[solved] Need help with RV901T as MESA 7i90: SPI isn't working

SI stands for Signal Integrity

Note that adding the logic analyser
(if it does not have resistors in the actual probe clips)
will cause major SI issues by itself

You might try with the LA disconnected
Another possibility is adding a series termination
resistor to the clock line source end (say 47 Ohm)

Cant do this anymore bye all wrote:

Did you change the values for he DCM sections to take into account the 25MHz clock ?

I just looked at my sources...

Hello cornholio,

I would be grateful if you could share your sources for 7i81. I will try to compare with the original to doublecheck the places I have changed already.

I think I recall you were powering the board from 3.5v I’d check the output from the voltage regs, just to make sure everything is as it should be.

I noticed that in your card file you changed the clock values from constants to integer values, that wasn’t needed, neither was changing the card name values, but that should be neither here nor there.

For some reason I can’t find the SPI sources for the rv901t, tho I do have EPP but These are for 7c81 as my poor board has a couple of issues with the knuckle dragger who desoldered 2 chips, yeah a broken track per chip.

At this stage it might well worth loading a led flasher type bitstream just to confirm operation of the board.

Also Pete’s suggestion about disconnecting the logic analyser would be an idea. All I used was a multimeter just to check that the power rails were good.

With clocks 8 has to become 16 and 4 has to become 8, so there’s only 2 values to change.

During my experiments I was only using a single GND. Mesaflash worked fine, but wasn’t so great when communicating with the driver, I had to limit the clock speed.

Guys, thanks a lot! Looks like there was my bad with the not very qualified soldering. I desoldered all the pads and cleaned the mask from them. Then returned all back and it start working! even with analyzer.

Still had to find the place of checking the crystal in mesaflash to avoid this:
But this is the minor thing. Thanks again!
Added [solved] to header!

Sorry, removed [solved] for a while...

ago_tm wrote:

Code:

sudo ./mesaflash --device 7i90 --spi --addr /dev/spidev0.0 --fallback --write ~/Downloads/topgcspihostmot2.bit Checking file... OK File type: Xilinx bit file Error: wrong bitfile destination device: 6slx16ftg256, should be 6slx9tqg144 But this is the minor thing. Thanks again!

Hmmm... I easily changed the following line but now I faced with the BootBlock...
Is it possible to write the fallback bitstream to the flash using mesaflash in my case?

what does:

sudo ./mesaflash --device 7i90 --spi --addr /dev/spidev0.0 --verbose

report?