[fixed in 0.95 ?] preenfm3 sd card error

[lokki]

hi xavier,

i flashed the firmware successfully.

unfortunately my LCD was a different kind of pcb, but still 2.8''. the holes for the sdcard-reader don't align. i bent some headers and soldered it, but maybe something is wrong...it is also possible the reader does not work on the PCB, it is a cheap chinese LCD. the screen itself works flawless.

now,
-when i boot up without an sdcard inserted i get a: SD CARD ERROR after which the preenfm3 boots successfully.
-when i insert a sdcard at boot up, the screen just stays black. if i then unplug the sdcard, the screen goes white
-when i insert a sdcard after boot up the screen goes black. when i remove it the screen goes white.

does that indicate anything?

if i would attach a separate sdcard reader module, i need the four connections and 3.3v and gnd?

[Xavier]

Hi,

I just replied to the other thread to flash the firmware, glad you could flash it.

Can you let me know the exact TFT you have.
I didn't know some of them have different SD pins.
What are the 4 SD pins label on the TFT ?
Maybe some of them does not correspond to what the preenfm3 expect.

[lokki]

sorry, yes i realised the "x" thing after a while as well, had no time to post it yet.

this is the link to the display:

https://www.aliexpress.com/item/4001135326039.html?spm=a2g0s.9042311.0.0.27424c4dP0cOvE

the sd pins seem to align, no?

is there anything more verbose in regard to the sdcard that i could try?

[Xavier]

It's difficult to get any info from the SD card other than it does no work.

-when i boot up without an sdcard inserted i get a: SD CARD ERROR after which the preenfm3 boots successfully.

OK that's expected.

-when i insert a sdcard at boot up, the screen just stays black. if i then unplug the sdcard, the screen goes white

Seems like it stays locked while trying to initialize the SD driver (or read from the card).
Does your SD card contain the /pfm3/ folder ?

If yes can you try to reformat it (fat32) and copy the /pfm3/ folder again on it.

[lokki]

it seems i am missing some fundamental stuff :-) 

will copy the folder to the sdcard (did not know i had to do that) the wiki does not mention it, no?
i guess i have to look at the zip file.

[lokki]

sorry, i only looked at the 0.91 release, and it didn't contain the sdcard zip file...found it in the 0.90 folder.

[Xavier]

You're right the SD wiki part is still missing. Sorry.
Yes the zip is attached in the v0.90 release :
https://github.com/Ixox/preenfm3/releases

[lokki]

hmm, the screen still stays black even with the folder on the sdcard...

will try a different sdcard. or maybe the reader is really broken on the screen

[lokki]

and another sdcard does not fix this...

but, the blue led on the main pcb blinks, even when the screen stays black, maybe that tells you something?

can i just attach another microsd card modul with SPI and 3.3v logic?

[Xavier]

but, the blue led on the main pcb blinks, even when the screen stays black, maybe that tells you something?

Interesting, it means the pfm3 firmware is correctly running but the TFT is not.
I don't understand how puting a SD card can prevent the TFT to run...

Is the TFT totally black (no led at all), or black (with backlight) ?
There's a way to reinit TFT, can you try :
. v0.90 : holding the MENU 2 or 3 seconds
. V0.91: Hold down MENU (7) + press previous instrument (8 ) (see buttons number here)
What is the result ?

can i just attach another microsd card modul with SPI and 3.3v logic?

Yes, it should work if you follow the SPI pins.
But i'm still not sure your SD card does not work.

[lokki]

it is totally black (no backlight), as soon as i put in the sdcard. and as soon as i take it out it goes all white.
pressing menu does not help it stays white (i am on 0.90 now but will update again to 0.91 and try as well)

[lokki]

Got it working. As I suspected it was the sdreader on that display module that was faulty. For testing I simply soldered a SD to micro sd adapter to the corresponding PINs on the preenfm3,since I found out that sd cards are directly SPI compatible...

Guess my preenfm3 will be accepting microSD from now on

[Xavier]

Got it working. As I suspected it was the sdreader on that display module that was faulty. For testing I simply soldered a SD to micro sd adapter to the corresponding PINs on the preenfm3,since I found out that sd cards are directly SPI compatible...

Guess my preenfm3 will be accepting microSD from now on

Great 
and thanks for the update

[Olivier]

When working with firmware 0.91 I can't get the SDCard to work from the sreen, so I installed a new SDcard reader, but it doesn't work.

I look at https://github.com/Ixox/preenfm3/issues/3, install firmware 0.90 and now  the new SDcard reader work fine.
I didn't try the SDCard reader from the sreen.

[Xavier]

Thanks for pointing the github issue, i missed it.

As i wrote in the issue :
"0.91 use DMA to send and receive data from the SD Card.
I don't know why it does not work with your SDCard.
What sdcard do you use ?"