Messages

1

Parallel Port breakout boards, motherboards, and dedicated accessories / PMDX-126 Input LEDs

« on: September 21, 2016, 02:37:28 PM »

On my CNC, I use NC switches for the X/Y/Z limits.  I go this route so that if a wire happens to get cut or disconnected, it will act as a failsafe and trip the limit.  The LEDs for the inputs of the PMDX-126, however, are on when the input-to-GND connection is closed.  So, under normal operating conditions, all my inputs connected to the NC limit switches are turned on.  Is it possible to reconfigure/reprogram the PMDX-126 to invert the logic on the LEDs and have them turn on when a limit switch is opened?  If it can't be done, it would be a good idea on the next rev of the board to include that option.  For now, I can make a separate board with an OC inverter or transistor on each limit switch to get the state I'm looking for.

2

General Discussion / Re: PMDX Warranty -How Long?

« on: September 14, 2016, 09:08:28 PM »

I received the boards today.  The quality looks pretty good.  I have just one suggestion for the next rev:  apply a conformal coating to the front/backside of the boards.  The conformal coating would prevent any corrosion from poor air quality.  Given the types of environments where the boards operate, I would imagine the air quality isn't very close to ideal.

Overall, it looks like a good product.  I'll be putting the board through its paces over the next week.

3

General Discussion / Re: PMDX Warranty -How Long?

« on: September 10, 2016, 09:22:51 PM »

Wow.  Thanks Steve for the speedy turnaround on a Saturday evening.  I just placed  my order for a PMDX-126, PMDX-107, and some limit switches.

Thanks,
Bob

4

General Discussion / PMDX Warranty -How Long?

« on: September 10, 2016, 08:23:19 PM »

Hello PMDX,
I would like to get clarification on the warranty for the boards that PMDX offers.  The Warranty & Repair section of the website says the items have a 1 year warranty.  But the manuals for the boards say they have a 90 day warranty.  Which is correct?

5

Parallel Port breakout boards, motherboards, and dedicated accessories / Re: UC100 Plus PMDX-126 Expanded I/O & PMDX-107

« on: August 22, 2016, 05:50:35 PM »

I get it now.  I saw the statement in the PMDX-126 manual that the 8 data bits of the second parallel port can be supported with the optional PMDX-108 board.  I glossed over the fact that even without those 8 data bits, the second port offers 4 dedicated inputs on pins 11, 12, 13, and 15.  I suppose if I still needed more than 8 inputs, I could still use a USB smoothstepper with only 2 ports and wire it as shown in Figure 5 of the PMDX-108 manual.  But I'm leaning towards the smoothstepper ESS just to have better noise immunity.

6

Parallel Port breakout boards, motherboards, and dedicated accessories / Re: UC100 Plus PMDX-126 Expanded I/O & PMDX-107

« on: August 22, 2016, 01:49:23 PM »

OK.  Thanks Steve for the quick reply.  I guess I'll be migrating to the smooth stepper ESS then.  And with that, I won't need the expanded mode on the PMDX-126 since the smoothstepper supports 2 LPT ports natively when used with the PMDX-126.  Now, in reading the documentation, I believe a PMDX-108 should also be used for protection on the additional inputs.  All in all, it looks like I need:  Smoothstepper ESS, PMDX-126, PMDX-107, PMDX-108, and 3 ribbon cables to connect the boards together.  Does that sound about right?  I'm kicking myself for not having planned for more inputs when I initially built the controller.

7

Parallel Port breakout boards, motherboards, and dedicated accessories / UC100 Plus PMDX-126 Expanded I/O & PMDX-107

« on: August 22, 2016, 11:30:41 AM »

I'm running a UC100 motion controller and need more inputs.  I've been looking at the PMDX-126 expanded I/O mode but it's not clear if it is compatible with the UC100.  That is, when the PMDX-126 plug in is used in Mach3, will the UC100 pass the extra inputs back to Mach3 and still allow the multiplexed stepper motor PWM signals to work smoothly?  Also, I'd like to use the PMDX-107 for VFD spindle control at the same time.  Is it possible and has PMDX tested this combination of hardware?  Finally, is there a minimum requirement with respect to the step rate on the UC100 when used with PMDX-126 in expanded I/O mode (choices are 25, 50, and 100 KHz)?

Thanks,
Bob