6i25 + 7i76 plug and play, card not showing and no tabs in pncconf.

I guess the answer is that I should only use step+.

Looking at the high speed wiring in the previous diagram I see a 100 ohm short circuiting resistor I do not like.
5 Volt over 100 ohm is 50 mA. In the 7i76 manual I read that the 5 V step/dir signals can drive 24 mA.
Conclusion would be that I cannot use the high speed wiring.
But in the Delta servo manual there is also information saying that the high speed signal's forward specification is <25 mA, see attached picture.
What is "forward specification"?
I must ask Delta support to clarify this contradiction.
Can you say anything about what is the correct/safe way to proceed?

Best regards
Patrik

Differential mode is generally better, so:

You could use a Ohmmeter to see if the input termination is actually 100 ohms
Often high speed inputs use AC termination (100 ohms in series with a small capacitor)

The 7I76 outputs will drive AC terminated inputs without issue

If the inputs are actually 100 Ohm DC terminated, you could add a 50 Ohm series resistor
to one of the 7I76's outputs to limit the output current to <24 mA
(the 7i76 outputs already have ~75 Ohms differential output impedance)

Thanks
I measured the input to 220 ohm. It seems it is not AC terminated since the ohmmeter shows a steady 220 ohm.
This means it will draw 23 mA when 5 V is applied.

In single sided mode it ill draw 23 mA only when the pulse is high. In differential mode it will draw 23 mA always, right?
Do you recommend I use differential mode (both step+ and step-)?

BTW, just because I want to learn.
If the 7i76 step output has a 75 ohm impedance, does that mean that the 5 V is inside those 75 ohm and that the ouput from the 7i76 will be only 4 V when connected to a 300 ohm load?

BTW, just because I want to learn.
If the 7i76 step output has a 75 ohm impedance, does that mean that the 5 V is inside those 75 ohm and that the ouput from the 7i76 will be only 4 V when connected to a 300 ohm load?

Yes that's correct

No driver has 0 output impedance so if you have a 5V power source the load voltage will always be less then
5V if the load has non infinite impedance.

The 7I76 outputs have added series resistance to protect them from short circuits.
This and the internal driver impedance add up to ~75 Ohms differential

I would always choose differential mode when possible as it has much better noise immunity

This post is just to say thank you for the excellent support, and for an excellent product. So far I am very happy with my Mesa cards.