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matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10629

Posted: 08:22am 27 Jan 2023

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https://www.aliexpress.com/item/1005004917998963.html?spm=a2g0o.cart.0.0.5b8c452cTCP9jC&mp=1&gatewayAdapt=glo2pol

Features: USB-C connector, 16MB flash, reset button, better voltage regulator, 100% pin-to-pin match, USB-cable included. Currently GBP3.44 each (4-off) including shipping

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8304

Posted: 09:06am 27 Jan 2023

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That looks like a very useful version, especially as it will surface mount. I wonder if the VR will actually pass 500mA or whether there isn't enough heatsink area? :)

Mick

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

Solar Mike
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Joined: 08/02/2015
Location: New Zealand
Posts: 1174

Posted: 09:27am 27 Jan 2023

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I looked at those, unfortunately the CPU ADC reference pin is hard wired to the 3.3v bus instead of the external Ref input, which appears to be wired incorrectly.
See schematic here Link

Cheers
Mike
Edited 2023-01-27 19:38 by Solar Mike

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8304

Posted: 03:12pm 27 Jan 2023

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I suppose it could be a drawing error - VREF isn't going to do much if it's right, is it? Having the reference fixed at 3V3 from a linear regulator isn't as much of a problem as having the VREF pin messed up IMHO.

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: 2681

Posted: 03:29pm 27 Jan 2023

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Cheap as chips.. don't ask for fish. picomite clones. Very cheap hobby is mmbasic now.

Cyber

Senior Member

Joined: 13/01/2019
Location: Ukraine
Posts: 161

Posted: 06:40am 31 Jan 2023

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There are more of them: https://www.aliexpress.com/item/1005003928558306.html
There ara many, and they all look different.
Should all of them be able to run PicoMite firmware as is?
Edited 2023-01-31 16:42 by Cyber

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2833

Posted: 07:14am 31 Jan 2023

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I have the purple 16MB Type-C It runs PicoMite Basic just the same but:-

At 378MHz runs 10C warmer than an original
The pin sequence is different to bring out more I/O but can not be plugged in to existing PCBs.
When GP0 is DOUT it won't pull down, needing a resistor to ground.
That might be just the one I have, or they may be using rejects.

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8304

Posted: 08:50am 31 Jan 2023

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It's safe to assume that NO Pico copies will be 100% compatible. If you must have a bigger flash area AND have guaranteed IO pins/compatibility then wait for the next official version or two. :) In the meantime prepare to compromise or work round things.

Mick

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

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