Request: Custom 7C80 bitfile - Replace StepGens 0, 1, 2 with PWMGens (TB7, TB8,

Hi LinuxCNC community,I am running a Mesa 7C80 via SPI on a Raspberry Pi 5. Because my main axes and spindle are handled over EtherCAT, I am not using the standard StepGens.I need to drive three linear coil motors that require a standard 5V hardware PWM signal. Could I please request a custom bitfile that replaces the first three StepGens with PWM Generators?Specific Routing Request:

• TB7 (Normally StepGen 0): Replace with a PWMGen.
• TB8 (Normally StepGen 1): Replace with a PWMGen.
• TB9 (Normally StepGen 2): Replace with a PWMGen.

Ideally, I would like the primary pin on each of those terminal blocks to act as the PWM output, and the secondary pin to remain available as a standard GPIO so I can use it for the Direction signal.Thank you in advance for your time and all the support you give this community!

So you want the DIR pin to be GPIO rather than PWM direction?

( The PWM direction pin is controlled by the sign of the PWM value )

Hi,

You are completely right. I took a step back and realized it makes much more sense to update my GUI to use a -100 to +100 slider so I can take advantage of the hardware direction.

So YES, please link the DIR pin to the PWM direction (your standard way).

Thank you for catching that and pointing me in the right direction!

 


Note that to get 0 PWM at startup or watchdog bite you may need to

1. Chose the output polarity that is 0 at startup ( I think this is the - pin )

2. Invert the PWM output in HAL