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pwillard
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Joined: 07/06/2022
Location: United States
Posts: 337

Posted: 07:16pm 02 Jan 2026

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Trying new version 6 firmware on my old RP2040.

Now I'm confused.

Using the MANUAL example:

SETPIN GP21, DOUT
DO
PIN(GP21) = 1
PAUSE 300
PIN(GP21) = 0
PAUSE 300
LOOP

I get blinking on GPIO pin 16

Using this code:

SETPIN GP16, DOUT

DO
PIN(16) = 1
PAUSE 100
PIN(16) = 0
PAUSE 100
LOOP

I get fast blinking on pin 12.

???

lizby
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Joined: 17/05/2016
Location: United States
Posts: 3618

Posted: 07:29pm 02 Jan 2026

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Pin(16) is GP12. You must use either the pin numbers or the GP numbers--they aren't the same.

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

pwillard
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Joined: 07/06/2022
Location: United States
Posts: 337

Posted: 07:31pm 02 Jan 2026

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I think I forgot that... its been a while.

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 8568

Posted: 08:14am 03 Jan 2026

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Please don't use hardware pin numbers at all if you can avoid it. Doing so can completely screw up compatibility between your software and different hardware platforms. :( The chip itself uses the GPIOxx format, which MMBasic kindly abbreviates to GPxx to save our poor fingers, the I and O keys.

Mick

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Canada_Cold
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Joined: 11/01/2020
Location: Canada
Posts: 52

Posted: 12:31pm 09 Jan 2026

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Hi,

Regarding using GPxx numbers rather than pin numbers, is there a way to address the GPxx as a variable?

In the following code snippet I used the pin number;

DIM INTEGER PINOUT
PINOUT = 14 ' GPIO10
SETPIN PINOUT, DOUT
PIN(PINOUT) = 0 ' Pinout = low

Is there a better way to do this?

Don

Volhout
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Joined: 05/03/2018
Location: Netherlands
Posts: 5703

Posted: 12:40pm 09 Jan 2026

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Hi Don,

there is a way using pin numbers derived from GPxx.

CONST pinout=MM.INFO(PINNO GP10) 'there is a number associated to GP10
SETPIN pinout,DOUT
PIN(pinout)=0

Why is this better ? Simply because pin 14 is connected to GP10 in a genuine RP pico, but in a different board it could be on a different pin (i.e. 16). And GP10 is universal.

Volhout
Edited 2026-01-09 22:50 by Volhout

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Canada_Cold
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Joined: 11/01/2020
Location: Canada
Posts: 52

Posted: 03:15pm 09 Jan 2026

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Hi Volhout,

Thank you for your post and the code example. I hadn’t considered that the pin numbering might be different on non RP boards. It certainly makes good coding to use the GP numbers. I’ll have to implement this in my code now.

Thanks again, Don

homa

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Joined: 05/11/2021
Location: Germany
Posts: 539

Posted: 05:42pm 09 Jan 2026

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Volhout said
there is a way using pin numbers derived from GPxx.

CONST pinout=MM.INFO(PINNO GP10) 'there is a number associated to GP10
SETPIN pinout,DOUT
PIN(pinout)=0

Why is this better ? Simply because pin 14 is connected to GP10 in a genuine RP pico, but in a different board it could be on a different pin (i.e. 16). And GP10 is universal.

@Volhout thx!

@geoff That should be included in the manual as a pro tip.

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 3016

Posted: 08:42pm 09 Jan 2026

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An example of using it to set a row of pins.

Dim integer n, Start.Pin.GP = 0, No.of.Pins = 8

For n = Start.PinGP To Start.Pin.GP + No.of.Pins - 1
SetPin MM.Info(pinno "GP"+Str$(n)), DOUT 'set the Port output pins
Next

Edited 2026-01-10 13:31 by phil99

pwillard
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Joined: 07/06/2022
Location: United States
Posts: 337

Posted: 08:20pm 10 Jan 2026

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Thanks for the tips. Much appreciated.

Canada_Cold
Regular Member

Joined: 11/01/2020
Location: Canada
Posts: 52

Posted: 07:53pm 14 Jan 2026

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Hi,

I just wanted to say thanks to Volhout and to phil99 for your input and the code examples. That was very helpful.

I also agree with homa, it would be nice to have examples in the manual. And if not in the manual, maybe on the fruitoftheshed.com website and referenced in the manual.

Don

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