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Duesentrieb
11.07.2008, 20:16
Hallo,

auf der Seite von MSC Electronics habe ich einen Code zur Auswertung von DS1820 1-Wire Temperaturfühler gefunden.

Das Problem dass ich damit habe ist, dass ich es nicht schaffe den Code so anzupassen dass die Fühler nur auf Befehl abgefragt werden.
Das eigentliche Hauptprogramm soll quasi den Befehl zur Abfrage geben.

Kann mir jemand helfen?
Ich benötige ja eigentlich nur zwei Temperaturen auf Anforderung.
Aber dass was ich hier gefunden habe ist sehr komplex


$regfile = "8515def.dat"
$crystal = 4000000

Declare Sub Init
Declare Sub ConvAllT ' Convert T on ALL sensors
Declare Function Decigrades(BYVAL sc(9) as byte) as integer

Config 1wire = Portb.6 '0,1,2 NOP 3,4,5,6,7 works good ON MY Equipment
Config Lcd = 16 * 2
Config Lcdpin = Pin , Db4 = Porta.4 , Db5 = Porta.5 , Db6 = Porta.6 , Db7 = Porta.7 , E = Porta.3 , Rs = Porta.2

'Temp variables
Dim B As Byte
Dim W As Word

'Program variables
'Implicit Err created by compiler
Dim Dg As Integer 'DECIgrades, I call it, cause I have no space for commas on the display....
Dim Min1 As Integer
Dim Min2 As Integer
Dim Max1 As Integer
Dim Max2 As Integer

Dim Dsid1(8) As Byte 'Dallas ID 64 bits incl CRC
Dim DsId2(8) As Byte
'When used like this : DsId(1) = 1wread(8)
'DsId(1) = family code 'Ds1820 10h, DS18B20 28h, Ds18s20 10h
'DsId(2) '48 Bits Serial, LSB
'DsId(3)
'DsId(4)
'DsId(5)
'DsId(6)
'DsId(7) '48 Bits Serial, MSB
'DsId(8) '8 CRC

Dim Sc(9) as byte 'Scratchpad 0-8 72 bits incl CRC, explanations for DS18b20
'Sc(1) 'Temperature LSB
'Sc(2) 'Temperature MSB
'Sc(3) 'TH/user byte 1 also SRAM
'Sc(4) 'TL/user byte 2 also SRAM
'Sc(5) 'config also SRAM x R1 R0 1 1 1 1 1 - the r1 r0 are config for resolution - write FF to byte for 12 bit - others dont care
'Sc(6) 'res
'Sc(7) 'res
'Sc(8) 'res
'Sc(9) '8 CRC

'DALLAS DS18B20 ROM and scratchpad commands''''''''''''''''''''''''''1wwrite....
'&H 33 read rom - single sensor
'&H 55 match rom, followed by 64 bits
'&H CC skip rom
'&H EC alarm search - ongoining alarm >TH <TL
'&H BE read scratchpad
'&H 44 convert T

cls

lcd "This is a 2sensor DS18B20 thermometer"
locate 2,1
lcd " by gote@sys-op.com"
wait 1
for b = 1 to 20
shiftlcd left
waitms 500
next
wait 2
cls
W = 1wirecount()

' Here I assume 2 sensors - no errorcontrol made, but would be easy to do with the "Err"-variable
' Getting the two sensors IDs.
DsId1(1) = 1wsearchfirst()
Do
DsId2(1) = 1wsearchnext()
Loop Until Err = 1

' If displayed, everything went well.
' First sensor identified and stored in variable
if dsid1(8) = crc8(DsId1(1), 7) then ' Control that the received CRC match the calculated
locate 1,1
lcd "CRC OK Sensor 1 ID"
wait 1
locate 1,1
for B=1 to 8
lcd Hex(DsId1(b))
next
end if

' Second sensor
if dsid2(8) = crc8(DsId2(1), 7) then
locate 2,1
lcd "CRC OK Sensor 2 ID"
wait 1
locate 2,1
for B=1 to 8
lcd Hex(DsId2(b))
next
end if
wait 1
cls

Init

' Main loop
Do
ConvAllT ' "Convert ALL T on the 1w-bus"
Waitus 200 : waitus 200 : waitus 200 : waitus 200 'if you use 2-wire, could be reduced to 200us

1wverify DsId1(1) 'Issues the "Match ROM "
locate 1,1
if err = 1 then
lcd "Err " 'Err = 1 if something is wrong
elseif err = 0 then 'lcd " Sensor found"
1wwrite &HBE
Sc(1) = 1wread(9) 'read bytes into array
if sc(9) = crc8(sc(1),8) then
DG = DeciGrades(sc(9))
if min1 > dg then min1 = dg
if max1 < dg then max1 = dg
lcd dg : locate 1,7 : lcd min1 : locate 1,14 : lcd max1
end if
end if

1wverify DsId2(1)
locate 2,1
if err = 1 then
lcd "DsId2 not on bus "
elseif err = 0 then ' lcd " Sensor found "
1wwrite &HBE
Sc(1) = 1wread(9)
if sc(9) = crc8(sc(1),8) then
DG = DeciGrades(sc(9))
if min2 > dg then min2 = dg
if max2 < dg then max2 = dg
lcd dg : locate 2,7 : lcd min2 : locate 2,14 : lcd max2
end if
end if
wait 1
loop
end 'end program

'Sets variables and LCD for further use'''''''''''''''''''''''''''''''''''''''''
Sub Init
Cls
Lcd " Min Max"
locate 2,1
Lcd " Min Max"
Min1 = 999 ' to get a real value from start
Min2 = 999
end sub

'Makes the Dallas "Convert T" command on the 1w-bus configured in "Config 1wire = Portb. "
'WAIT 200-750 ms after issued, internal conversion time for the sensor''''''''''
'SKIPS ROM - so it makes the conversion on ALL sensors on the bus simultaniously
'When leaving this sub, NO sensor is selected, but ALL sensors has the actual
'temperature in their scratchpad ( within 750 ms )
Sub ConvAllT
1wreset ' reset the bus
1wwrite &HCC ' skip rom
1wwrite &H44 ' Convert T
End sub

'Makes a integer value of the first two bytes in scratchpad'''''''''''''
'Works on DS18 B 20 , observe "B". The R0 and R1 in Sc(5) tells you how many bits are accurate
function Decigrades(Byval Sc(9) as byte)
Decigrades = 0
Decigrades = Makeint(Sc(1) , Sc(2))
Decigrades = Decigrades * 10
Decigrades = Decigrades / 16
end function

' If you have DS1820 or DS18 S 20 , you can use this algo instead:
' Observe that DsId1(1) contains the info value of which sensor is used.

'(
Function Decigrades(byval Sc(9) As Byte)
Dim Tmp As Byte , T As Integer , T1 As Integer

Tmp = Sc(1) And 1 ' 0.1C precision
If Tmp = 1 Then Decr Sc(1)
T = Makeint(sc(1) , Sc(2))
'Print Hex(t)
'Print T

T = T * 50 'here we calculate the 1/10 precision like
T = T - 25 'DS18S20 data sheet
T1 = Sc(8) - Sc(7)
T1 = T1 * 100
T1 = T1 / Sc(8)
T = T + T1
Decigrades = T / 10
'As integer, this routine gives T*10, with 1/10 degree precision
End Function
')

Duesentrieb
11.07.2008, 21:42
Hat sich erledigt!
Habe das Problem gefunden, Programm läuft!