Mesa 7i95

Hi Peter,

Thanks for your help... I've had success getting the 7i95 board working with the latest head branch from git.

I'm mapping out all my pins in HAL to make things work now.

I'm looking at spindle control. From what I'm reading, it sounds like I need to somehow re-purpose one of the stepper outputs to generate a PWM signal for spindle control. I also need a 3 more very low power (~5mA@5V) single ended outputs for CW/CCW direction and an enable signal.

I'd like to preserve the SSR outputs for switching coolant, lube, etc if thats possible. Seems a waste for SSRs to be doing such light duty.

I also intend to put an encoder on the spindle for rigid tapping, so I'm assuming the 6th encoder input can just be used as-is for this?

Whats the best way to achieve this? Does it require customised firmware or parameters when I 'loadrt hm2_eth .....'?


Sorry if these are dumb questions - I guess this is the price I pay for being new to LinuxCNC, Mesa, and picking a card to use thats not yet supported by the "stable" version of LinuxCNC.


Cheers!
Shaun

I guess I would still prefer the SSRs for this duty because of the isolation they offer
Normally you would need only 2 control lines in addition to the PWM
(FWD/REV or alternatively ENA/DIR)

Another option would be to use an inexpensive parallel port breakout board
on the 7I95s expansion port.

You can use any encoder for spindle feedback but encoder 5 (of 0..5) probably makes the
most sense as it does not alter the 0=Y 1=Y 2=Z... convention used in most configurations.

PCW wrote: 1.
2. There is currently no pncconf support for the 7I95 but you could use a 7I96 configuration
file set if you replace all occurrences of '7i96' with 7i95. You would also have to edit any input pin
connections to use the 7I95s different input pin names.

If someone can supply the HAL pin printout and the hostmot2 PIN file printout - I could work on support
Also 2.8 + pncconf has an INI substitution option that allows you to change the mesa card in the INI file which might be helpful for renaming.

Chris

I can do this sometime this evening, I have a 7I95 setup

So you're saying I can generate PWM in hardware on one of the SSR outputs?

That would work for now, and I'd add a breakout board on P1 for more outputs as you suggest.

I'm using a Homan Designs Digispeed DC03 GX V3 board for isolation between the Mesa and my spindle controller. Isolation is needed because inputs in the VFD float near mains potential. Its a Sieg brushless motor and controller that came on my mill.

www.homanndesigns.com/index.php?main_pag...ncj79miq92t8amiklfe0

I'd be happy taking some GPIO from elsewhere to drive the DC03 board, and saving the SSRs for switching heavier loads via relays.

Cheers!
Shaun

You could use the parallel expansion port for driving that interface
Just make sure you have common grounds before you connect signals