Spent some time investigating with other devices today.
Configured a Pi Hat SH1106 4wire SPI device via Software SPI and found a stable config.
Moved pins around to be Hardware SPI and the display and TMC did not function.
Besides the MKS Mini display being a uc1701 chip and the Pi Hat being SH1106, the MKS mini display has a 4050 buffer ship on the in bound SPI to the Display and SD lines.
I started digging into SPI lengths, etc, and only discovered that, in theory, this “should” work.
Did more research and finally found this: TMC2130 & UC1701 issue · Issue #1208 · Klipper3d/klipper · GitHub
Now I did check github, but did not run across this specific case. I was looking for “st7567” and “MKS Mini” in my previous searches. This time I did a internet search for: uc1701 spi speed and found the above Klipper issue.
This issue noted that adding spi_speed: 4000000 to each SPI location (TMC and Display), all devices on he bus work together.
Made the change and indeed, all 5 TMC’s and the display are functioning on the same Hardware SPI bus.
The SH1106 display also needs spi_speed: 4000000 in the .cfg.
Not sure if here are any con’s yet, or if the issue was the display was setting one speed that the TMC’s didn’t like?