Replacing Parallel Port with Mesa ?

I am desiring to replace my parallel port configuration with a Mesa card. I hope someone can confirm, or refute, my thinking before I order the Mesa card.

I have a old stepper system using a PMDX-131 breakout board with three Gecko 202 drives. This plugs directly into my computer parallel port. The computer is currently an Intel Atom mini-ITX system running LinuxCNC 2.7.0. Currently the three steppers are the only connections. I may, during this upgrade, add limit switches and vfd speed control. I have a PMDX-107 that should plug into the PMDX-131 for spindle control and a fourth Gecko (G201X) for an eventural fourth axis. This is the first system to upgrade with a Mesa card.

I'll also likely upgrade a small Sherline system. It uses a very similar computer with parallel port connected to a Gecko G540. This is on a lathe and has an encoder on the spindle. It's also running LinuxCNC but I believe a newer version.

I believe I can obtain a Mesa 5I25 card(s) and hook directly to the PMDX-131 (or G540) breakout board. Then configure LinuxCNC using pncconf. Is this correct?

I think the Mesa G540x2 firmware would be a good start for both systems. Is this a reasonable start? Do I order the Mesa card with the G540x2 firmware or burn this myself?

Thank you for any advice or direction you can offer. Thanks in advance.

Hugh

That is encouraging. It is running under LinuxCNC through a standard parallel port.

The PMDX-131 is an old breakout board replaced with the 132 which is now also a "legacy" product. I think it's a pretty generic breakout board but it's been years since I dug into the manual.

Thank you for the reply.

Hugh

There is a PMDX-126 configuration for 5I25 or 7I92
which may be close.

Normally you would update the firmware yourself using the
"mesaflash" utility

There is no direct support for GUI configuration for most
parallel port breakouts (including PMDX) but you can use pncconf
with a similar breakout (say G540x2 or prob_rfx2 )
firmware and then edit the created hal file to adjust for
the differences.

The PMDX-126 is one suggested replacement for the PMDX-131. Probably not identical but likely very close. Is that configuration, PMDX-126, a firmware for the Mesa card or a selection within pncconf? If a selection in pncconf then what firmware would be loaded to the Mesa 5I25?

With the help of this forum, some simple modifications to the HAL file should be doable.

I am encouraged. Thank you.

Hugh

I think the only parallel port like configurations for the 5I25 that pncconf
supports are G540x2 and prob_rfx2. but either of these are probably an
adequate starting point for a configuration using PMDX126/131 firmware

If the PMDX131 requires slight different firmware, it will be easy enough
to make matching firmware starting with the PMDX126 pinout source file

Thanks. The Mesa manual for the 5I25 lists both the G540x2 and prob_rfx2 but gives little detail. The prob_rfx2 mentions an encoder so may be a slightly easier starting point.

I'll order a Mesa 5I25 and start digging further when it arrives. I anticipate questions for the forum when it arrives.

Thank you for the help.

Hugh

if you download the 5i25.zip file, in
/configs/hostmot2 there are various bitfiles
and .pin files that list the pinouts of the
corresponding bitfiles.

I ran across this download when trying or order the card. Don't know how I missed it before. I have it now, but know there will be more confusion and questions coming.

Thanks again.

Hugh

Hi Hugh (I am also on MEM
I am following a very similar process using a 7i92 and PMDX-132. 4 G201 drivers.It will drive my soon to be completed fixed gantry mill/router.

I went with the 7i92 in place of 5i25 because it is ethernet, not plugged into a slot in the PC. For me it makes easier wiring. From everything I have read the 5i25 and 7i92 are pinout-to-breakout compatible. It apprears to be 1 or 2 lines of config change in the .hal file to switch between 5i25 and 7i92

Mine will be used with PathPilot once up and running on LinuxCNC.

Gerrit (gerritv on most forums)