Frequently Asked Questions - J Tech Photonics Pic-Convert Instructions Manual

Frequently Asked Questions:

Why do I need to have my steps per inch be so large?
The steps per inch needs to be something like 10,000 because we want the increment to be very small.
The axis is not really "moving" but rather just the step and direction pulses are getting produced. The
smaller the increment the faster the computer can produce the pulses.
Why is the maximum value a negative number?
This is because using a CNC the Z axis is normally for a mill or a router which has a maximum value as a
"depth". Depth is normally a negative because you are taking out material.
Can I make my maximum value a positive number?
Sure, if your machine is set up correctly. All the Pic-Convert™ board needs is the step and direction
signals. If your image comes out inverted, then you have them set backwards.
Can I use an axis besides the Z axis? I have the A axis available on my machine.
Sure. Set it up for the other axis like seen in the setup documentation.
My Parallel port card can't turn on the enable relay. What do I do?
You might need to look into a breakout board that has more ability to drive a signal. Some break out
boards have a "spindle interface" which have more power than standard lines.
I want to use a 5V power supply. Will this work?
Most of the other USB or wall adapters at 5V will not provide the voltage needed. Use more than a 6
volt supply and you will be fine. If you really want to use a 5V supply, then let us know and we will tell
you how to modify the board. It will require soldering skills.
I am adjusting my max value to larger than 256 increments and it is burning better. Can I adjust my
max over 256 levels? Does the DAC board compute anything for this?
Everything is all based on steps and direction. The Pic-Convert™ board doesn't compute anything, it is
just taking the step and direction from the mach3 controller and turning it into a PWM duty cycle.
The digital potentiometer on the DAC board has 256 "levels". On startup it is in the middle of the
range. Now, if the program says, "go to zero", then the output of the controller puts the DIRECTION pin
to Zero (this tells the digital potentiometer to DECREMENT the count). The controller then puts out the
appropriate steps to get the axis to 0. If the machine axis is located at -0.0255" and the steps are set to
10,000 then the controller will put out 255 "pulses" on the STEP pin. The DAC board will then
DECREMENT the count by 255 levels. This will put it at 0.
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J Tech Photonics, Inc. Pic-Convert™ Board Instructions V2.7 Copyright 6/13/17