These outputs drive external stepper or servo drives. They pass through high-speed optocouplers used as level-shifting buffers, but both sides of those devices sit in the logic domain — these outputs are therefore not isolated and are referenced to the board’s logic ground.

Parameter

Value

Signals

PULSE X/Y, DIR X/Y, ENABLE X/Y (J5); SYNC X, SYNC Y (J7)

Type

Open collector, no pull-up fitted on the board

Isolation domain

Logic — not isolated

Required pull-up

330 Ω to 4 kΩ, fitted externally, to 5 V

Maximum pulse rate

5 MHz (design value)†

Supply available for pull-ups

J5.39 (+5 V, fused 0.25 A) with return on J5.40

Pull-up resistors are required. No pull-up is fitted on the controller. Each of these outputs needs an external pull-up between 330 Ω and 4 kΩ before it will produce a logic level. Many drive inputs provide one internally — check the drive’s documentation. The +5 V on J5.39 is provided for this purpose.