Where would you connect the +5V on the 2740c driver? If you are looking for something to connect to the SP+/DIR+ pins, then you can use the "COM" pin on each PMDX-424 step/dir connector, and configure the PMDX-424 "step/dir common" to +5V. Then connect the PMDX-424 step/dir pins to the SP-/DIR- pins (and configure the PMDX-424 step/dir as "active low". Or as an alternative, you can connect the step/dir signals to the SP+/DIR+ and then connect the SP-/DIR- to the PMDX-424 "COM" terminal, and configure the PMDX-424 step/dir common for GND and step/dir polarity as active high. There are articles on the PMDX FAQ site about this (
https://faq.pmdx.com/index.php?solution_id=1010).
If that is not what you are asking about, can you give us a little more information?
