serial coms - again

[prstein]

This version will send only the target temperatures.
It should send "S" followed by carriage return
Then it should send 12 digits (4 sensors * 3 digits) followed by carriage return
It should then wait 3 seconds to give you time to process stuff, then it will query everything and expect all 108 characters back.
It will then wait 4 seconds, and display what it received

Instead, try:

It should send "S"(single character, no carriage return)
It should wait for the PIC to reply with "K" (or your favorite acknowledge character)
Then it should send 12 digits (4 sensors * 3 digits) followed by carriage return
It should then wait 3 seconds to give you time to process stuff, then it will query everything and expect all 108 characters back.
It will then wait 4 seconds, and display what it received

Then in your main loop add something like:
nTest var byte

If PIR1.5 = 1 Then 'check to see if there is data in the serial buffer
	HSERIN[nTest]
	if nTest = "S" then
		HSEROUT["K"]  'Let the PC know to start sending data
		HSERIN[....all the rest of your stuff...]
	endif
endif

I suspect the PIC appears to lock because it misses a byte. The above slows everything just a little and uses a positive acknowledgement to make sure everything is set.

Hope this helps somehow...

Best Regards,
Paul

[malc-c]

Paul,

Many thanks for the prompt reply.

One further question, in the original code there was the command to WRITE the result

WRITE Bvar, WORD SetPoints(EditChannel)

Would I need to use a similar line to update the normtemp variable with the data received from the PC, or will

Hserin [DEC3 normtemp(0)]
Hserin [DEC3 normtemp(1)]
Hserin [DEC3 normtemp(2)]
Hserin [DEC3 normtemp(3)]

suffice.

Also I'll add Bruce's time out as suggested, but should I also have the PIC send something at the end to tell the PC to signify data recived ?

[prstein]

Hello Malcom,

I confess the line "WRITE Bvar, WORD SetPoints(EditChannel)" doesn't make a lot of sense to me. I guess use it or not, depending on if you want non-volatile storage of the data. Just wait until *after* all the serial data is received as writing to the EEPROM takes (precious) time.

Regarding sending a final acknowledgement to the PC, I probably wouldn't bother if it was working well. Primarily because it can get complicated quickly between the PC program and PIC code, and it becomes extra frustrating if you are only writing one side and someone else is on the other.

Uncle Paul's general advice for serial ports:
0. Use the hardware USART/EUSART whenever possible. The software serial routines work well enough but are far trickier because there is no buffer.

1. Never try to read serial data until PIR1.5 = 1. Otherwise there is no data to be read and the firmware will hang. You can make this an interrupt source but I generally put it as an item in the main program loop.

2. Have the PC application send initially only 1 or 2 bytes of data to get the PIC's attention (because the PIC's serial buffer is 2 bytes so you are GUARANTEED to get that much successfully). Then the PC must patiently wait for the PIC to respond.

3. When the PIC is ready to receive the clump of data ("clump" means greater than two bytes), have it send a character or two back to the PC to signify "I'm ready."

4. After the PC receives the "I'm ready" message it should immediately send the data clump.

I don't work at all with VB or other forms of BASIC for the PC so I can't say anything specific about that. I generally use Delphi or C++, make use of the PC's multi-threading and serial buffer capabilities.

Hope I'm not missing the point here...8^)

Best Regards,
Paul

[malc-c]

Paul, thanks once again for the reply.

To simplify the testing between the applicatication this chap in Canada has written and my PBP code I've gone back to basics and written a simple test application that simply sends the output to the PC and then test the updating from the PC application.

;----[USART defines]--------------------------------------------------------
DEFINE HSER_RCSTA 90h                           ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 20h                           ' Enable transmit, BRGH = 0
DEFINE HSER_CLROERR 1                           ' Clear overflow automatically
DEFINE HSER_SPBRG 25                            ' 115200 Baud @ 48MHz, 0.16%
SPBRGH = 0
BAUDCON.3 = 1                                   ' Enable 16 bit baudrate generator
ColumnWidth CON 10


TempWD            VAR WORD
RCIF              VAR PIR1.5                    ' USART receive flag
GIE               VAR INTCON.7



alarmhigh         VAR WORD[4]                   ' used to store the desired high temp alarm values
    alarmhigh1       VAR alarmhigh[0]
    alarmhigh2       VAR alarmhigh[1]
    alarmhigh3       VAR alarmhigh[2]
    alarmhigh4       VAR alarmhigh[3]

alarmlow        VAR WORD[4]                   ' used to store the desired low temp alarm values
    alarmlow1       VAR alarmlow[0]
    alarmlow2       VAR alarmlow[1]
    alarmlow3       VAR alarmlow[2]
    alarmlow4       VAR alarmlow[3]


lightsetHR          VAR WORD[4]                 ' user to set light on hour  
  lightsetHR1       VAR lightsetHR[0]
  lightsetHR2       VAR lightsetHR[1]
  lightsetHR3       VAR lightsetHR[2]
  lightsetHR4       VAR lightsetHR[3] 
  
lightsetMN          VAR WORD[4]                   
  lightsetMN1       VAR lightsetMN[0]
  lightsetMN2       VAR lightsetMN[1]
  lightsetMN3       VAR lightsetMN[2]
  lightsetMN4       VAR lightsetMN[3]  
  
lightoffHR          VAR WORD[4]                   
  lightoffHR1       VAR lightoffHR[0]
  lightoffHR2       VAR lightoffHR[1]
  lightoffHR3       VAR lightoffHR[2]
  lightoffHR4       VAR lightoffHR[3] 
  
lightoffMN          VAR WORD[4]                   
  lightoffMN1       VAR lightoffMN[0]
  lightoffMN2       VAR lightoffMN[1]
  lightoffMN3       VAR lightoffMN[2]
  lightoffMN4       VAR lightoffMN[3]    

StartHour	         VAR WORD[4] 
  StartHour1         VAR StartHour[0]
  StartHour2         VAR StartHour[1]
  StartHour3         VAR StartHour[2]
  StartHour4         VAR StartHour[3]
  
StartMin             VAR WORD[4]  
  StartMin1          VAR StartMin[0]
  StartMin2          VAR StartMin[1]
  StartMin3          VAR StartMin[2]
  StartMin4          VAR StartMin[3]

StopHour   	         VAR WORD[4]
  StopHour1          VAR StopHour[0]
  StopHour2          VAR StopHour[1]
  StopHour3          VAR StopHour[2]
  StopHour4          VAR StopHour[3]
  
StopMin     	     VAR WORD[4]  
  StopMin1           VAR StopMin[0]
  StopMin2           VAR StopMin[1]
  StopMin3           VAR StopMin[2]
  StopMin4           VAR StopMin[3]

Droptemp	     VAR WORD[4]  
droptemp1     var Droptemp[0]
droptemp2       var Droptemp[1]
droptemp3       var Droptemp[2]
droptemp4       var Droptemp[3]                

Temperatures      VAR WORD[4]
  Temp1           VAR Temperatures[0]
  Temp2           VAR Temperatures[1]
  Temp3           VAR Temperatures[2]
  Temp4           VAR Temperatures[3]
  
  
SetPoints         VAR WORD[4]                   ' used to store the desired temperature setting
  SetPoint1       VAR SetPoints[0]
  SetPoint2       VAR SetPoints[1]
  SetPoint3       VAR SetPoints[2]
  SetPoint4       VAR SetPoints[3]
  
normtemp          VAR WORD[4]                   ' used to store the desired temperature setting
  normtemp1       VAR normtemp[0]
  normtemp2       VAR normtemp[1]
  normtemp3       VAR normtemp[2]
  normtemp4       VAR normtemp[3]  

FlashStar         VAR BIT 
nTest var byte
;---------------------------------------------------------------------
 
;set test values

Temperatures[0]=230
Temperatures[1]=240
Temperatures[2]=250
Temperatures[3]=260
  
normtemp[0]=240
normtemp[1]=250
normtemp[2]=260
normtemp[3]=270

alarmlow[0]=180
alarmlow[1]=180
alarmlow[2]=180
alarmlow[3]=180

alarmhigh[0]=360
alarmhigh[1]=360
alarmhigh[2]=360
alarmhigh[3]=360

StartHour1=00
StartHour2=00
StartHour3=00
StartHour4=00

StartMin1=00
StartMin2=00
StartMin3=00
StartMin4=00

StopHour1=00
StopHour2=00
StopHour3=00
StopHour4=00

StopMin1=00
StopMin2=00
StopMin3=00
StopMin4=00

Droptemp[0]=180  
Droptemp[1]=180 
Droptemp[2]=180 
Droptemp[3]=180

lightsetHR1=00
lightsetHR2=00
lightsetMN1=00
lightsetMN2=00
  
lightoffHR1=00
lightoffHR2=00
lightoffMN1=00
lightoffMN2=00
  

  ;______________________________________________________________

main:


If PIR1.5 = 1 Then 'check to see if there is data in the serial buffer
	HSERIN[nTest]
	if nTest = "S" then
gosub Term_RX
	endif
endif

  
for tempwd = 0 to 3
setpoints(tempwd)=normtemp(tempwd)
next 
   
    
LCDOut $FE,$D4+8,#setpoints(0)dig 2,#setpoints(0)dig 1,$FE,$D4+11,#setpoints(1)dig 2,#setpoints(1)dig 1  ' show current set temperatures
LCDOut $FE,$D4+14,#setpoints(2)dig 2,#setpoints(2)dig 1,$FE,$D4+17,#setpoints(3)dig 2,#setpoints(3)dig 1 
LCDOUT $FE,$80 + 18,("*"&FlashStar*$FF)|(" "&~(FlashStar*$FF)) ; flash a star to show sample time, but used to indicate Alarm settings monitored
    FlashStar = !FlashStar 


Hserout [DEC3 Temperatures[0]]
Hserout [DEC3 Temperatures[1]]
Hserout [DEC3 Temperatures[2]]
Hserout [DEC3 Temperatures[3]]

HSEROUT [dec3 normtemp[0]]
HSEROUT [dec3 normtemp[1]]
HSEROUT [dec3 normtemp[2]]
HSEROUT [dec3 normtemp[3]]

Hserout [dec3 alarmlow[0]]
Hserout [dec3 alarmlow[1]]
Hserout [dec alarmlow[2]]
Hserout [dec alarmlow[3]]

Hserout [dec3 alarmhigh[0]]
Hserout [dec3 alarmhigh[1]]
Hserout [dec3 alarmhigh[2]]
Hserout [dec3 alarmhigh[3]]

hserout [#StartHour[0] DIG 1,#StartHour[0] DIG 0,#StartMin[0] DIG 1,#StartMin[0] DIG 0]
hserout [#StartHour[1] DIG 1,#StartHour[1] DIG 0,#StartMin[1] DIG 1,#StartMin[1] DIG 0]
hserout [#StartHour[2] DIG 1,#StartHour[2] DIG 0,#StartMin[2] DIG 1,#StartMin[2] DIG 0]
hserout [#StartHour[3] DIG 1,#StartHour[3] DIG 0,#StartMin[3] DIG 1,#StartMin[3] DIG 0]

hserout [#StopHour[0] DIG 1,#StopHour[0] DIG 0,#StopMin[0] DIG 1,#StopMin[0] DIG 0]
hserout [#StopHour[1] DIG 1,#StopHour[1] DIG 0,#StopMin[1] DIG 1,#StopMin[1] DIG 0]
hserout [#StopHour[2] DIG 1,#StopHour[2] DIG 0,#StopMin[2] DIG 1,#StopMin[2] DIG 0]
hserout [#StopHour[3] DIG 1,#StopHour[3] DIG 0,#StopMin[3] DIG 1,#StopMin[3] DIG 0]

Hserout [dec3 Droptemp[0]]
Hserout [dec3 Droptemp[1]]
Hserout [dec3 Droptemp[2]]
Hserout [dec3 Droptemp[3]]

hserout [#lightsetHR[0] DIG 1,#lightsetHR[0] DIG 0,#lightsetMN[0] DIG 1,#lightsetMN[0] DIG 0]
hserout [#lightsetHR[1] DIG 1,#lightsetHR[1] DIG 0,#lightsetMN[1] DIG 1,#lightsetMN[1] DIG 0]


hserout [#lightoffHR[0] DIG 1,#lightoffHR[0] DIG 0,#lightoffMN[0] DIG 1,#lightOFFMN[0] DIG 0]
hserout [#lightoffHR[1] DIG 1,#lightoffHR[1] DIG 0,#lightoffMN[1] DIG 1,#lightOFFMN[1] DIG 0]

pause 200

goto main


Term_RX:
HSERin [dec3 normtemp[0]]
return

The application is simply sending S followed by three digits for normtemp[0] in DEC format, with no carriage returns - However when I click the update button of the application the PIC freezes for around 10 min. I've proved the PIC is responding to the PC app by changing the "S" to "X" (or any other character) which is ignored when the update button is pressed.

Unfortunately given the time difference (I'm in the UK he's in Canada) the logistics of implementing the suggestions of handshaking the way you suggest is not forthcoming.

Any suggestions

[prstein]

Hi Malcom,

Try changing the end of your code to this:

Term_RX:
	TempWD = 0
	HSERIN 1000,RX_Bombed,[DEC3 TempWD]
	normtemp[0] = TempWD
	RETURN
RX_Bombed:
	HSEROUT ["Term_RX bombed out, all we got was", dec TempWD,13,10]
return

This should at least provide some insight into what's going on inside the PIC.

In your test application you ought to put a pause of at least 10 msec or so between when the "S" and the rest of the data are sent. You could also probably test this using the Serial Communicator inside of MicroCode Studio, if you have that. Hyperterm would also work.

I couldn't find your OSC define in this thread. Which oscillator speed are you using?

Oh, and DOH! I just recalled that I think you "terminate" the DEC3 by sending something that isn't a numeric ASCII character. Try sending a carriage return or a line feed after the 3-character value.

Best Regards,
Paul

[malc-c]

This is really doing my head in... My friends application simply sends Q on launch, and the S+three digits representing the new value for just one variable followed by Q. Yet I keep getting incorrect values in the receive variable.

Here's the test code. For testing purpose all the values for each variable is fixed to populate his PC application. The only variable that is updated is the Target Temperature for Unit 1.

ASM 
  __CONFIG    _CONFIG1H, _OSC_HSPLL_1H
  __CONFIG    _CONFIG2L, _PWRT_ON_2L  
  __CONFIG    _CONFIG2H, _WDT_ON_2H & _WDTPS_512_2H
  __CONFIG    _CONFIG3H, _PBADEN_OFF_3H
  __CONFIG    _CONFIG4L, _LVP_OFF_4L & _XINST_OFF_4L
ENDASM


DEFINE OSC 48                     ; uses 12Mhz xtal

ADCON1 = $0F
clear

DEFINE LCD_DREG  PORTB           ' LCD Data port
DEFINE LCD_DBIT  0               ' starting Data bit (0 or 4)
DEFINE LCD_EREG  PORTB           ' LCD Enable port
DEFINE LCD_EBIT  5               '     Enable bit  (on EasyPIC 5 LCD)
DEFINE LCD_RSREG PORTB           ' LCD Register Select port
DEFINE LCD_RSBIT 4               '     Register Select bit   (on EasyPIC 5 LCD)
DEFINE LCD_BITS  4               ' LCD bus size (4 or 8 bits)
DEFINE LCD_LINES 4               ' number of lines on LCD
DEFINE LCD_COMMANDUS 2000        ' Command delay time in us 
DEFINE LCD_DATAUS 50             ' Data delay time in us 


;----[Port settings]----------------------------------------------------

TRISA = %11001111
TRISB = %00000000
TRISD = %00001111
CMCON = 7                                       ' disable Comparators

;----[USART defines]--------------------------------------------------------
DEFINE HSER_RCSTA 90h                           ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 20h                           ' Enable transmit, BRGH = 0
DEFINE HSER_CLROERR 1                           ' Clear overflow automatically
DEFINE HSER_SPBRG 25                            ' 115200 Baud @ 48MHz, 0.16%
SPBRGH = 0
BAUDCON.3 = 1                                   ' Enable 16 bit baudrate generator
ColumnWidth CON 10


TempWD            VAR WORD
RCIF              VAR PIR1.5                    ' USART receive flag
GIE               VAR INTCON.7

tr var byte

alarmhigh         VAR WORD[4]                   ' used to store the desired high temp alarm values
    alarmhigh1       VAR alarmhigh[0]
    alarmhigh2       VAR alarmhigh[1]
    alarmhigh3       VAR alarmhigh[2]
    alarmhigh4       VAR alarmhigh[3]

alarmlow        VAR WORD[4]                   ' used to store the desired low temp alarm values
    alarmlow1       VAR alarmlow[0]
    alarmlow2       VAR alarmlow[1]
    alarmlow3       VAR alarmlow[2]
    alarmlow4       VAR alarmlow[3]


lightsetHR          VAR WORD[4]                 ' user to set light on hour  
  lightsetHR1       VAR lightsetHR[0]
  lightsetHR2       VAR lightsetHR[1]
  lightsetHR3       VAR lightsetHR[2]
  lightsetHR4       VAR lightsetHR[3] 
  
lightsetMN          VAR WORD[4]                   
  lightsetMN1       VAR lightsetMN[0]
  lightsetMN2       VAR lightsetMN[1]
  lightsetMN3       VAR lightsetMN[2]
  lightsetMN4       VAR lightsetMN[3]  
  
lightoffHR          VAR WORD[4]                   
  lightoffHR1       VAR lightoffHR[0]
  lightoffHR2       VAR lightoffHR[1]
  lightoffHR3       VAR lightoffHR[2]
  lightoffHR4       VAR lightoffHR[3] 
  
lightoffMN          VAR WORD[4]                   
  lightoffMN1       VAR lightoffMN[0]
  lightoffMN2       VAR lightoffMN[1]
  lightoffMN3       VAR lightoffMN[2]
  lightoffMN4       VAR lightoffMN[3]    

StartHour	         VAR WORD[4] 
  StartHour1         VAR StartHour[0]
  StartHour2         VAR StartHour[1]
  StartHour3         VAR StartHour[2]
  StartHour4         VAR StartHour[3]
  
StartMin             VAR WORD[4]  
  StartMin1          VAR StartMin[0]
  StartMin2          VAR StartMin[1]
  StartMin3          VAR StartMin[2]
  StartMin4          VAR StartMin[3]

StopHour   	         VAR WORD[4]
  StopHour1          VAR StopHour[0]
  StopHour2          VAR StopHour[1]
  StopHour3          VAR StopHour[2]
  StopHour4          VAR StopHour[3]
  
StopMin     	     VAR WORD[4]  
  StopMin1           VAR StopMin[0]
  StopMin2           VAR StopMin[1]
  StopMin3           VAR StopMin[2]
  StopMin4           VAR StopMin[3]

Droptemp	     VAR WORD[4]  
droptemp1     var Droptemp[0]
droptemp2       var Droptemp[1]
droptemp3       var Droptemp[2]
droptemp4       var Droptemp[3]                 ; these will be set via pots 

Temperatures      VAR WORD[4]
  Temp1           VAR Temperatures[0]
  Temp2           VAR Temperatures[1]
  Temp3           VAR Temperatures[2]
  Temp4           VAR Temperatures[3]
  
spModes           VAR BYTE[4]                   ' controls how set point is adjusted PC or POT
  spMode1         VAR spModes[0]
  spMode2         VAR spModes[1]
  spMode3         VAR spModes[2]
  spMode4         VAR spModes[3]
  
SetPoints         VAR WORD[4]                   ' used to store the desired temperature setting
  SetPoint1       VAR SetPoints[0]
  SetPoint2       VAR SetPoints[1]
  SetPoint3       VAR SetPoints[2]
  SetPoint4       VAR SetPoints[3]
  
normtemp          VAR WORD[4]                   ' used to store the desired temperature setting
  normtemp1       VAR normtemp[0]
  normtemp2       VAR normtemp[1]
  normtemp3       VAR normtemp[2]
  normtemp4       VAR normtemp[3]  

FlashStar         VAR BIT 
nTest var byte
temphold var byte
temp var byte
;---------------------------------------------------------------------
 
;set test values

Temperatures[0]=230
Temperatures[1]=240
Temperatures[2]=250
Temperatures[3]=260
  
normtemp[0]=240
normtemp[1]=250
normtemp[2]=260
normtemp[3]=270

alarmlow[0]=180
alarmlow[1]=180
alarmlow[2]=180
alarmlow[3]=180

alarmhigh[0]=360
alarmhigh[1]=360
alarmhigh[2]=360
alarmhigh[3]=360

StartHour1=00
StartHour2=00
StartHour3=00
StartHour4=00

StartMin1=00
StartMin2=00
StartMin3=00
StartMin4=00

StopHour1=00
StopHour2=00
StopHour3=00
StopHour4=00

StopMin1=00
StopMin2=00
StopMin3=00
StopMin4=00

Droptemp[0]=180  
Droptemp[1]=180 
Droptemp[2]=180 
Droptemp[3]=180

lightsetHR1=00
lightsetHR2=00
lightsetMN1=00
lightsetMN2=00
  
lightoffHR1=00
lightoffHR2=00
lightoffMN1=00
lightoffMN2=00
  

  ;______________________________________________________________

main:

FOR TempWD = 0 TO 1000
IF RCIF=1 THEN GOSUB Term_RX       
PAUSE 2
NEXT TempWD


setpoints(0)=normtemp(0)


  
LCDOut $FE,$D4,#setpoints(0)dig 2,#setpoints(0)dig 1,#setpoints(0)dig 0
    FlashStar = !FlashStar 
pause 200
goto main

send:
Hserout [DEC3 Temperatures[0]]
Hserout [DEC3 Temperatures[1]]
Hserout [DEC3 Temperatures[2]]
Hserout [DEC3 Temperatures[3]]

HSEROUT [dec3 normtemp[0]]
HSEROUT [dec3 normtemp[1]]
HSEROUT [dec3 normtemp[2]]
HSEROUT [dec3 normtemp[3]]

Hserout [dec3 alarmlow[0]]
Hserout [dec3 alarmlow[1]]
Hserout [dec alarmlow[2]]
Hserout [dec alarmlow[3]]

Hserout [dec3 alarmhigh[0]]
Hserout [dec3 alarmhigh[1]]
Hserout [dec3 alarmhigh[2]]
Hserout [dec3 alarmhigh[3]]

hserout [#StartHour[0] DIG 1,#StartHour[0] DIG 0,#StartMin[0] DIG 1,#StartMin[0] DIG 0]
hserout [#StartHour[1] DIG 1,#StartHour[1] DIG 0,#StartMin[1] DIG 1,#StartMin[1] DIG 0]
hserout [#StartHour[2] DIG 1,#StartHour[2] DIG 0,#StartMin[2] DIG 1,#StartMin[2] DIG 0]
hserout [#StartHour[3] DIG 1,#StartHour[3] DIG 0,#StartMin[3] DIG 1,#StartMin[3] DIG 0]

hserout [#StopHour[0] DIG 1,#StopHour[0] DIG 0,#StopMin[0] DIG 1,#StopMin[0] DIG 0]
hserout [#StopHour[1] DIG 1,#StopHour[1] DIG 0,#StopMin[1] DIG 1,#StopMin[1] DIG 0]
hserout [#StopHour[2] DIG 1,#StopHour[2] DIG 0,#StopMin[2] DIG 1,#StopMin[2] DIG 0]
hserout [#StopHour[3] DIG 1,#StopHour[3] DIG 0,#StopMin[3] DIG 1,#StopMin[3] DIG 0]

Hserout [dec3 Droptemp[0]]
Hserout [dec3 Droptemp[1]]
Hserout [dec3 Droptemp[2]]
Hserout [dec3 Droptemp[3]]

hserout [#lightsetHR[0] DIG 1,#lightsetHR[0] DIG 0,#lightsetMN[0] DIG 1,#lightsetMN[0] DIG 0]
hserout [#lightsetHR[1] DIG 1,#lightsetHR[1] DIG 0,#lightsetMN[1] DIG 1,#lightsetMN[1] DIG 0]


hserout [#lightoffHR[0] DIG 1,#lightoffHR[0] DIG 0,#lightoffMN[0] DIG 1,#lightOFFMN[0] DIG 0]
hserout [#lightoffHR[1] DIG 1,#lightoffHR[1] DIG 0,#lightoffMN[1] DIG 1,#lightOFFMN[1] DIG 0]



return

Term_RX:
    HSERIN[nTest]
    SELECT CASE nTest
    CASE "S"
            HSERIN [normtemp[0]]
            setpoints(0)=normtemp[0]
    END SELECT
    gosub send    
return

On booting the PIC it displays the value of normtemp[0] as 240 on the LCD. I've used a serial port monitor and when the application is launched the port sniffer confirms that Q was sent and the PIC dumped the string of values to the port, which the application pics up and populates the text boxes correctly.



The application has been written to allow the user to enter the desired target temperature directly in the associated text box as required such as 45.2 and then click on the UPDATE button. This then sends S followed by the new value as a three digit number in the same format as the PBP code. This can be confirmed by the port sniffer



However, the LCD display then reads 052, and this is then sent back to the PC application (as can be seen if you follow through the digits in the com sniffer top window.



I think by fluke I did manage to get it to work once where the normtemp[0] variable was correctly updated, but that was after a restart of both the windows application and the PIC. What's been suggested is that I need the PBP code to check that the PICs buffer is empty, but I'm not sure on how to best do that.

Eventually we need to be able to update all the values in the rest of the boxes, and it my understanding my friends application will simply send all the values back in one data stream that will match the same as that transmitted (less the first 12 digits as it doesn't need to update the current temperatures - this is a one way transmission from the PIC). Thus the RX section will have HSERIN for each variables as per the HSEROUT section - will this compound the problem or can someone suggest a better way of doing this.

[HenrikOlsson]

Hi Malcolm,
I think you need to do:

HSERIN [DEC3 NORMTEMP[0]]

/Henrik.

EDIT: Look at post #22 up above, Paul's already covered it, are you saying that IT isn't working either?