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Pi-Plates DAQC2plate - Pulse Width Modulation (PWM)

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addr must be in the range of 0 through 7
channel must be in the range of 0 through 3
setDAC(addr,channel,value) - set DAC output voltage from 0 to 4.095 volts.
getDAC(addr,channel) - return current DAC output voltage. Returned value will be between 0 and 4.095
volts.
Auxiliary Power Supply
The DAQC2plate has a pair of terminals on the Extended Functions block that allow the use of a high quality
power supply. Reasons you may want to use this feature include:
You plan to stack a lot of Pi-Plates
You need more power for your digital output loads
You plan to operate the DAQC2plate in Motor Controller mode and want to use 5VDC stepper motors
There are a few rules when using this input:
1. It can't be used with a power supply plugged into the RPI. Well, it -can- but it won't buy you anything
and we can't guarantee it will work with future versions of the Raspberry Pi.
2. Do not exceed four amps of current - the reverse bias protection circuitry will not like it.
3. Be sure to use a high quality supply with internal fusing. A UL or ETL mark is a good indicator of this.
4. If you use more than one DAQC2plate or DAQCplate in your stack, only one can be used for providing
Auxiliary Power. By design, accidentally hooking up multiple supplies on multiple DAQCplate boards
should not cause any damage but, only one of the supplies will be providing current.
Usage
1. Power down your stack and unplug the power supply currently attached to your Raspberry Pi.
2. Referring to the image below, loosen the screws on terminals 6 and 7 on the Extended Function Block
3. Noting the polarity, push the positive and negative wires of your power supply into the AUX 5VDC IN
and Ground terminals and tighten the screws. Don't worry if you accidentally connect it backwards - the
reverse bias protection circuit will prevent any damage.
4. Plug in your power supply and start coding!
PWM
These two outputs are located on pins 9 and 10 of the Extended Functions block.
Specifications
All outputs have ESD Protection
10 bit resolution
Oscillator frequency of 15.9Khz
Output swings from 0 to 5VDC - note that this output is unregulated
Functions
addr must be in the range of 0 through 7
channel must be a value of 0 or 1
value is a floating point number that can range from 0.0 to 100.0
setPWM(addr,channel,value) - set PWM signal from 0 to 100%
getPWM(addr,channel) - return current PWM setting. Returned value will be a number between 0 and
1023.