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Aahh shoot! I was hoping to avoid resoldering my DIY pullup resistor board. But thank you for the explanation.

The 7I76EU inputs have a threshold of 60% of VFIELD when going positive and 40% of VFIELD when going negative.
This means with 24V VFIELD, a voltage below 9.6V is read as low and a voltage above 14.4V is read as high.
This  is called hysteresis, and is deliberate behaviour for noise immunity. With a 10 K pullup you end up just in the middle
of this input threshold range, You need a stiffer pullup resistor (say 2.2K) so that you have a valid input to the 7I76EU.

I am pretty sure that you are correct, at least in the part about the inputs being reversed between the two boards.
But it is my understanding that this is why the pull-up resistor is needed, so that the input at idle is 12v and then when activated goes to 0. So to get the correct logic in linuxcnc I use the xxx-not input signal.

But I don't understand why the hal state doesn't change after the first trigger, even though I can see the voltage change on the input pin.

Wait until  someone else confirms but I think your issue is that the  Mach3 board senses on the negative side and the 7i76e senses on the positive side. In other words on the 7i76e, you need to switch the input to +24 volts not GND

Read page 24 of the Mesa manual.

Hi,

I am trying to convert my DMC2 Mini from the chinese Mach3 board it came with, to LinuxCNC via a Mesa 7i76eu. And I have most of it working by now But I am having an issue with two simple inputs.

I have two probes, a hight pug and a xy probe, that basically just connects to GND when triggered. They are connected to the mesa with a 10kOhm pull up resistor. This is what I am seeing when I power the machine on:
- The input pin on the Mesa card reads 12v and the input is as expected high/true in hal show
- I then trigger the probe and the input pin now reads 0v, and the input is low/false in hal show
- After I "release" the probe the input pin returns to 12v, BUT the input remains low/false in hal show

Any ideas why the input in hal doesnt return to high when the pin reads 12v with a multimeter
Field power is 24v, and all voltage readings are done between field GND and the input pin.

Thanks in advance

net joint.X.amp-fault-in hm2_7i76e.0.7i76.0.0.input-16-not
etc...

Do U replace this section
# HLFB is true when enabled *and* following
net hlfb_x  hm2_7i76e.0.7i76.0.0.input-16-not 
net hlfb_y  hm2_7i76e.0.7i76.0.0.input-17-not
net hlfb_y2 hm2_7i76e.0.7i76.0.0.input-18-not
net hlfb_z  hm2_7i76e.0.7i76.0.0.input-19-not
net hlfb-a  hm2_7i76e.0.7i76.0.0.input-20-not

With net joint.X.amp-fault-in whatever_input_pin

? Thanks 

Just as a general thought, no GUI configurator can fully support the 7I76EU
(or any other hardware) , though I think MesaCT does support the output options.

In all but the simplest cases, some hand editing of hal/ini files is likely to be needed
and considerable hal customization will be needed for functions like tool changers,
spindle orientation, jogging options etc etc.

Thanks a lot for this information. Currently I will stay with the sourcing Outputs. I just started with LinuxCNC and don't plan to modify the Hal-File by hand at the moment (Pncconf is currently my approach).
If I'm more experienced with LinuxCNC I will do this modification or maybe a new LinuxCNC version is available which fully supports the 7i76EU.

pncconf does not know about the field output options of the 7I76EU
(it only knows about the 7I76E)

The 7I76EU  has individually settable output modes for each output.

The default setting is sourcing mode on all outputs.

Sourcing mode means the 7I76EU outputs supply positive field voltage to a ground referred load
This is identical to the original 7I76E.

To set up sinking or push-pull outputs you must set the source or sink
parameters. These parameters are 16 bit numbers where each bit determines
the output mode of a single output. Bit 0 in the source and sink parameters
control the operation of output 0 and so on.

The default setting is source = 0xFFFF and sink = 0x0000 meaning all outputs are set to
sourcing mode.

To set to sinking mode, you set the desired sink bit to 1 and the corresponding source bit to 0
 To set push-pull mode, you set both the sink and source bits for the corresponding output.

That is if you wanted the first 8 outputs (0..7)  to be sourcing and the last 8 outputs (8..15) to be sinking
you would set the source parameter to 0x00FF and the sink parameter to 0xFF00

This is described on page 17 of the 7I76EU manual

Note the these parameters cannot be set dynamically, they must be set with setp commands in the hal file.

 

Die Eingänge laufen bei mir wie gewünscht, leider bekomme ich die Ausgänge nicht in Betrieb. Ich möchte gegen Gnd schalten, passieren tut nichts

Nachtrag: Verdrahte ich Output 0 auf TP6 als Schalter gegen + 24V (d.h. die Last liegt auf der anderen Seite an Masse) dann funktioniert es. Ich dachte die 7i76EU hat Universal Outputs, d.h. kann beide Modis?

I fixed the missing 7i76eu from the stepper boards variable which caused a partial build of the main.hal file and leaving out the enable and the stepper setp lines.

JT

Can you attach your ini file?

Did you skip Drive 0 and Drive 1?

JT

Gerne, aber ich bin noch nicht sicher ober der Parameter "7i76 Modus 2 I/O card" so richtig gesetzt ist oder ob ich Linux doch noch auf "UTF-8 EN_US" umstellen muss.
Nachtrag: Zumindest funktionieren jetzt die Endschalter (kann den Status in LinuxCNC richtig sehen, die Schalter ändern sich auch

Hallo Raspll,
danke für deinen Post! Jetzt wird mir einiges klarer.
Ich arbeite mich gerade durch das Handbuch um HAL und INI händisch anzupassen.
Genau aus dem von dir beschriebenen Grund.