't work,
so I ordered a new 7i76. What units does the 7i76 spinout value use?  Volts?
I can set it to anything I want using the halcmd setp but it always reads
the same as the positive supply voltage provided by the spindle controller to TB4 pin 3
at TB4 pin 2 (spinout).  

Thanks,
Mike

The output scaling is usually set with the ini parameter OUTPUT_SCALE
in the SPINDLE_0 section of the ini file (current LinuxCNC versions
and pncconf created hal /ini files)

When spinout = the output scale value, you get 100 % output (spinout = SPIN+ voltage)
Normally OUTPUT_SCALE would be set for max RPM

Thanks, I set OUTPUT_SCALE to 1800.
I installed a new 7i76 board and the output is the same as the 1st board I repaired.  No matter what I set "spinout" to, the output at TB4 pin2 is100%.   Could I have wrong firmware in the 7i76? 
TB4 pin1== 0 volts
TB4 pin2== 12 volts

spinout== 1800     12volts on pin2
spinout== 0            12 volts on pin2
spinout== -1800  12 volts on pin2

What is TB4 pin2 relative to TB4 pin1 when LinuxCNC is not running?

With LinuxCNC not running:

TB4 Pin1 == 0 volts
TB4 Pin2 == 0 volts
TB4 Pin3 == 12 volts


Thanks,
Mike