Hallo,
habe jetzt mal den Sensor auf andere Ports gelegt (PD4 und PD5) allerdings mit dem gleichen Ergebnis! :-k
Auch ein anderes Beispiel Programm:
Code:
'Routine to read the SHT75 Humidity sensor chip
'By Stuart Leslie
'Contact stu@4sightinc.com with any questions
'Uses BascomAVR
'a .01 uf capacitor across VCC and Ground on the SHT75 really cleans up the data
'a pullup is required on "data" pin as shown in the data sheet
$regfile = "m8def.dat"
$crystal = 16000000 ' used crystal frequency
$baud = 9600 ' use baud rate
$hwstack = 32 ' default use 32 for the hardware stack
$swstack = 32 ' default use 10 for the SW stack
$framesize = 32 ' default use 40 for the frame space
Dim Ctr As Byte
Dim Dataword As Word
Dim Command As Byte
Dim Dis As String * 20
Dim Calc As Single
Dim Calc2 As Single
Dim Rhlinear As Single
Dim Rhlintemp As Single
Dim Tempc As Single
'Dim Tempf As Single
Const C1 = -4
Const C2 = 0.0405
Const C3 = -0.0000028
Const T1c = .01
Const T2 = .00008
'Const T1f = .018
Sck Alias Portd.4
Dataout Alias Portd.5
Datain Alias Pind.5
'Redled Alias PortD.2
Declare Sub Getit()
Ddrd = &B11111111 'all port b are output
Config Pind.4 = Output 'sck
Config Pind.5 = Output 'datain
'reset the serial communications first, it is easily confused!
Set Dataout
For Ctr = 1 To 12
Set Sck
Waitus 2
Reset Sck
Waitus 2
Next Ctr
Do 'continually read the tempfature and humidity
Command = &B00000011
Call Getit 'Get the temperature, puts result in "dataword" for us
'
'Tempf = T1f * Dataword
'Tempf = Tempf - 40
Tempc = T1c * Dataword 'get celcius for later calculations and for "the rest of the world"
Tempc = Tempc - 40
Dis = Fusing(tempc , "###.##")
Print "Temperatur = " ; Dis ; Chr(167) ; "C"
Command = &B00000101
Call Getit 'get the humidity
Calc = C2 * Dataword
Calc2 = Dataword * Dataword 'that "2" in the datasheet sure looked like a footnote for a couple days, nope it means "squared"!
Calc2 = C3 * Calc2
Calc = Calc + C1
Rhlinear = Calc + Calc2
'Dis = Fusing(rhlinear , "##.##")
'Print "Humidity adjusted for linear = " ; Dis
Calc = T2 * Dataword
Calc = Calc + T1c
Calc2 = Tempc - 25
Calc = Calc2 * Calc
Rhlintemp = Calc + Rhlinear
Dis = Fusing(rhlintemp , "##.##")
Print "Luftfeuchte = " ; Dis ; " %"
Wait 1
Loop
Sub Getit()
Local Datavalue As Word
Local Databyte As Byte
'start with "transmission start"
Set Sck
Reset Dataout
Reset Sck
Set Sck
Set Dataout
Reset Sck
'now send the command
Shiftout Dataout , Sck , Command , 1
Ddrd = &B11111101 'datain is now input
Config Pind.5 = Input 'datain
Set Sck 'click one more off
Reset Sck
Waitus 10 'no idea why, but it doesn't work without it!
Bitwait Pind.7 , Reset 'wait for the chip to have data ready
Shiftin Datain , Sck , Databyte , 1 'get the MSB
Datavalue = Databyte
Ddrd = &B11111111
Config Pind.5 = Output
Reset Dataout 'this is the tricky part- Lot's of hair pulling- have to tick the ack!
Set Sck
Reset Sck
Ddrd = &B11111101 'datain is now input
Config Pind.5 = Input
Shiftin Datain , Sck , Databyte , 1 'get the LSB
Shift Datavalue , Left , 8
Datavalue = Datavalue Or Databyte
'don't tick the clock or ack since we don't need the CRC value, leave it hanging!
Dataword = Datavalue
Ddrd = &B11111111
Config Pind.5 = Output
Reset Dataout
Set Sck
Reset Sck
Ddrd = &B11111101 'datain is now input
Config Pind.5 = Input
Shiftin Datain , Sck , Databyte , 1 'not using the CRC value for now- can't figure it out! Anybody know how to impliment?
'Print "CRC value was - " ; Databyte
Ddrd = &B11111111
Config Pind.5 = Output
Set Dataout
Set Sck
Reset Sck
End Sub
End
Funktionierte nicht!
Ausgabe war immer:
Code:
Temperatur = 612.80°C
Luftfeuchte = -6216.70 %
Was kann das sein?
Der Sensor ist in Ordung, an einer C-Control funktioniert er!!!
