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lizby
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Posted: 03:03pm 20 May 2026

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With the latest version, ?tempr isn't working for me on an RP2350-Zero. I reflashed V6.00.01 and it worked; flashed again immediately with V6.03.00RC9 and it returns 1000. It does this on all the pins I have tried.

PicoMite MMBasic RP2350A Edition V6.00.01
Copyright 2011-2024 Geoff Graham
Copyright 2016-2024 Peter Mather

> ?tempr(gp29)
25
PicoMite MMBasic RP2350A V6.03.00RC9
Copyright 2011-2026 Geoff Graham
Copyright 2016-2026 Peter Mather

Formatting the A: drive
> ?tempr(gp29)
1000
>

~
Edited 2026-05-21 01:04 by lizby

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matherp
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Posted: 03:25pm 20 May 2026

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Haven't got a ds18b20 with me so can't really look at it for the next couple of weeks. Can you find in which version it first stopped working then I might have a chance.

lizby
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Posted: 03:59pm 20 May 2026

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It fails at RP2350A V6.01.00

PicoMite MMBasic RP2350A V6.01.00
Copyright 2011-2025 Geoff Graham
Copyright 2016-2025 Peter Mather

Formatting the A: drive
> ?tempr(gp29)
1000

I don't have anything between RP2350A V6.00.01 and V6.01.00, and Geoff's archive doesn't contain and V6 versions. (Unfortunately, V6.00.01 doesn't contain trim$--I'll cobble a version.)

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matherp
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Posted: 04:31pm 20 May 2026

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What about 6.02.01 on Geoff's site?

mozzie
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Posted: 05:00pm 20 May 2026

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G'day Lizby,
Have you tried other pins? Works here on GP0 / GP28 on RP2350A V6.03.00RC9

> option list
PicoMite MMBasic RP2350A V6.03.00RC9
OPTION SYSTEM SPI GP18,GP19,GP16
OPTION FLASH SIZE 4194304
OPTION COLOURCODE ON
OPTION CPUSPEED (KHz) 200000
OPTION LCDPANEL ST7796S, LANDSCAPE,GP14,GP13,GP12
OPTION GUI CONTROLS 64
OPTION TOUCH GP15,GP17
GUI CALIBRATE 0, 3978, 3840, -1298, -868
> ? tempr(gp0)
26.25
> ? tempr(gp28)
26
>

This is on a RPI Pico2 so no access to GP29

Regards, Lyle.

Edit: Just re-read your original post and it appears you have tried other pins

Edited 2026-05-21 03:03 by mozzie

Mixtel90

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Posted: 05:25pm 20 May 2026

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Unless MMBasic does something clever GP29 isn't an ADC input on a RP2350A or B.

Mick

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

lizby
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Posted: 05:45pm 20 May 2026

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PicoMite MMBasic RP2350A V6.03.00RC9
Copyright 2011-2026 Geoff Graham
Copyright 2016-2026 Peter Mather

> ?tempr(GP5)
1000
> ?tempr(GP0)
1000
> option list
PicoMite MMBasic RP2350A V6.03.00RC9
OPTION FLASH SIZE 4194304
OPTION COLOURCODE ON
OPTION CPUSPEED (KHz) 340000
> ?tempr(GP0)
1000
> ?tempr(GP1)
1000
> update firmware
PicoMite MMBasic RP2350A Edition V6.00.01
Copyright 2011-2024 Geoff Graham
Copyright 2016-2024 Peter Mather

> ?tempr(gp1)
25
> update firmware
PicoMite MMBasic RP2350A V6.02.01
Copyright 2011-2026 Geoff Graham
Copyright 2016-2026 Peter Mather

Formatting the A: drive
> ?tempr(gp1)
1000
>

No go for me with RP2350A V6.02.01. I don't understand why RP2350A V6.03.00RC9 worked for Lyle but not for me.

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mozzie
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Posted: 05:46pm 20 May 2026

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G'day Lizby,
Managed to find the RP2350-Zero purchased by mistake, GP29 does work with the DS18B20:

> option list
PicoMite MMBasic RP2350A V6.03.00RC4
OPTION FLASH SIZE 4194304
OPTION COLOURCODE ON
OPTION CPUSPEED (KHz) 200000
OPTION DISPLAY 40, 80
> ? tempr(gp29)
25.25
>

This is using the "Normal Power" option as shown in the manual, I had a heap of trouble with the "Parasitic Power" system as it seems to be quite dependent on device quality. Maybe this is causing what you are seeing.

Might also be worth trying TEMPR START with a long timeout, I think this helped with slow sensors. Strange it worked on the older version though

Mick, the DS18B20 uses the one wire protocol so will work on any pin, the TMP37 etc is perhaps what you have in mind?

Regards, Lyle.
Edited 2026-05-21 03:54 by mozzie

Mixtel90

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Posted: 06:16pm 20 May 2026

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Sorry, brain's gone...
I'm concentrating on aquarium stands at the moment, not electronics. It shows, doesn't it? :)

Mick

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

JanVolk
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Posted: 06:40pm 20 May 2026

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G'day Lizby,

Rejected DS18B20 temperature sensors are left out in later versions and can be used with an extra timeout.
Or try the code below.

' Function TEMPR() and TEMPW() Dallas DS18B20. V6.03.00RC10
Const Pin$="GP14"

Do
Print
Print "DS18B20 TEMPW(";Pin$;"):"; Str$(TEMPW(Pin$),3,2);" "; Chr$(176);"C"
Print "DS18B20 TEMPR(GP14):"; Str$(TEMPR(GP14),3,2);" "; Chr$(176);"C"
Print "DS18B20 TEMPR(GP14):"; Str$(TEMPR(GP14,200),3,2);" "; Chr$(176);"C"
' TEMPR(pin [,timeout]) Manual: Ver 6.02.01 Page 200 PicoMite User Manual.
Pause 5000
Loop

Function TEMPW(Pin$)
Local T1,T2,b,t
OneWire Reset Pin$
OneWire Write Pin$,1,2,&HCC,&H44
Pause 80
t=Timer
OneWire Write Pin$,1,2,&HCC,&HBE
OneWire Read Pin$,2,2,T1,T2
TEMPW = ((T2 And &B111)*256+T1)/16
If T2 And &B1000 Then TEMPW=-TEMPW
End Function

Jan.

phil99

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Posted: 09:46pm 20 May 2026

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mozzie said Might also be worth trying TEMPR START with a long timeout

Yes, I have one that is fussy about that.
TEMPR START is essential for that one, and it reads a bit high so I think it's a fake.

Sub DS18B20
TEMPR START 9,3
TEMPR START 10,3
DS1 = Cint(TEMPR(9)*10)/10
DS2 = Cint(TEMPR(10)*10)/10
End Sub

Edited 2026-05-21 07:53 by phil99

lizby
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Posted: 11:35pm 20 May 2026

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The timeout fixes it:

PicoMite MMBasic RP2350A V6.02.01
Copyright 2011-2026 Geoff Graham
Copyright 2016-2026 Peter Mather

> ?tempr(gp1,500)
24.25
> ?tempr(gp1)
1000
>
> update firmware
PicoMite MMBasic RP2350A V6.03.00RC9
Copyright 2011-2026 Geoff Graham
Copyright 2016-2026 Peter Mather

Formatting the A: drive
> ?tempr(gp1)
1000
> ?tempr(gp1,300)
1000
> ?tempr(gp1,400)
1000
> ?tempr(gp1,500)
24.75
>

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

JanVolk
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Posted: 11:50pm 20 May 2026

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PicoMite MMBasic RP2350A V6.03.00RC10
Copyright 2011-2026 Geoff Graham
Copyright 2016-2026 Peter Mather

> new
> tempr(gp14,170)
19.75

Jan.

Peter63
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Joined: 28/07/2017
Location: Sweden
Posts: 171

Posted: 07:18am 21 May 2026

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Have tried connecting DS18S20 (yes S20)
Getting strange values, have tested 4 out of 10 that I have...

> new
> tempr(gp7)
10.625
> tempr(gp7)
10.625
> tempr(gp7)
10.625
> tempr(gp7,170)
10.625
> tempr(gp7,170)
10.625
> tempr(gp7,800)
3.1875
> tempr(gp7,800)
3.1875
> tempr(gp7,800)
3.1875

I have a temperature of 25 degrees in the room.

using PicoMite MMBasic USB RP2350B Edition V6.03.00RC10

tested and the device DS18S20, works on an Arduino UNO (5V)

/Peter63
Edited 2026-05-21 17:50 by Peter63

matherp
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Posted: 08:37am 21 May 2026

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The ds18s20 isn't supported by MMBasic. It functions differently and is not compatible

phil99

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Posted: 08:45am 21 May 2026

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Does this make any difference?

> TEMPR START gp7,3 : TEMPR(gp7)

dddns
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Posted: 08:45am 21 May 2026

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some more info ..at the time when timeout parameter was introduced

Peter63
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Posted: 09:00am 21 May 2026

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Quote some more info ..at the time when timeout parameter was introduced

i tested the program

Quote TassyJim's test program with some mods for the PicoMite.

, and this display OK temp value...

Family name: DS1820/DS18S20
Rom Code: 10 B4 65 B5 02 08 00 CA
ScratchPad: 32 00 00 00 FF FF 0A 10
Power mode Parasitic

ScratchPad: 32 00 FF FF FF FF 0A 10
Temperature: 25.0625 775.005mS, 9 bit

ScratchPad: 32 00 FF FF FF FF 0B 10
Temperature: 25.125 774.997mS, 10 bit

ScratchPad: 32 00 FF FF FF FF 0A 10
Temperature: 25.1875 774.974mS, 11 bit

ScratchPad: 32 00 FF FF FF FF 09 10
Temperature: 25.1875 774.985mS, 12 bit

Tempr() without start 10.625
Tempr Start Pin,0 10.625
Tempr Start Pin,1 10.625
Tempr Start Pin,2 10.625
Tempr Start Pin,3 3.125

huummm... /Peter63

Peter63
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Posted: 09:05am 21 May 2026

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Quote Does this make any difference?
> TEMPR START gp7,3 : TEMPR(gp7)

result...

Quote > tempr start gp7,3:tempr(gp7)
3.125
> tempr start gp7,3:tempr(gp7)
3.1875
> tempr start gp7,3:tempr(gp7)
3.1875

/Peter63

matherp
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Posted: 09:07am 21 May 2026

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The ds18s20 isn't supported by MMBasic. It functions differently and is not compatible

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