The most basic configuration would be something like this for the first motor (I'll call it the "X" axis for convenience and to match the silkscreen on the PMDX-422). This presumes that you have kept the default PMDX-422 step/dir mapping of step signals on parallel port pins 2, 4, 6 and 8, and direction signals on pins 3, 5, 7 and 9 (go to the mach "Configure" menu and select "Plugins", then click on the "Configure" button on to the PMDX-SmartBOB line, then click on the "Motor Config" tab of our plug-in configuration dialog).
See the attached image for a drawing of these connections.
- Set PMDX-422 jumper JP3 (next to the relay) so that the shorting clip is between the center pin and the "GND" pin (this is the default as shipped from PMDX).
- On PMDX-422 connector J3, connect the "COM" terminal to both the DIRECTION- and CLOCK- terminals on the X axis driver
- Connect the PMDX-422 J3 terminal labeled "2" to the "CLOCK+" terminal on the X axis driver
- Connect the PMDX-422 J3 terminal labeled "3" to the "DIRECTION+" terminal on the X axis driver
- Connect the driver's "ON/OFF-" terminal to the "DIRECTION-" terminal, and connect the "ON/OFF+" terminal to the PMDX-422 connector J10 "+5S" terminal. This will enable the motor drivers only after the PMDX-422 has been powered on and the PC has finished loading the USB drivers for the board (i.e. all outputs on the PMDX-422 are idle and stable).
For the "Y" axis, repeat the above except use J4, with the "4" terminal for clock and "5" for direction. And so on for any other motors you need to connect. All of the motor driver's "ON/OFF+" terminals will need to be tied together and to the PMDX-422 J10 "+5S" terminal.
In the SmartBOB plug-in configuration dialog, on the "Motor Config" tab, set all of the "Step Polarity" items to "Active High" (this is the default). Also start out with all of the "Direction Polarity" items set to "Active High" (also the default). If you need to reverse the direction of any motor you can come back to this config dialog and change it. You should not need to change the step signal polarity.
NOTE: You can also change the motor's direction polarity from the Mach4 "Configure" menu, then click on "Mach". Click on the "Motors" tab and then click on "Motor0", "Motor1" or whichever motor you wish to change. Along the bottom of the window there is a check box for "Reverse?". This check box and the "Direction Polarity" setting from our config dialog reflect the same setting within Mach4. Changing it in one place will also change it in the other place. We include it in our config dialog as a convenience to be able to set all motor polarity settings in one place.
An alternative for controlling the motor driver "enable" (i.e. "ON/OFF") inputs is to use the PMDX-422's relay, if you aren't using it for anything else. You can connect the J10 "+5S" terminal to the "N/O" terminal on connector J8, then connect the "COM" terminal on J8 to the driver's "ON/OFF+" terminals. Then, in Mach4, assign the "Machine Enabled" output to "SmartBOB-USB" output signal name "Pin1", with a red "X" in the "Active Low" column (and hopefully obviously a green check mark in the "Mapping Enable" column). This will keep the motor drivers disabled until Mach4 is running AND you click on the "Enable" button in Mach4. This is not really necessary as a safety feature, but gives you the ability to easily de-power the motors in case you need to move an axis or motor by hand.
Bob
