I added DEFINE CHAR_PACING 2000
also 1000 works good with four $55
But it seems to be long to change the temperature, sometime the receiver seems to hang there with its value.
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I added DEFINE CHAR_PACING 2000
also 1000 works good with four $55
But it seems to be long to change the temperature, sometime the receiver seems to hang there with its value.
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HI, ok
I learned a lot in these four pages of posts,
What i did now I took the original program and modified it (serin, definnes, $55 , $aa ...
it works great now
I got a couple of glitches when I took the reciever down in the basement ( one floor below in a zig zag)
if you would like to see the code i could post it,
Last edited by lerameur; - 27th December 2006 at 21:25.
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Sure, maybe I can streamline it a bit or something...who knows...Originally Posted by lerameur
Then again...maybe I better not touch it! It works...leave it!
But seriously, I'll take a look...
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Those temp sensors aren't designed to respond to temp changes RIGHT NOW. If they did, they'd be all over the place. Remember, you have a certain amount of mass that you have to heat or cool and it takes X amount of time to do that, especially buried down in the middle of the blob of goo where the sensing element actually is. Fill a glass with ice cubes, fill the rest of the glass with water, let it sit for a bit, then dip the sensor in the water. It should read just a hair over, if not right on 0C/32F. You can add a bit of calibration by doing that. I don't think I'd try the boiling water for the other end though!
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well here goes,
I still need to do work, because I dont think it measures negatives temperature. Not sure yet how i am going to do it, but I will be
Transmitter:
'TRANSMIT PIC
INCLUDE "modedefs.bas"
DEFINE OSC 20 'use external 20mhz crystal
CMCON = 7 : ANSEL = 0 : ADCON1 = 7
DEFINE LCD_DREG PORTA ' Set LCD Data port
DEFINE LCD_DBIT 0 ' Set starting Data bit (0 or 4) if 4-bit bus
DEFINE LCD_RSREG PORTB ' Set LCD Register Select port
DEFINE LCD_RSBIT 1 ' Set LCD Register Select bit
DEFINE LCD_EREG PORTB ' Set LCD Enable port
DEFINE LCD_EBIT 0 ' Set LCD Enable bit
DEFINE LCD_BITS 4 ' Set LCD bus size (4 or 8 bits)
DEFINE LCD_LINES 2 ' Set number of lines on LCD
DEFINE LCD_COMMANDUS 2500
DEFINE LCD_DATAUS 250
DEFINE CHAR_PACING 2000
DQ var PortB.4
temp var word
temperature var word
count_remain var byte
count_per_c var byte
counter var byte
tempc var word
dataout var word
dataout2 var word
datain var word
array var word
encoded1 var word
encoded2 var word
encoded22 var word
encoded11 var word
loop:
owout DQ,1,[$cc]
owout DQ,0,[$44]
Pause 500
owout DQ,1,[$cc]
owout DQ,0,[$be]
owin DQ, 0, [temperature.LOwBYTE, temperature.Highbyte, Skip 4, count_remain, count_per_c]
'50
temperature = ((( temperature >> 1) *100)- 25) + (((count_per_c - count_remain) * 100) / count_per_c)
tempc = (((temperature *9) / 5)+3200)
dataout = temperature / 100
dataout2 = temperature
encoded1 =temperature.LowBYTE
encoded2 =temperature.HighBYTE
For counter=0 TO 7
IF encoded1.0[counter]=0 Then
encoded11.0[counter*2]=0
encoded11.0[counter*2+1]=1
Else
encoded11.0[counter*2]=1
encoded11.0[counter*2+1]=0
EndIF
Next counter
For counter=0 TO 7
IF encoded2.0[counter]=0 Then
encoded22.0[counter*2]=0
encoded22.0[counter*2+1]=1
Else
encoded22.0[counter*2]=1
encoded22.0[counter*2+1]=0
EndIF
Next counter
lcdout $FE,1
LCDOUT "TempC: ", dec (temperature / 100) , ".", dec2 temperature," ",$DF,"C"
lcdout $FE,$C0, bin encoded11.HighBYTE , ".", bin encoded2," ",$DF,"F"
serout portb.2, n2400, [$55, $55, $55, $55, $aa]
serout portb.2, n2400, [encoded22.HighBYTE, encoded22.LowBYTE, encoded11.HighBYTE, encoded11.LowBYTE ]
goto loop
End
Receiver:
'RECEIVE PIC
INCLUDE "modedefs.bas"
DEFINE OSC 20 'use external 20mhz crystal
CMCON = 7 : ANSEL = 0 : ADCON1 = 7
DEFINE LCD_DREG PORTA ' Set LCD Data port
DEFINE LCD_DBIT 0 ' Set starting Data bit (0 or 4) if 4-bit bus
DEFINE LCD_RSREG PORTB ' Set LCD Register Select port
DEFINE LCD_RSBIT 1 ' Set LCD Register Select bit
DEFINE LCD_EREG PORTB ' Set LCD Enable port
DEFINE LCD_EBIT 0 ' Set LCD Enable bit
DEFINE LCD_BITS 4 ' Set LCD bus size (4 or 8 bits)
DEFINE LCD_LINES 2 ' Set number of lines on LCD
DEFINE LCD_COMMANDUS 2500
DEFINE LCD_DATAUS 250
'16
datain2 var word :temp var word
datain var word
dataout var word
counter var byte
temperature var word
encoded1 var word
encoded2 var word
encoded11 var word
encoded22 var word
pause 2000
'28
loop:
waitfor55:
serin portb.2 , n2400 , temp : if temp <> $55 then goto waitfor55
waitforaa:
serin portb.2 , n2400 , temp : if temp <> $aa then goto waitforaa
'36
serin portb.2, n2400, encoded22.HighBYTE
serin portb.2, n2400, encoded22.LowBYTE
serin portb.2, n2400, encoded11.HighBYTE
serin portb.2, n2400, encoded11.LowBYTE
For counter=0 TO 7 'decoding
encoded1.0[counter]=encoded11.0[counter*2]
encoded2.0[counter]=encoded22.0[counter*2]
Next counter
temperature= encoded1 ' putting back together as the original temperature
For counter=0 TO 7
temperature.0[counter+8]=encoded2.0[counter+8]
Next counter
temperature.LowBYTE = encoded1
temperature.HighBYTE = encoded2
lcdout $FE,1
LCDOUT "TempC: ", dec (temperature / 100) , ".", dec2 temperature," ",$DF,"C"
lcdout $FE,$C0, bin encoded11.HighBYTE , ".", bin encoded2," ",$DF,"F"
goto loop
end
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Looks good enough. As far as handling the negative numbers, I'd do all the math at the receiving end, that way you can preserve the sign bit and work with it there rather than try to worry about how to transmit the sign bit along with the real temperature and screwing it up in the process.
The negative temperature is nothing more than using 2's complement math. Google it, re-read the -1820 datasheet. It's not that hard to handle those cases. It just takes a bit of creative math to work it out. And PBP can handle it if you work it right (hint: re-read the PBP manual, the SEROUT can handle 'signed' integers, make that work for you in the receiver code).
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hi, I have this simple if then statement, it givs me four mistakes.. It tells me I need and endif and also its abad expression , this is straight out of the pbp manual. what is wrong with it
IF temperature.bit11 = 1 Then zerotemp
zerotemp
program here
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If temperature.11 = 1 then goto zerotemp (don't need the goto but it always keeps me straight, and bit11 should work, but I just use 11 for no reason in particular)
zerotemp: (you didn't have a colon)
program here
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naa, i was initializing zerotemp dee.
I am going to put the calculation on the receiver side only, this is getting real confusing.
The reason i did not want to do that is I am sending 4 byte of coded information. I want to have a high accuracy, so i would like to send the count_per_c and count_remain and in the data sheet. that will add more bytes, If I take the raw information and send it, it will be 4 bytes or 8 encoded byte to send. Is this do able ?
I mean is it too much to send wireles ?
k
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