Code:
DEFINE OSC 48 ' We're using a 20MHz oscillator
ADCON1 = 7 ' Make pins digital
DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 24h ' Enable transmit, BRGH = 1
DEFINE HSER_CLROERR 1 ' Clear overflow automatically
DEFINE HSER_SPBRG 225 ' 9600 Baud @ 48MHz, 0.0%
SPBRGH = 4
BAUDCON.3 = 1 ' Enable 16 bit baudrate generator
HSEROUT [13,10,"Starting"]
Comm_Pin VAR PortA.0 ' One-wire Data-Pin "DQ" on PortC.0
Busy VAR BIT ' Busy Status-Bit
R_Temp VAR WORD ' RAW Temperature readings
TempC VAR WORD ' Temp in deg C
TempF VAR WORD ' Temp in deg F
Float VAR WORD ' Holds remainder for + temp C display
Cold_Bit VAR R_Temp.Bit11' Sign-Bit for +/- Temp. 1 = Below 0 deg C
Real_Cold CON 1 ' Define Real_Cold = 1
BAUD CON 16468 ' N9600 for serial LCD
DISP VAR PortB.0 ' Pin to drive serial LCD
Deg CON 223 ' Data to display Deg ° symbol
CLR CON 1 ' CLR LCD command
LINE1 CON 128 ' LCD line #1
LINE2 CON 192 ' LCD line #2
LINE3 CON 148 ' LCD line #3
LINE4 CON 212 ' LCD line #4
INS CON 254 ' LCD command mode parameter
Sign VAR BYTE ' +/- sign for temp display
Dummy VAR BYTE ' Dummy for Div32
Start_Convert:
OWOUT Comm_Pin, 1, [$CC, $44]' Skip ROM search & do temp conversion
Pause 2000
Wait_Up:
OWIN Comm_Pin, 4, [Busy] ' Read busy-bit
hserout [13,10,"Busy"]
pause 100
IF Busy = 0 THEN Wait_Up ' Still busy..?, Wait_Up..!
OWOUT Comm_Pin, 1, [$CC, $BE]' Skip ROM search & read scratchpad memory
OWIN Comm_Pin, 2, [R_Temp.Lowbyte, R_Temp.Highbyte]' Read two bytes / end comms
GOSUB Convert_Temp
GOTO Start_Convert
Convert_Temp: ' +32.0 to +257 F
IF Cold_Bit = Real_Cold THEN Yikes ' If Cold_Bit = 1, it's below "0" deg C
Sign = "+"
Dummy = 625 * R_Temp ' Multiply to load internal registers with 32-bit value
TempC = DIV32 10 ' Use Div32 value to calculate precise deg C
Dummy = 1125 * R_Temp
TempF = DIV32 100
IF TempF >6795 THEN ' Over 99.5 deg F..?
TempF = TempF + 3200
HSEROUT [13,10, " TempF = ",Sign,DEC TempF DIG 4,_
DEC TempF DIG 3,DEC TempF DIG 2,".",DEC2 TempF,Deg,"F "]
ELSE
TempF = TempF + 3200
HSEROUT [13,10, " TempF = ",Sign,DEC TempF DIG 3,_
DEC TempF DIG 2,".",DEC2 TempF,Deg,"F "]
ENDIF
TempC = (R_Temp & $0FF0) >> 4 ' Mask middle 8-bits, shift into lower byte
Float = ((R_Temp.Lowbyte & $0F) * 625) ' Lower 4-bits of result * 625
HSEROUT [13,10, " TempC = ",Sign,DEC TempC,".",DEC Float,Deg,"C "]
HSEROUT [13,10, "Raw", IBIN16 R_Temp]
RETURN
Yikes: ' Display full range -C to -F conversion
Sign = "-" ' Display - symbol for negative temp
Dummy = 625 * ~R_Temp+1' Multiply to load internal registers with 32-bit value
TempC = DIV32 10 ' Use Div32 value to calculate precise deg C
TempF = ~R_Temp / 16 ' Begin conversion from -C to deg +/-F
IF TempF >=18 THEN ' Check for -degrees F "-18 C = -0.4 F"
TempF = ((((TempF + 50) * 9) /5) -122) ' -C to -F below -17 deg C
HSEROUT [13,10, " TempF = ",Sign, DEC TempF,Deg,"F "]
HSEROUT [13,10, " TempC = ",Sign,DEC TempC DIG 4,_
DEC TempC DIG 3,".",DEC3 TempC,Deg,"C "]
HSEROUT [13,10, "Raw", IBIN16 R_Temp]
ELSE ' Else result = +deg F
TempF = ((((-TempF + 50) * 9) /5) -58)' -C to +F below 32.0 deg F to -17 deg C
HSEROUT [13,10, " TempF = ","+",DEC TempF,Deg,"F "]
HSEROUT [13,10, " TempC = ",Sign,DEC TempC DIG 4,_
DEC TempC DIG 3,".",DEC3 TempC,Deg,"C "]
HSEROUT [13,10, "Raw", IBIN16 R_Temp]
ENDIF
RETURN
END
The second really simple bit of code just outputs 00.0
Code:
define OSC 48
ADCON1 = 7 ' Set PORTA to digital
DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 24h ' Enable transmit, BRGH = 1
DEFINE HSER_CLROERR 1 ' Clear overflow automatically
DEFINE HSER_SPBRG 225 ' 9600 Baud @ 48MHz, 0.0%
SPBRGH = 4
BAUDCON.3 = 1 ' Enable 16 bit baudrate generator
HSEROUT [13,10,"Starting"]
DQ var PORTA.0
temp var word
loop:
owout DQ,1,[$cc]
owout DQ,0,[$44]
Pause 2000
owout DQ,1,[$cc]
owout DQ,0,[$be]
owin DQ,0,[temp.byte0,temp.byte1]
temp=temp*5
HSEROUT [13,10, " Temp = ",DEC2 temp/10,".", dec1 temp," ","C"]
goto loop
These bits of code come from sources that swear they work. What else could it be?!?!! For now I will try and send something else down USB to VB!!
DS1820 and 18f2550
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