Editing Bitfile on 7i97t for extra smart serial connections

Hello,

moving along in my retrofit I got all 3 axis, the spindle and also the 3 jog handwheels to run on my machine using a 7i97t and a 7i84d connected to the standard smart serial output. Now I want to add a 7i73 in the control panel to connect all my physical buttons and encoders on the control. For that card I need an additional smart serial channel which the standard 7i97t does not have.
I was told in an earlier post that I can edit the bitfile on the 7i97 to add rx and tx pins to the unused expansion port. I have already made an convertor board to take these signals and convert them to smart serial as shown by talla83 in this video.

to use these 2 additional channels the bitfile needs to be modified to have 4 pins on the P2 expansion connector give 2 rx and tx signals each.

My question is how to do that since the manual of the 7i97 informs me that loading wrong bitfiles will brick the card.
What steps do I need to follow?

You could use  7I97T firmware for a 7I85 configuration. This includes
5 additional channels worth of sserial interfaces:

7i97t_7i85d.bin

 

Ok is that something that is already on the card and just needs to be activated? Will the other Pins retain their functions (does this only change the expansion connector)?

Thank you for the quick reply

You install 7i97t_7i85d.bin firmware on the 7I97T and
the definition of the P1 pins changes.

(In the default firmware: 7i97t_7i85d.pin, all P1 pins are GPIO)

Okay that sounds like less hassle than editing bitfiles. How can I install this different firmware and where can i get it?

www.mesanet.com/software/parallel/7i97t.zip
 (in 7i97t/configs/hostmot2)

You use mesaflash to update the firmware, examples of mesaflash usage
should be in the 7I97T manual

Thank you so much I will try it tomorrow.

Ok so I have flashed the other firmware to the card and that seems to have worked. When I use the readhmid command it shows RX/TX pins on the expansion connector.
Now I need to connect the smart serial adapter board to these pins and to my 7i73. That does not work currently. I want to rule out the easiest mistakes first. I am not sure of the pinout of the expansion connector on the 7i97. I can see what pin is rx/tx in the terminal with readhmid but I'm not sure where the physical pin on the 7i97t is.

Can someone clarify that?

Open 7i97t_7i85d.pin in a text editor. This has the relationship between signals & connector pins.

Just to be clear the "bit files" can't be edited (by normal humans), bit files need to be generated by using the tools provided by FPGA manufacturer (like compiling soucre to an executable). Not for the faint of heart.

I already have the correct bitfile on the card. My question is where the physical pin on the card is located.
when the bitfile says expansion port Pin 1 where is it on the expansion connector on the card.