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hhtg1968
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Joined: 25/05/2023
Location: Germany
Posts: 123

Posted: 05:35pm 14 Jun 2023

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hello.

a few days ago this forum helps me to connect a sd card reader (5v) to picomite via a level shifter...

now i have bought a 3.3v reader. see tech specs on foto.

but the access is not reliable. the reader is correct connected. sometimes there are no problems, sometimes i get "no sd card found", sometimes i get "hardware problem ... wrong FAT". the files command shows kind of corrupted inventory. i tried to repair the sd card with my computer, but there is the card with no mistakes... back to picomite... and all functions super. one hour later problems again...

if i use the 5v reader there are no problems. perhaps i should send the 3.3v reader back to the dealer...

hhtg1968
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Joined: 25/05/2023
Location: Germany
Posts: 123

Posted: 05:45pm 14 Jun 2023

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hint: i connected the 3.3v to the pin "3v3" on the pico. there is a pin 3v3en (enable?) i am a hardware greenhorn.

i made software for decades. but now i have to occupy with hardware because the picomiteVGA is so exciting for me.

i would be very happy if i can order one (or more) pcbs like from matherp (complete picomitevga)...

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 6798

Posted: 06:14pm 14 Jun 2023

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That uSD card reader seems to have 1k series resistors on the signal lines. It's unlikely to work.

3V3EN is 3V3 ENable - you pull it low to switch off the 3V3 supply. :)

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

Amnesie
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Joined: 30/06/2020
Location: Germany
Posts: 396

Posted: 06:16pm 14 Jun 2023

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If it isn't a contact problem (micro sd-socket ?) I guess the resistor network on the pcb is the problem. If you already use 3v3 you don't need a resistor network at all. Maybe it pulls the voltage down.

Greetings
Daniel

hhtg1968
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Joined: 25/05/2023
Location: Germany
Posts: 123

Posted: 06:30pm 14 Jun 2023

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oh no. forget my question!!!!

i changed the pico an all runs...

to spare about 1 euro i bought picos without headers and i solder them... with the other pico all is right. i think i soldered not so well at the other pico... sorry...

and i think when i changed to the 5v reader i touched the pin and i functions for a while...

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 6798

Posted: 06:31pm 14 Jun 2023

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We have the same problem, but worse, on the SD card socket on ILI9341 displays. Short the resistors in the signal lines out and they are fine. Some cards may work, others won't.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

stanleyella

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Joined: 25/06/2022
Location: United Kingdom
Posts: 2129

Posted: 08:46pm 14 Jun 2023

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Mixtel90 said We have the same problem, but worse, on the SD card socket on ILI9341 displays. Short the resistors in the signal lines out and they are fine. Some cards may work, others won't.

mine all work and ili9488, lucky? the sd card reader is the tidy feature of these displays. neater than a sd card reader and a display.
check wiring and init maybe

vegipete

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Joined: 29/01/2013
Location: Canada
Posts: 1109

Posted: 09:08pm 14 Jun 2023

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Mixtel90 said That uSD card reader seems to have 1k series resistors on the signal lines. It's unlikely to work.

1k series? I see a 10k resistor array, most likely for pull-ups. Might be the one available from here. Unfortunately no circuit diagram is offered.

Visit Vegipete's *Mite Library for cool programs.

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 9129

Posted: 09:23pm 14 Jun 2023

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Just to add to the confusion:

I've found the ILI9341/ILI9488 SDcard slots work fine with a genuine Pico but definitely don't work with the cheap black clones with the USB-C connector. Pretty certain this is a power supply issue.

stanleyella

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Joined: 25/06/2022
Location: United Kingdom
Posts: 2129

Posted: 09:46pm 14 Jun 2023

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matherp said Just to add to the confusion:

I've found the ILI9341/ILI9488 SDcard slots work fine with a genuine Pico but definitely don't work with the cheap black clones with the USB-C connector. Pretty certain this is a power supply issue.

please excuse my dimness but I got a waveshare lcd pico and it's spi so can I use spi2 to use ili9341 instead of the neat inbuilt display? it's usb c that's the point.

Mixtel90

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Posted: 09:58pm 14 Jun 2023

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Sorry Pete - I just checked again. You're right, they are 10k.
In that case it looks rather like the modules that I've been using that I've had no trouble with at all. 10k pullups and 2 supply bypass caps. Mine were just mounted upside down rather than on a 90 degree header.

Strange...

When I had trouble with the ILI9341 I only had official Pico boards, so it wasn't the problem of a clone. I also tried putting caps very close to the socket but that didn't help either. Maybe I was unlucky with the cards / adapters? They were microSD cards that worked fine in a CMM2. :)

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

Volhout
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Joined: 05/03/2018
Location: Netherlands
Posts: 4247

Posted: 05:02am 15 Jun 2023

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Maybe it is the wiring....?
Similar to the 8 color vga problem 1 day earlier

PicomiteVGA PETSCII ROBOTS

andreas

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Joined: 07/12/2020
Location: Germany
Posts: 207

Posted: 08:10am 15 Jun 2023

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These cheap SD-card adapters seem to work ;)
look here

-andreas

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1114

Posted: 08:36am 15 Jun 2023

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andreas said These cheap SD-card adapters seem to work ;)
look here

-andreas

Performed several times. Yes they do

Edited 2023-06-15 18:40 by Martin H.

'no comment

Volhout
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Joined: 05/03/2018
Location: Netherlands
Posts: 4247

Posted: 12:09pm 15 Jun 2023

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Breadboard friendly header...

Connectig jumper wires invisible, under pico and under card adapter.
Just solder 7 right angle 2.54mm header pins to the card adapter...

Edited 2023-06-15 22:11 by Volhout

PicomiteVGA PETSCII ROBOTS

stanleyella

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Joined: 25/06/2022
Location: United Kingdom
Posts: 2129

Posted: 05:52pm 15 Jun 2023

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soldering wires to sd card?!?!

JohnS
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Joined: 18/11/2011
Location: United Kingdom
Posts: 3804

Posted: 06:08pm 15 Jun 2023

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I think it's not - it's to the adapter. You insert the card afterwards.

I like the idea!

John

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 6798

Posted: 06:09pm 15 Jun 2023

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No, it's a micro SD card adapter. It doesn't seem to be labelled in Welsh. ;)
Edited 2023-06-16 04:10 by Mixtel90

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

hhtg1968
Senior Member

Joined: 25/05/2023
Location: Germany
Posts: 123

Posted: 07:14pm 15 Jun 2023

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now i think, why i have ordered a sd card reader? i took an adapter sd to micro sd and soldered it to my platine... so i have a cheap reader for micro cards...

hhtg1968
Senior Member

Joined: 25/05/2023
Location: Germany
Posts: 123

Posted: 07:15pm 15 Jun 2023

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and i hope that it functions...

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