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Joined: 11/02/2018
Location: AustraliaPosts: 3013
| Posted: 05:51am 10 Mar 2025 |
More playing with Jim's program. Added some comments to help add unknown / non-genuine devices.
'DS18x20 test code by TassyJim
Print
' Input "Type Pin number ",PinNbr
Input "Type PicoMite GPxx number for the DS18B20 (include the GP) "; GPPin$
Dim INTEGER PinNbr = MM.Info(pinno GPPin$)
Print
Print "Family name: ";FamilyName$(PinNbr)
Print "Rom Code: ";getRomCode$(PinNbr)
Print "ScratchPad: ";getScratchpad$(PinNbr)
If powerMode(PinNbr) Then
Print "Power mode External"
Else
Print "Power mode Parasitic"
EndIf
Print
For n = 9 To 12
Print
x = setResolution(PinNbr, n)
Print "ScratchPad: ";getScratchpad$(PinNbr)
Timer = 0
Print "Temperature: ";getTemp(PinNbr);"`C ";Timer;"mS,";n;" bit"
Next n
Print :t=Timer : Print "Tempr() without Start", TEMPR(PinNbr);" `C",Timer-t;" mS"
TEMPR START PinNbr,0 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,0", ds18, t
TEMPR START PinNbr,1 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,1", ds18, t
TEMPR START PinNbr,2 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,2", ds18, t
TEMPR START PinNbr,3 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,3", ds18, t
Print
Print "*** The first RomCode value (a1) can be used to add extra devices to the FamilyName & getTemp functions"
Print "look for *** comments in those functions"
Print
End
Function getRomCode$(PinNbr As INTEGER)
' get ROM Code - useful if you want more than 1 device on wire
'*** The first value returned (a1) can be used to add extra devices to the FamilyName & getTemp functions
'look for *** comments in those functions
Local INTEGER a1,a2,a3,a4,a5,a6,a7,a8
OneWire WRITE PinNbr,1,1,&h33 'read ROM code
OneWire READ PinNbr,0,8,a1,a2,a3,a4,a5,a6,a7,a8
getRomCode$ = Hex$(a1,2)+" "+Hex$(a2,2)+" "+Hex$(a3,2)+" "+Hex$(a4,2)+" "+Hex$(a5,2)+" "+Hex$(a6,2)+" "+Hex$(a7,2)+" "+Hex$(a8
,2)
End Function
Function getScratchpad$(PinNbr As INTEGER)
'ONEWIRE Write PinNbr,1,9,&h55,a1,a2,a3,a4,a5,a6,a7,a8 'read from scratchpad
OneWire WRITE PinNbr,1,2,&hcc,&hbe
OneWire READ PinNbr,0,8,a,b,c,d,e,f,g,h
getScratchpad$ = Hex$(a,2)+" "+Hex$(b,2)+" "+Hex$(c,2)+" "+Hex$(d,2)+" "+Hex$(e,2)+" "+Hex$(f,2)+" "+Hex$(g,2)+" "+Hex$(h,2)
End Function
Function powerMode(PinNbr As INTEGER) As INTEGER
' check whether power external (1) or parasitic (0)
OneWire RESET PinNbr
OneWire WRITE PinNbr, 1,2,&hcc, &hb4
OneWire READ PinNbr,4,1,powerMode
End Function
Function getFamily(PinNbr As INTEGER) As INTEGER
getFamily = Val("&h"+Left$(getRomCode$(PinNbr),2))
End Function
Function FamilyName$(PinNbr As INTEGER)
Local INTEGER fn
fn = getFamily(PinNbr)
Select Case fn
Case 16 '&H10
FamilyName$ = "DS1820/DS18S20"
Case 34 '&H22
FamilyName$ = "DS18S22"
Case 40 '&H28
FamilyName$ = "DS18B20"
Case 41 '&H29
FamilyName$ = "a non-genuine DS18B20"
'*** Add extra cases here using the first value returned by Function getRomCode
Case Else
FamilyName$ = "Unknown"
End Select
End Function
Function setResolution(PinNbr As INTEGER,r As INTEGER)
r = r-9
If r < 0 Then r = 0
If r > 3 Then r = 3
r = r*32+31
OneWire WRITE PinNbr, 1,5,&hcc, &h4E, &hFF,&hFF,r
End Function
Function getTemp(PinNbr As INTEGER) As FLOAT
Local INTEGER fn, t, T1, T2, a,b,c,d,e,f,g,h
Local FLOAT Value
fn = getFamily(PinNbr)
power = powerMode(PinNbr)
OneWire RESET PinNbr ' reset before command
OneWire WRITE PinNbr, 8, 2, &hcc, &h44 ' start conversion
'read external when b goes high, for parasitic just wait
If power = 0 Then
Pause 750
Else
t = Timer
Do
If Timer - t > 1000 Then
Value = 1000
Print "*** Timeout ***"
Exit Do
EndIf
OneWire READ PinNbr, 4 , 1 , b ' conversion done?
Loop Until b = 1
' Print Timer-t;" mS conversion time",
EndIf
If Value = 0 Then ' we have not timed out yet
OneWire WRITE PinNbr, 1, 2, &hcc, &hbe ' command read data
OneWire READ PinNbr, 2, 2, T1, T2 ' get the data
OneWire RESET PinNbr
Select Case fn
Case 16 'DS18S20 or DS1820
OneWire WRITE PinNbr,1,2,&hcc,&hbe
OneWire READ PinNbr,0,8,a,b,c,d,e,f,g,h
If T2 And &h80 Then 'if MSB of T2=1 then negative
'Read 12bit resolution and adjust
'truncate 0.5deg value (or use integer division \)
T1 = T1 And &hFE
T1=T1 / 2 'make whole degrees
'add compensation values read from scratchpad
T1=T1*16 'make lsb 1/16 degree
T1 = T1 -4 +(16 - g) 'add 12 bit value
'take 2s complement
T1 = (T1 Xor &hFF) + 1
Value = -T1/16 'make decimal value in degrees
Else 'positive temp
Value = T1 / 2 '9bit value
'Read 12bit resolution and adjust
T1 = T1 And &hFE 'truncate 0.5deg(or use integer division \)
Value = T1/2- 0.25 + (16 - g) /16 '12 bit value
EndIf
Case 34, 40 ' DS18S22 or DS18B20
If T2 And &b1000 Then 'negative temp
'make 2s complement (1s complement+1)
T2 = (T2 Xor &hFF)
T1 = (T1 Xor &hFF)+1
If T1=1 Then T2=T2+1 'add the carry if required
Value = -((T2 And &b111) * 256 + T1) / 16
Else 'positive temp
Value = ((T2 And &b111) * 256 + T1) / 16
EndIf
Case 41 '&H29, a non genuine DS18B20
If T2 And &b1000 Then 'negative temp
'make 2s complement (1s complement+1)
T2 = (T2 Xor &hFF)
T1 = (T1 Xor &hFF)+1
If T1=1 Then T2=T2+1 'add the carry if required
Value = -((T2 And &b111) * 256 + T1) / 16
Else 'positive temp
Value = ((T2 And &b111) * 256 + T1) / 16
EndIf
'*** Add extra cases here using the first value returned by Function getRomCode
Case Else 'Unknown device
' *** use the output of this to create the scale factor of the unknown device
'Value = 1000
If T2 And &b1000 Then 'negative temp
'make 2s complement (1s complement+1)
T2 = (T2 Xor &hFF)
T1 = (T1 Xor &hFF)+1
If T1=1 Then T2=T2+1 'add the carry if required
Value = -((T2 And &b111) * 256 + T1) / 1'<-This is where you put the scale factor
Else 'positive temp
Value = ((T2 And &b111) * 256 + T1) / 1'<-This is where you put the scale factor
EndIf
End Select
EndIf
getTemp= Value
End Function
' Input "Type Pin number ",PinNbr
Input "Type PicoMite GPxx number for the DS18B20 (include the GP) "; GPPin$
Dim INTEGER PinNbr = MM.Info(pinno GPPin$)
Print "Family name: ";FamilyName$(PinNbr)
Print "Rom Code: ";getRomCode$(PinNbr)
Print "ScratchPad: ";getScratchpad$(PinNbr)
If powerMode(PinNbr) Then
Print "Power mode External"
Else
Print "Power mode Parasitic"
EndIf
For n = 9 To 12
x = setResolution(PinNbr, n)
Print "ScratchPad: ";getScratchpad$(PinNbr)
Timer = 0
Print "Temperature: ";getTemp(PinNbr);"`C ";Timer;"mS,";n;" bit"
Next n
Print :t=Timer : Print "Tempr() without Start", TEMPR(PinNbr);" `C",Timer-t;" mS"
TEMPR START PinNbr,0 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,0", ds18, t
TEMPR START PinNbr,1 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,1", ds18, t
TEMPR START PinNbr,2 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,2", ds18, t
TEMPR START PinNbr,3 :t=Timer :ds18=TEMPR(PinNbr):t=Timer-t : Print "Tempr Start pin,3", ds18, t
Print "*** The first RomCode value (a1) can be used to add extra devices to the FamilyName & getTemp functions"
Print "look for *** comments in those functions"
End
Function getRomCode$(PinNbr As INTEGER)
' get ROM Code - useful if you want more than 1 device on wire
'*** The first value returned (a1) can be used to add extra devices to the FamilyName & getTemp functions
'look for *** comments in those functions
Local INTEGER a1,a2,a3,a4,a5,a6,a7,a8
OneWire WRITE PinNbr,1,1,&h33 'read ROM code
OneWire READ PinNbr,0,8,a1,a2,a3,a4,a5,a6,a7,a8
getRomCode$ = Hex$(a1,2)+" "+Hex$(a2,2)+" "+Hex$(a3,2)+" "+Hex$(a4,2)+" "+Hex$(a5,2)+" "+Hex$(a6,2)+" "+Hex$(a7,2)+" "+Hex$(a8
,2)
End Function
Function getScratchpad$(PinNbr As INTEGER)
'ONEWIRE Write PinNbr,1,9,&h55,a1,a2,a3,a4,a5,a6,a7,a8 'read from scratchpad
OneWire WRITE PinNbr,1,2,&hcc,&hbe
OneWire READ PinNbr,0,8,a,b,c,d,e,f,g,h
getScratchpad$ = Hex$(a,2)+" "+Hex$(b,2)+" "+Hex$(c,2)+" "+Hex$(d,2)+" "+Hex$(e,2)+" "+Hex$(f,2)+" "+Hex$(g,2)+" "+Hex$(h,2)
End Function
Function powerMode(PinNbr As INTEGER) As INTEGER
' check whether power external (1) or parasitic (0)
OneWire RESET PinNbr
OneWire WRITE PinNbr, 1,2,&hcc, &hb4
OneWire READ PinNbr,4,1,powerMode
End Function
Function getFamily(PinNbr As INTEGER) As INTEGER
getFamily = Val("&h"+Left$(getRomCode$(PinNbr),2))
End Function
Function FamilyName$(PinNbr As INTEGER)
Local INTEGER fn
fn = getFamily(PinNbr)
Select Case fn
Case 16 '&H10
FamilyName$ = "DS1820/DS18S20"
Case 34 '&H22
FamilyName$ = "DS18S22"
Case 40 '&H28
FamilyName$ = "DS18B20"
Case 41 '&H29
FamilyName$ = "a non-genuine DS18B20"
'*** Add extra cases here using the first value returned by Function getRomCode
Case Else
FamilyName$ = "Unknown"
End Select
End Function
Function setResolution(PinNbr As INTEGER,r As INTEGER)
r = r-9
If r < 0 Then r = 0
If r > 3 Then r = 3
r = r*32+31
OneWire WRITE PinNbr, 1,5,&hcc, &h4E, &hFF,&hFF,r
End Function
Function getTemp(PinNbr As INTEGER) As FLOAT
Local INTEGER fn, t, T1, T2, a,b,c,d,e,f,g,h
Local FLOAT Value
fn = getFamily(PinNbr)
power = powerMode(PinNbr)
OneWire RESET PinNbr ' reset before command
OneWire WRITE PinNbr, 8, 2, &hcc, &h44 ' start conversion
'read external when b goes high, for parasitic just wait
If power = 0 Then
Pause 750
Else
t = Timer
Do
If Timer - t > 1000 Then
Value = 1000
Print "*** Timeout ***"
Exit Do
EndIf
OneWire READ PinNbr, 4 , 1 , b ' conversion done?
Loop Until b = 1
' Print Timer-t;" mS conversion time",
EndIf
If Value = 0 Then ' we have not timed out yet
OneWire WRITE PinNbr, 1, 2, &hcc, &hbe ' command read data
OneWire READ PinNbr, 2, 2, T1, T2 ' get the data
OneWire RESET PinNbr
Select Case fn
Case 16 'DS18S20 or DS1820
OneWire WRITE PinNbr,1,2,&hcc,&hbe
OneWire READ PinNbr,0,8,a,b,c,d,e,f,g,h
If T2 And &h80 Then 'if MSB of T2=1 then negative
'Read 12bit resolution and adjust
'truncate 0.5deg value (or use integer division \)
T1 = T1 And &hFE
T1=T1 / 2 'make whole degrees
'add compensation values read from scratchpad
T1=T1*16 'make lsb 1/16 degree
T1 = T1 -4 +(16 - g) 'add 12 bit value
'take 2s complement
T1 = (T1 Xor &hFF) + 1
Value = -T1/16 'make decimal value in degrees
Else 'positive temp
Value = T1 / 2 '9bit value
'Read 12bit resolution and adjust
T1 = T1 And &hFE 'truncate 0.5deg(or use integer division \)
Value = T1/2- 0.25 + (16 - g) /16 '12 bit value
EndIf
Case 34, 40 ' DS18S22 or DS18B20
If T2 And &b1000 Then 'negative temp
'make 2s complement (1s complement+1)
T2 = (T2 Xor &hFF)
T1 = (T1 Xor &hFF)+1
If T1=1 Then T2=T2+1 'add the carry if required
Value = -((T2 And &b111) * 256 + T1) / 16
Else 'positive temp
Value = ((T2 And &b111) * 256 + T1) / 16
EndIf
Case 41 '&H29, a non genuine DS18B20
If T2 And &b1000 Then 'negative temp
'make 2s complement (1s complement+1)
T2 = (T2 Xor &hFF)
T1 = (T1 Xor &hFF)+1
If T1=1 Then T2=T2+1 'add the carry if required
Value = -((T2 And &b111) * 256 + T1) / 16
Else 'positive temp
Value = ((T2 And &b111) * 256 + T1) / 16
EndIf
'*** Add extra cases here using the first value returned by Function getRomCode
Case Else 'Unknown device
' *** use the output of this to create the scale factor of the unknown device
'Value = 1000
If T2 And &b1000 Then 'negative temp
'make 2s complement (1s complement+1)
T2 = (T2 Xor &hFF)
T1 = (T1 Xor &hFF)+1
If T1=1 Then T2=T2+1 'add the carry if required
Value = -((T2 And &b111) * 256 + T1) / 1'<-This is where you put the scale factor
Else 'positive temp
Value = ((T2 And &b111) * 256 + T1) / 1'<-This is where you put the scale factor
EndIf
End Select
EndIf
getTemp= Value
End Function
Example output. This one always reads 85° until after a Tempr Start pin,2 or 3 command then is ok till next power cycle.
> RUN
Type PicoMite GPxx number for the DS18B20 (include the GP) ? gp6
Family name: a non-genuine DS18B20
Rom Code: 29 61 64 12 3D D4 A4 B8
ScratchPad: 51 05 FF FF 7F FF FF FF
Power mode External
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 85.0625`C 17.934mS, 9 bit
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 85.0625`C 17.951mS, 10 bit
ScratchPad: A8 82 FF FF AF FF FF FF
Temperature: 680`C 17.91mS, 11 bit
ScratchPad: 51 05 FF FF 7F FF FF FF
Temperature: 85.0625`C 17.935mS, 12 bit
Tempr() without Start 85 `C 210.435 mS
Tempr Start pin,0 85 103.408
Tempr Start pin,1 85 203.84
Tempr Start pin,2 27.875 403.835
Tempr Start pin,3 27.875 803.819
*** The first RomCode value (a1) can be used to add extra devices to the FamilyName & getTemp functions
look for *** comments in those functions
> RUN
Type PicoMite GPxx number for the DS18B20 (include the GP) ? gp6
Family name: a non-genuine DS18B20
Rom Code: 29 61 64 12 3D D4 A4 B8
ScratchPad: BF 01 FF FF 7B FF FF FF
Power mode External
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 27.9375`C 17.964mS, 9 bit
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 27.9375`C 17.942mS, 10 bit
ScratchPad: DF 80 FF FF AF FF FF FF
Temperature: 223`C 17.93mS, 11 bit
ScratchPad: BF 01 FF FF 7F FF FF FF
Temperature: 27.9375`C 17.942mS, 12 bit
Tempr() without Start 27.875 `C 210.452 mS
Tempr Start pin,0 27.875 104.167
Tempr Start pin,1 27.875 203.82
Tempr Start pin,2 27.6875 403.821
Tempr Start pin,3 27.6875 803.819
*** The first RomCode value (a1) can be used to add extra devices to the FamilyName & getTemp functions
look for *** comments in those functions
Type PicoMite GPxx number for the DS18B20 (include the GP) ? gp6
Family name: a non-genuine DS18B20
Rom Code: 29 61 64 12 3D D4 A4 B8
ScratchPad: 51 05 FF FF 7F FF FF FF
Power mode External
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 85.0625`C 17.934mS, 9 bit
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 85.0625`C 17.951mS, 10 bit
ScratchPad: A8 82 FF FF AF FF FF FF
Temperature: 680`C 17.91mS, 11 bit
ScratchPad: 51 05 FF FF 7F FF FF FF
Temperature: 85.0625`C 17.935mS, 12 bit
Tempr() without Start 85 `C 210.435 mS
Tempr Start pin,0 85 103.408
Tempr Start pin,1 85 203.84
Tempr Start pin,2 27.875 403.835
Tempr Start pin,3 27.875 803.819
*** The first RomCode value (a1) can be used to add extra devices to the FamilyName & getTemp functions
look for *** comments in those functions
> RUN
Type PicoMite GPxx number for the DS18B20 (include the GP) ? gp6
Family name: a non-genuine DS18B20
Rom Code: 29 61 64 12 3D D4 A4 B8
ScratchPad: BF 01 FF FF 7B FF FF FF
Power mode External
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 27.9375`C 17.964mS, 9 bit
ScratchPad: FF FF FF FF FF FF FF FF
Temperature: 27.9375`C 17.942mS, 10 bit
ScratchPad: DF 80 FF FF AF FF FF FF
Temperature: 223`C 17.93mS, 11 bit
ScratchPad: BF 01 FF FF 7F FF FF FF
Temperature: 27.9375`C 17.942mS, 12 bit
Tempr() without Start 27.875 `C 210.452 mS
Tempr Start pin,0 27.875 104.167
Tempr Start pin,1 27.875 203.82
Tempr Start pin,2 27.6875 403.821
Tempr Start pin,3 27.6875 803.819
*** The first RomCode value (a1) can be used to add extra devices to the FamilyName & getTemp functions
look for *** comments in those functions
Edit.
Prompted by Volhout's mention of the RP2350 pin issue I reduced the pullup resistor from 10k to 1.2k. Now the Rom Code value of a1 is &H28, as it should be. Was &H29.
It no longer reads 85°C in Jim's program but still requires an initial Tempr Start to get Tempr() to read correctly.
Edited 2025-03-10 20:08 by phil99