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Rickard5

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Joined: 31/03/2022
Location: United States
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Posted: 01:20am 06 Apr 2022

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I'm building a Picomite 1.3 and was wondering will this
https://www.amazon.com/Interface-Arduino-Raspberry-Breakout-Cable?Pack/dp/B07MTTLF75/ref=sr_1_6?crid=1SXHR3V92GOLE&keywords=Adafruit+Micro+SD+SPI+or+SDIO+Card+Breakout+Board+-+3V+ONLY&qid=1649175936&sprefix=adafruit+micro+sd+spi+or+sdio+card+breakout+board+-+3v+only+%2Caps%2C129&sr=8-6

work in place of the $9 Adafruit Micro SD SPI or SDIO Card Breakout Board - 3V ONLY ?
Thanks

I may be Vulgar, but , while I'm poor, I'm Industrious, Honest, and trustworthy! I Know my Place

lizby
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Joined: 17/05/2016
Location: United States
Posts: 3480

Posted: 01:30am 06 Apr 2022

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That will +probably+ work. Some alternative micro SD modules have caused problems--sometimes because of unneeded/inappropriate resistors.

Note that when copying a link, you only need the part up to the "?" (not including it). Also, it's generally better to use the link icon (4th from left above text box, globe with 2 chain links icon).

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

al18
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Joined: 06/07/2019
Location: United States
Posts: 231

Posted: 03:19am 06 Apr 2022

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FYI the Adafruit Micro SD SPI or SDIO Card Breakout Board - 3V ONLY! is only $2.95, but I see they are out of stock. Mouser has this board in stock at $2.95. Note the Adafruit board has 9 holes on the edge of the board, but the PicoMite VGA only has connections for 6 holes.

I didn�t find an alternate on Amazon.com. Most on Amazon have a voltage regulator and are designed to work at 5v - not compatible with the Pico.
Edited 2022-04-06 13:23 by al18

Rickard5

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Posted: 03:52am 06 Apr 2022

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al18 said Mouser has this board in stock at $2.95. Note the Adafruit board has 9 holes on the edge of the board, but the PicoMite VGA only has connections for 6 holes.

Thanks AL Cool thing is we have a Mouser warehouse 20 min from here :) I'm hoping to go to WILL CALL IN the morning :)

I may be Vulgar, but , while I'm poor, I'm Industrious, Honest, and trustworthy! I Know my Place

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2832

Posted: 04:27am 06 Apr 2022

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" Most on Amazon have a voltage regulator and are designed to work at 5v - not compatible with the Pico"

My experience is that when these 5V units are connected to a PicoMite (or any MicroMite) and powered from 3.3V they will work with most SD cards. The regulators used are low dropout types and with 3.3V in you get 3.0V out. Most SD cards can work down to 2.7 or 2.8V. If you do have a problem just bridge the regulator.
Edited 2022-04-06 14:28 by phil99

Amnesie
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Joined: 30/06/2020
Location: Germany
Posts: 719

Posted: 10:44am 06 Apr 2022

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I use the blue adafruit sd board with the 5V option and tested both, the 3V3 and 5V. Both voltages work without any problems. I decided for the blue (5V ready) version because the black 3v only is out of stock everywhere in europe. Same goes with the LDO voltage regulator and voltage reference, but no problem since I made up my own PCB to fit available parts and pinouts.

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8298

Posted: 05:30pm 06 Apr 2022

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These are good - they include pull-up resistors and a supply decoupling cap. It would be better to get the correct unit to fit the main PCB though.

Mick

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

al18
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Joined: 06/07/2019
Location: United States
Posts: 231

Posted: 05:49pm 06 Apr 2022

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Mick, the pinout on the eBay MicroSD board is different than the Adafruit 3.3v MicroSD board.

Mixtel90

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Posted: 06:00pm 06 Apr 2022

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As I expected - that's why I'd recommend getting the right module. If it came to the correct board being unavailable, though, I'd rather sticky pad one of these down and hard wire it than use one that may or may not work.

Mick

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

Pluto
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Joined: 09/06/2017
Location: Finland
Posts: 398

Posted: 08:10pm 06 Apr 2022

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I have used these ones. Satisfied sofar with functionality & price. If you order e.g. 10, the freight is reasonable per unit. ($5.60 + freight $1.56 for 10pcs.) Delivery time 1 month.

Https://www.aliexpress.com/item/32867572635.html

No regulators onboard, only 10k pull-up resistors on signal lines. I have them directly connected to PicoMite's 3.3V. (Without serial resistor on 3.3V. No bypass capacitor added.)

Pinout:
3.3V
CS
MOSI
CLK
MISO
GND

/Fred

Mixtel90

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Joined: 05/10/2019
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Posts: 8298

Posted: 08:21pm 06 Apr 2022

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Those look like the same as the link that I posted, but without the header soldered on. :) There are 4x 10k pull-ups and two capacitors in parallel. They add up to about 33uF IIRC. I've used them a couple of times now.

Mick

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

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