7i92/G540/C10/THCAD

crowloy wrote:

my understanding is that the G540 is not really a great device to use for the encoder due to slow response as well as incompatiblility with the G540 input voltage from what I've been reading. A good reason to switch it over to the C10 on P1. My G540 is an older unit bought when I made my first CNC back in 2015 or so. The C10 is a new style board with surface mount components

So how do you specify an encoder on the P1 port? In your HAL you specify that you have an encoder, but the default is encoder 0 which happens to be on P2. I don't see an option on the loadrt hm2_eth to say you want an encoder on another port or for that matter in hostmot2.

The 7i92 is configured with G540x2 bitfile. The G540 bit is close enough to the C10 i/o that there is not much differance. Also one thing I've noticed and so far have not been able to change is that when linuxcnc is not running, the outputs on P1 seem to be high. I've got a cheap chinese relay board hooked up to the C10 on 2,3,4,5 pins. They are all active until linuxcnc runs and setp's the gpio to output. Only then do they turn off and control of them can occur.

To get access to the second encoder you set "num_encoders=2" in the
hm2_eth command line, the second encoder will be encoder 01

The 7I92 outputs are high at start-up (all pins are inputs at start-up and all inputs have pullup resistors) So its better to arrange for active low inputs if possible or have a common active low output that controls relay power or relay board +5V