7i76e pin configuration, flash firmware, do it in HAL files, etc. ???

I need a PWM generator for a spindle VFD.  I don't have any options to change that in the PNCCONF wizard.  Do I need to make some custom firmware for the board, or do I make some custom HAL files by hand?  I would like to repurpose some of the STEP/DIR pins for this since I'm only using 3 axes outputs from the board.  

my conversion

Why not use the Spindle control the 7i76e offers?

I had tried that but the VFD does not supply any voltage output. It is the original EMCO vfd and it does not have the most documentation available.

The original controls worked the VFD by supplying a PWM'ed signal, and it got a PWM signal in return for the spindle speed. It was beautiful how it all worked, really. If the two signals were the same the spindle was up to speed.

I had tried to use the built in spindle controller (the one in the mesa card) but with no luck. If I have to do lots of troubleshooting and such I figure I may as well make it work like it did originally as I have logic captures of how everything was working. There was no potentiometer signal.

The 7i76e_7i76x1pD bit file looks like what you want. It is the same as stock 7i76e but stepgen 5 is replaced with a pwm gen

You can download the source and already compiled firmwares here:

store.mesanet.com/index.php?route=produc...69_62&product_id=290

The Support Software is on the Specifications tab. If you unzip this file it containes the bitfile I mentioned above.

^ Thanks! ok one more odd thing is I need the (differential?) signals to enable the spindle. Or, atleast, that's how it was wired from the factory.

I suppose I can just use a regular GPIO? But I'd rather do it just like it is from the factory.

Is there anything I can do for that? Just about every signal to and from the VFD is this differential type, so I need the following all over two wires:

1. On/Off
2. Direction
3. Clock (commanded speed)
4. Actual Frequency (feedback to the PC)
5. Strobe (My spindle is not equipped with anything directly for this, but it may actually work based off signal from VFD I guess)
6. Servo Ready (signal to PC)

Is writing my own HAL file in my future?  I'm slightly confused by the results of my research.  Some say flash custom firmware, some say you write your own HAL file, and some say something else.  All I know is I can currently not do what I need in PNCConf

Direction and Clock sound more like a a variable frequency
than a PWM signal, If so, a normal stepgen should work

Do you have the spindle drive manual?

I do not have a spindle drive manual available, but I do have some documentation:

Pin out:
 

Wiring Diagram:
 

I Think this is the logic capture from the spindle.  I may not have saved the best file from that but it appeared to be PWM, 
 

Here's zoomed into the logic capture:
 



I do need to stress I did not do a perfect job organizing and storing my logic captures and I may have made a mistake but I am pretty sure that it was PWM, but without having access to the original controls anymore it's impossible for me to tell

if you zoom in on the signal from the CK pin this makes me believe it's PWM:
 

That looks like constant 50% duty cycle but variable frequency
so a standard stepgen should work.

^This makes sense, it is right at 50%.

I'm not confused about this part anymore, but, how on earth do I configure everything else? like the enable, how to I use the two wire signals to know theh servo is ready, etc? Do I work on a custom HAL file? Does the "actual frequency" go to an encoder, or do I just make some kindof input for it using two pins?

Enable could be driven by a spare step/dir output (if one more is free)
The driver ready can be read via the sserial RX input pair on the 7I76E
(assuming you are not using it for I/O expansion)

I don't think the "actual frequency" signal is of any use to LinuxCNC