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ville56
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Joined: 08/06/2022
Location: Austria
Posts: 411

Posted: 09:55am 23 Feb 2026

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is there a programatic way to map from pin name to PWM nuber like in

SETPIN GP15, PWMnc 'n=number c=channel

I found no other way so far as to loop thru all number and channel combinations for a given pin name and trapping an error, if any, or using the first non-error path as result, so plain try and error ...

But there is certainly a mor elegant solution I missed ....

73 de OE1HGA, Gerald

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10982

Posted: 10:02am 23 Feb 2026

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For SETPIN you can just use PWM. You don't need the "nc"
I'll add a new mm.info(pwm pin) that will return the channel for a given pin. Will be in V6.02.01b6

ville56
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Posted: 10:05am 23 Feb 2026

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Thanks Peter, wasn't aware of the SETPIN without nc .... the new mm.info will also be helpful in such cases, thank you.

73 de OE1HGA, Gerald

ville56
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Posted: 12:07pm 23 Feb 2026

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Peter,

MM.INFO(PWM COUNT) as of the manual does not work ...

> print MM.INFO(PWM COUNT)
Error : Invalid syntax
>

PicoMite MMBasic RP2350B V6.02.01b5
OPTION FLASH SIZE 16777216
OPTION COLOURCODE ON
OPTION PICO OFF
OPTION CPUSPEED (KHz) 200000

73 de OE1HGA, Gerald

matherp
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Posts: 10982

Posted: 12:16pm 23 Feb 2026

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You need to specify the slice
mm.info(pwm count n)
where n=0-7 for the RP2040 and 0-11 for the RP2350
For mm.info(PWM DUTY n,m) you also need to specify the channel 0 or 1

ville56
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Posted: 12:24pm 23 Feb 2026

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Peter,

the manual says for mm.info(pwm count)

"Returns the number of PWM channels supported by the chip"

so I see no use for specifying a "slice", whatever this should be. I tried with several different slice numbers, they all give 65535 as result. Doesn't make sense for me. I would have expected something between 0 and 11, depending on the chip.

73 de OE1HGA, Gerald

matherp
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Location: United Kingdom
Posts: 10982

Posted: 12:27pm 23 Feb 2026

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The manual is wrong - will get it updated. It returns the total count of the pwm slice given the frequency

Quote > setpin gp0,pwm
> pwm 0,1000,50
> ? mm.info(pwm count 0)
62999
> pwm 0,1000000,50
> ? mm.info(pwm count 0)
251
>

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