PanelDue SD card not working

dc42

The PanelDue firmware version doesn't matter, because the SD card on the PanelDue display is connected directly to the Duet via the ribbon cable.

How long is the ribbon cable? Can you read the SD card in a PC, and if so, what is its capacity and what disk format is it using?

Eduma

Ribbon cable is 50cm long. SD card reads in PC. I place gcode file in root and in a "gcodes" folder.

4gb, fat32

elmoret

50cm is pretty long, much over 30cm doesn't work well due to signal issues.

Eduma

I thought I read that a 40cm and 80cm were tested. With 40cm working and 80cm not? Is this the typical response if the ribbon cable is too long?

dc42

@eduma said in PanelDue SD card not working:

I thought I read that a 40cm and 80cm were tested. With 40cm working and 80cm not? Is this the typical response if the ribbon cable is too long?

Yes, it the cable is too long then the SPI signals don't get through without being corrupted and the card can't be read. Not all ribbon cables are the same, and some allow longer runs than others.

Eduma

@dc42

I appreciate the prompt response. I'll have to try a larger gauge cable or look into a break out board that I can mount closer to the controller.

Eduma

I went ahead an built a custom cable using 24 gauge wire and still receive the same error. Does anyone have any other thoughts. Or is an SD card breakout board my only option. Unfortunately i can't move the display any closer to the controller.

elmoret

Its not the thickness of the wire, it is interference, both from the signals in the wires themselves, and external sources.

Minimizing those will help you, but may not guarantee success.

dc42

And the capacitance too.

I suggest you try it with a much shorter cable, to confirm that the SD card and socket are working.

DennisHall

I have this same issue using the Duet3D supplied ribbon cable.
In my case, the SD Card in my 7 inch PanelDue is not recognized - ie. I don't even have a visual indicator on the LCD that there is an SD Card reader installed.

Could this be due to my firmware version 2.01(RTOS) (2018-07-26b2)?
I have the PanelDue connected up correctly and everything works fine except the SD Card not being seen at all.

One Note, I also only see (what looks like) 8-bit colors and the screen resolution is very low (very pixelated).

If I run the board and LCD off my proven PSU with nothing else connected, the symptoms don't change.

Any ideas what could be the issues?

dc42

Firmware 2.01 should be able to access the second SD card. To access it you need to mount it, either explicitly by sending M21 P1 or implicitly by changing to the second SD card in the DWC or PanelDue file list page.

Bad colours on a 7 inch non-integrated PanelDue usually mean that the firmware for a 5" screen or an integrated 7 inch screen has been installed. Recent versions of PanelDue firmware have red, green and blue colour gradients on the Setup page, to help you check that the colours are correct.