Mesa 7i96 and LinuxCNC 2.8 PnCConf

Do the 7I96 input LEDs illuminate?

If not, you likely have a wiring error

(is input common connected to your power supply common?)

LED's are not illuminated so it is my wiring. Am I supposed to run a wire from my PSU ground to the TB3 common (pin12)? I'm going to check out the manual again.

Went through to forums and found this. Thank you!

PCW wrote: The 7I96 isolated inputs have a single common pin.

If you have 5V signaling and your switch common is connected to +5V you should connect the 7I96 input common pin to ground, then when a switch is closed (and 5V applied to the input pin)
the corresponding GPIO bit should read high

If you have 5V signaling and your switch common is ground, you should connect the 7I96's input common to +5V
then when a switch is closed (and the 7I96 input pin grounded) the corresponding GPIO bit should read high

You can use the "watch" command in axis to look at the GPIO pins in real time

(is input common connected to your power supply common?)

The input connections and characteristics are in the 7I96 manual:

ISOLATED I/O
The 7I96 has 11 isolated inputs and 6 isolated outputs. All 11 Isolated inputs have
a common pin. This common pin must be connected to ground for active high inputs and
connected to the I/O power for active low inputs. The 6 isolated outputs are completely
floating switches so can be used for pull-up/pull-down and mixed voltage switching.

ISOLATED INPUT CHARACTERISTICS
The isolated inputs use opto-isolators with a 4.7K input series resistance. This
results in an approximate current draw of 5 mA at 24V. The inputs will operate with +-3V
to +-36V signals relative to input common. Isolated inputs are relatively slow and not suited
for signals faster than about 5 KHz. For sinking type inputs, the input common pin is
grounded and a +3 to +36V signal is applied to the input pins to activate the input. For
sourcing type inputs, the input common is connected to +5 to +36V and the input pins are
grounded to activate an input.


I will add the default GPIO mapping of the inputs to the manual

I have rewired my TB3 header and now have lit up almost all of the LED's on the isolated inputs. I also changed my limit switches in HAL to reflect the proper GPIO pin# (0-5).

I grounded off the common pin(11) to my PSU ground, with +24v into the limit switches. I've attached a picture of the pin LEDs, the bright ones are to my relay, the rest are faint (some unlit are to my THC) and one is not lit up at all. Weird. I'm going to see if I can remedy this with wiring.

HOWEVER, I pulled up halshow and halscope and I was not able to actuate any of my limit switches... I'm completely at a loss as to why that is. I'm currently swapping from 10 to linux because my network card doesn't like linux. I'll grab my newest HAL/INI and post them here for you to check out.

Looks like you have pairs of LEDs lit,

This means you are just looking at AC noise.

Perhaps you don't really have the 24V common connected to the 7I96 input common, (pin 12) just frame ground or something similar.

If you have a voltmeter you should be able to read 24V from the 7I96 input to the input common pin, (when your limit switches are on) if not, there's still a wiring error.