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Plasmamac

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Joined: 31/01/2019
Location: Germany
Posts: 587

Posted: 01:56pm 06 Mar 2023

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Hi , maybe i read it anywhere but forget about because the stroke end Oktober, what size can the picomite handle , what Format should i use? If i put my 16GB sd card in the card is empty even if i put some files before.
Thx

Plasma

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1270

Posted: 02:02pm 06 Mar 2023

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I have a 16 GB Micro SD with ... Fat32 (i think)..
I formated it in windows and it works.

'no comment

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8043

Posted: 02:27pm 06 Mar 2023

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It will work with up to 32GB cards formatted to FAT16 or FAT32.
It uses SPI protocol so all types (Class 4,0,UHS- etc.) are supported.

Mick

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

Plasmamac

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Joined: 31/01/2019
Location: Germany
Posts: 587

Posted: 06:54pm 06 Mar 2023

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My sd card is empty after inserting into the Picomite 🥴
If i eject it the firmware shows the warning. I use the standard option for gpio sd card.
What’s wrong?

Plasma

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10379

Posted: 07:22pm 06 Mar 2023

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Are you looking at the correct drive? SDcard is DRIVE "B:"

type
B:
Files

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9630

Posted: 11:52pm 06 Mar 2023

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Is your card formatted in NTFS?
The PM won't like the taste of an NTFS card.

Smoke makes things work. When the smoke gets out, it stops!

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2679

Posted: 12:45am 07 Mar 2023

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Are you using an SD module with level shifter and regulator ICs on it? They can be a problem on a 3V3 system. Check that you have 3V3 on the SD socket supply pin.

Mark
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Joined: 26/11/2022
Location: United States
Posts: 85

Posted: 09:16pm 07 Mar 2023

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Following up on phil99.

While SD cards are designed to work on 3V3, many of the SDCard adapaters out there are designed to work with 5V microcontrollers, such as the Arduino. As such, they have a level shifter that takes 5V and converts it to 3V3 volts. Since the Pico provides 3V3, if you apply that to the 5V input, the card won't work, or won't work reliably. You need to carefully read the card's documentation to see if it wants 3V3 or 5V. If you are powering your Pico with USB and the card wants 5V, you can power it from the Pico's VBUS line (which is 5V).

Alternatively, other than a possible level converter, all the adapters just provide contacts for the card, there's no other circuitry needed. You can solder wires from the GPIO pins on the Pico directly to the terminals of the SD card. If you have a microSD card with a full size card adapter, solder the wires directly to the terminals on the adapter. That way you have an almost "free" microSD card slot.

Mark

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2679

Posted: 09:25pm 07 Mar 2023

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" you can power it from the Pico's VBUS line (which is 5V)."

That will give the correct voltages on the SD card but may put 5V on the Pico pins. The Pico I/O pins must not exceed 3.6V

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8043

Posted: 09:39pm 07 Mar 2023

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Basically, don't use adapters that have a voltage reg on them. Some will work, some won't. Some will be fine powered from 5V, others have pull-up resistors to 5V and you will be relying on the static protection diodes of the PicoMite to prevent damage. And there may not be any of those diodes (I think the Datasheet only mentions them for ADC inputs).

There are some adapter modules that have simple pull-ups to 3V3 and a decoupling capacitor. Those are fine, I use them myself. There is no voltage reg. Look for a design where the socket is mounted "upside down" on the board.

Mick

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

Plasmamac

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Joined: 31/01/2019
Location: Germany
Posts: 587

Posted: 10:23pm 10 Mar 2023

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The New Sd card works fine. Thx for the help

Plasma

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