Using a Diamond Hotend for my Ormerod printer put me in the position of needing more stepper driver. The Duet Board for the Ormerod I and II has only 5 stepper driver. For the Diamond Hotend I need at least one more. This is where the extension header comes into play.

The official Duet Extension is more expensive but brings four more stepper drivers and heater channels. It is about the same size as the Duet board. This is way to much for what is needed here.

So I created a small board that hooks directly onto the extension header.

If you get the Kit version you have to solder SMD resistors yourself!

You can install the board to the extension header on the top of the Duet board. For firmware configuration you have to modify the config.g on your SD card.

• G10 P0 S220 R120 ; add tool 0 with 120° standby and 220° working temperature
• G10 P1 S220 R120 ; add tool 1 with 120° standby and 220° working temperature
• G10 P2 S220 R120 ; add tool 2 with 120° standby and 220° working temperature
• M563 P0 D1 H1 ; configure tool 0 to use drive 1 for extrusion and heater 1 for temperature
• M563 P1 D2 H1 ; configure tool 1 to use drive 1 for extrusion and heater 1 for temperature
• M563 P2 D3 H1 ; configure tool 2 to use drive 1 for extrusion and heater 1 for temperature

This way you tell the firmware to use drive 1,2 and 3 for tools 0, 1 and 2.

Alternative use

You can also use the board as alternative XYZ motor driver if some of them are burnt on the duet board. Use M569 and M350 to remap the drives to the corresponding motor.