The Stepper Motor Driver Board

Here is the Stepper Motor Driver  Board:

Almost no documentation in the Internet on this board! It is cheap and I have used it before.

Mapping/tracing the Nano pins I get:

• RX - Serial Receive (pin provided but not used)
• TX - Serial Transmit (pin provided but not used)
• D2 - X Direction
• D3 - Y Direction
• D4 - Z Direction
• D5 - X Step
• D6 - Y Step
• D7 - Z Step
• D8 - Enable
• D9 - +/- X End Stops (pin provided but not used)
• D10 - +/-Y End Stops (pin provided but not used)
• D11 - +/-Z End Stops (pin provided but not used)
• D12 - Free (pin provided)
• D13 - Free (pin provided)
• A0 - Abort (pin provided but not used)
• A1 - Hold (pin provided but not used)
• A2 - Resume (pin provided but not used)
• A3 - Coolant Enable (pin provided but not used)
• A4 - SDA (pin provided but not used)
• A5 - SCL (pin provided but not used)
• A6 - Free (pin provided)
• A7 - Free (pin provided)

There are also:

• +5v0 and ground pins
• +3v3 and ground pins (uses an on board regulator)
• Reset button (for Nano)
• E-Stop pins (same as reset)
• The power plug (Motor Power 8-12v):
  • Powers the Nano and via a shunt powers the A4988 stepper motor boards.
  • Otherwise the A4988 boards and the Nano are powered separately.
• Under each A4988 stepper motor board are pins to shunt (S) the micro-stepping:
  • MS1 MS2 MS3 (up view)
  •      -        -       -  Full Step
  •      S       -       -  Half Step
  •      -       S       -    1/4 Step
  •      S      S       -   1 /8 Step
  •      S      S      S  1/16 Step   

WATCH OUT!

One fault with these boards is that the shunts to control the micro stepping does not work. I added these 10k pull-ups to fix the problem:

Grbl

Pre-processing "cartesian" gCode with gCode2SCARA allows the use of Grbl for a SCARA arm (UVZ type). This what I would recommend to get started.

Not Grbl

Is some code that I wrote that will also do the job.

Motion Controller

Is some more code that I wrote (but needs some work of the interpreter) that could also do the job. I intend to finish this code off to work with gCodeFilter and gCode2SCARA at some point of time.

gCode2SCARA Command Line Options

If you have not realised, gCode2SCARA is a command line program program designed to be used via a batch file. Here are the current options:

• -i       Input File

• -o     Output File

• -t      XY Space Tolerance (mm)

• -s     UV Space Tolerance (full steps)

• -xc   gCode X Offset (mm)

• -yc   gCode Y Offset (mm)

• -L1   Arm 1 Length (mm)

• -L2  Arm 2 Length (mm)

• -M1  Motor 1 Steps

• -M2 Motor 2 Steps

This project could benefit from a "Visual Windows" programming approach, so probably time to look at what is available for Linux that is simple to use.

AlanX