problem with paralel port pin 10 running onpdmx 126 with mach3

[don_gift]

First , my english is not accurate , as i?m Brazilian. sorry about that.
i have a cnc machine ( router with servo motors ) driven by a PMDX 126 .
the estop function is working fine : when emergency button is pressed the mach 3 resets and turn to off line, and whwn i turn off the machine the same occurs .
But when  turn off the pmdx after a established connection f  , , clicking the reset button on mach 3 it lights and appears to be on line , virtually.
i checked the voltage on pin 10 and notice that after turned off the pmdx doesn't reset the 5v that comes from the pc parallel port in order to doesn't let the mach 3 turn on line . Only if i turn off the pc or disconnect  and reconnect the parallel cable mach3 returns to know that the pmdx is out of service and the voltage becomes 5 V again . ( that voltage is generate t from pc?s parallels port  - of course )
with the mach 3 and pmdx connected and working fine this voltage is about 0v . After a cnc  power down it doesn?t returns to 5 v . the tension is about 1,30V vdc witch is sufficient to mach 3 think that the system is on line .
there is a capacitor and resistor between the pin and his way to the Ci ( i think it is the parallel controller. is any possibility that this capacitor is out of range and grounded after the first connection ?
 tks

Don

[Steve Stallings]

I am not sure that I understand your description.

If you are measuring the voltage of pin 10 of the parallel port itself,
then things do not seem normal.

The PMDX-126 will drive pin 10 to a logic low (less than 0.8 volts)
when the PMDX-126 has power and there is NOT an E-Stop condition.

It will drive pin 10 to a logic high (greater than 3 volts) when the
PMDX-126 has power and there IS an E-Stop condition.

When the PMDX-126 does not have power, it will let pin 10 float and
the parallel port in the computer will pull the pin to a logic high and
Mach will see an E-Stop.

The Mach software should be configured for pin 10 to be active High
(a red X in the selection column labeled Active Low).

It may be possible that your parallel port does not pull the signal to
a logic High when the PMDX-126 lets the signal float. It is safe to
add a resistor from pin 10 of the parallel port to +5 or +3.3 volts
from the computer.  One place that you can get +5 volts is from an
unused USB jack. If your parallel port is on a plug in card, you may
be able to add a resistor to the back side of the card.

[Bob at PMDX]

What revision of PMDX-126 do you have?  This is written on the board just above the serial number block.  On Rev B and Rev C boards, this is in the corner of the board next to the parallel port connector.  On Rev A boards, this is near the EStop LED.  The revision will be a letter followed by a number.  For example, "C2", "B1", etc.

Bob