Additional stepper drivers on Duex 5
Hi, can I connect two additional external stepper drivers if I am already using a Duex 5 expansion board? I have read that I could use the CONN_LCD connector pins? Is there a description for that somwhere?
Okay, finally got the drivers from oriental but I am not sure about the nomenclature:
stellator last edited by stellator
Attempting to connect via Conn_LCD I think I should connect the following pins (assuming Duet uses a "current sink output design" and gives "1 puls signals" as they call it in the oriental manual) :
Conn_LCD to Oriental CRD5114P (see image above)
pin 10 ) Step11 to be connected to pin 1) PLS+
pin 2 ) GND to be connected to pin 2) PLS-
pin 8 ) DIR11 to be connected to pin 3) DIR+
pin 2 ) GND to be connected to pin 4) DIR-
pin 6 ) EN11 to be connected to nothing?
pin 4 ) Stop11 to be connected to no clue!
You could also connect AWOFF+ to EN and AWOFF- to ground.
Two points to note:
The CONN_LCD connector provides 3.3V signals with low current drive. That may not be sufficient. You can use a 74HCT367 or similar chip to boost the signals to 5V.
You will need to extend the step pulse timing for that driver in the M569 command.
For a 74HCT365 or 74HCT367 (either will do) in 16-pin DIL package:
Pins 1,8,15 - ground
Pin 16 - +5V
Pins 2,4,6,10,12,14 - inputs from CONN_LCD
Pins 3,5,7,9,11,13 - +outputs to stepper driver +input pins (connect the -input pins of the stepper driver to ground)
Also connect a 0.1uf capacitor between pin 16 and ground.
A few stepper drivers have a common +input pin. For those, use a 74HCT366 or 74HCT368 instead, connect the driver -input pins to the outputs of the chip (pins 3,5 etc.), and connect the common +input of the driver to +5V.
Take great care not to short +5V to any of the other pins on CONN_LCD.