EMC and chinese board

[Bri4n]

I bought a driver board off of ebay a few years ago and it is very similar to this one.

4 Axis A3977 CNC controller for CNC Router Mill products, buy 4 Axis A3977 CNC controller for CNC Router Mill products from alibaba.com

I cannot find the timing values emc asks for in the stepper conf wizard; step time, step space, direction hold, and direction setup. The other question I had was in the wizard where you can configure the p port pins the first choice lists everything but what I need, my board is looking for pin 1 to be enable all. Enable all is not listed unless it is a communication issue and there is a different name that I am not aware of.

[jcoats]

You might be able to get some answers on the EMC2 mailing list.

[doorknob]

I do not have that board, and I am only just beginning to learn EMC2, so I can't answer your questions directly.

However I believe that you can obtain at least some of the answers that you need by looking at the datasheet for the Allegro A3977 controller chip. See http://www.allegromicro.com/en/Produ.../3977/3977.pdf

On page 9 of the datasheet it gives some timing waveforms that may be useful. For example, if I understand the meaning of "direction setup" correctly, that would be the minimum time required between asserting the Direction signal and asserting the Step signal. According to the timing diagram, it looks like that number is shown as:

A Minimum Command Active Time Before Step Pulse (Data Set-Up Time) ..... 200 ns

Similarly, Direction hold time is given as:

B Minimum Command Active Time After Step Pulse (Data Hold Time) ........... 200 ns

If EMC2's "step time" means the minimum step pulse width or step low time, then it shows:

C. Minimum STEP Pulse Width ...................... 1.0 μs
D. Minimum STEP Low Time ......................... 1.0 μs

So, you may need to verify the exact definitions that EMC2 uses for those signals, but you may be able to get what you need from the datasheet.

Since the values in the datasheet are the "raw" minimums for the chip, and not for that specific board, I would be conservative in choosing values to enter into EMC2 in case slow optoisolators or other possible delays may have been added by the board design.

[cncbasher]

for your pin1 enable , select amplifier enable in Hal , you may also need to use the invert option ,

the other option is to disable this either by connecting pin 1 to gnd or 5v
depending on the logic of the board , their may be a link to enable this to be done already .

[Bri4n]

Thanks for the help guys, I will be trying this as soon as time permits. I was hoping that someone on here had the same setup.....I cross posted this on the EMC forum as well.