7i92tm + 2xbob

need help with card configuration through pnccfg or mesact...namely specific question can 7i92tm be used without bob  cards directly and if so what is the initial configuration that should be selected in pnccfg? there is an option for gecko in the menu, is it adequate in case of using two bob cards or some other option. so that both P1 and P2 connectors are functional. thanks?

Yes, the G540X2 configuration supports step/dir on both connectors (8 stepgens total)
The 5ABOB x2 configuration is anothe possibility

You _can_ use the output directly with some limitations.

1. They are 3.3V outputs but can drive 5 V  loada when using in sinking mode
( say drive STEP+ to +5V, drive STEP- to  7I92 STEP)

2. The 7I92 pins can be damaged easily by overvoltages (input output range is -0.3V to +7V)
Its very easy to damage with negative voltages unless there is some current limiting

How do you get a negative voltage with high current? Just connect a GPIO pin to frame ground
that has 1VAC of of HF electrical noise relative to 7I92 ground from axis drives/VFDs
If you use the 7I92 GPIO directly, its best to have a small series resistor to protect against
this issue
 

thanks, in that case I like the option to flash the card for 2xbob, both bob via a fmale to fmale 26pin cable?...in that case I need for my lathe machine one spindle analog output, one spindle encoder input and xzA config for servos and two independent simulative mpg wheels for x and z. In that case, will the pnccfg and gecko initial configuration give me the ability to meet the above needs, possibly by modifying hal for mpg and spindle encoder?

Yes, you can use the 5ABOBx2 firmware for the common Sainsmart BOB
and choosing the discover option in pnccconf will allow you to make a
working configuration for that firmware.

On issue with the SainSmart type BOBS is that they have no TTL encoder inputs
Those BOBs have 10v ? sourcing inputs (ground to actuate) which may work with
low resolution encoders with open collector outputs. ( low resolution because those inputs
are fed through slow opto isolators )

This classic bob is available in our market, so in that case, would it be possible to somehow make mpg wheels work with 100ppr/5v?

better solution is always 7i96s, The price of the card is not expensive at all, but the problem is that with customs and transportation, even from Portugal, the price is almost double here in Serbia.

Unless you can get a MPG with open collector outputs ( that match the SainsSmart BOB inputs ),
you are probably better off connecting the MPG  directly to the 7I92.

 

In that case, if I do a mesaflash for two Bobs, will the configuration work using only one Bob as the base, for example the p1 port, and the other port directly from the card?How would you configure it for my case?

You still need to pay customs if you buy from the EU? Didn't that change two decades ago or so?

Anyway - there are cheap clones of the 7i92 on Aliexpress which work the same way like the original, with original Mesa bitfiles. May be worth trying, but they are going more and more expensive very fast. Or does Aliexpress stuff still disappear in Serbian post?

For passive BOBs like the SainSmart ones, the configuration with or without  BOB is Identical