Receiving Packet Array In Usart

[crhomberg]

Thanks Darryl,

You hit my problem on the spot, why are the small simplicities the ones that give the most grief?
I am going to look into hardware interrupts to allow me to break out of a serout2 command. Do you have any code that works well? If not, don't worry.
I feel I'm on the right track now.

Thanks All,

Chris

[Darrel Taylor]

I am going to look into hardware interrupts to allow me to break out of a serout2 command. Do you have any code that works well?

I ... uh ... er ... hem ... haw ...

Well, there's this ...

DT-INTS-14
http://www.darreltaylor.com/DT_INTS-14/intro.html
<br>

[skimask]

Thanks Darryl,
You hit my problem on the spot, why are the small simplicities the ones that give the most grief? I am going to look into hardware interrupts to allow me to break out of a serout2 command. Do you have any code that works well? If not, don't worry. I feel I'm on the right track now. Thanks All,
Chris

Or figure out a way you can send one byte at a time and check for an input in between bytes...

[crhomberg]

Tomorrow I want to try Darryl Taylor's instant interrups, I hope that will help.
When I removed or shortened the serout2 string all worked fine so I think if an assembler interrupt can stop the Serout2 before it completes things should work well. Even If I loose a few serout2 lines it is less important then loosing input packets.

Regards

Chris

[mister_e]

Pretty sure DarrEl's routine will help.

Nothing bad to wait between each character to send... kinda character pacing.. sort of.

[crhomberg]

Sorry Darrel for spelling your name wrong, I have only tried your blinky program so far but I am really impressed and exited.
Now I just have to do the same but with the interrupt from the USART receiver.

Thanks

[crhomberg]

Dear Darrel,

If you are still there, please read this adaption of my code to use your instant interrupts.
Something is still not right, it does not seem to get the values.

'************************************************* ***************

'JUST NEED TO SEND THE VALUE IN EACH BYTE ONCE THE PACKET HAS BEEN COLLECTED

'************************************************* ***************
'@ device hs_OSC, wdt_on, pwrt_on, protect_off
define osc 20
Include "modedefs.bas"
INCLUDE "DT_INTS-14.bas" ' Base Interrupt System
INCLUDE "ReEnterPBP.bas" ' Include if using PBP interrupts

trisc.6=0
TRISC.7=1
TRISA.0=0


RCSTA = %10010000 ' ENABLE USART AND SET TO CONTINUOUS RECEIVE
SPBRG = 64 'SET TO 4800bps
INTCON = %11000000 'ENABLE GLOBAL & PERIFERAL INTERRUPTS
RCIF VAR PIR1.5 'FLAG IS THE INTERRUPT WHEN A BYTE IS IN THE USART BUFFER
RCIE VAR PIE1.5
OERR VAR RCSTA.1
CREN VAR RCSTA.4
test var porta.0
BAUD CON 16390
start var bit

BUFFER VAR BYTE[8] 'BUFFER FROM USART TO COLLECT THE 8 BYTES
PELCO VAR BYTE[8]
BYTECOUNTER VAR BYTE 'USED TO COUNTER BYTES INTO THE BUFFER
BFULL VAR BIT 'FLAGS THAT THE BUFFER HAS ALL 8 BYTES
VALUE VAR BYTE 'A TEMP SINGLE BYTE RECEIVED FROM THE USART
COUNTER VAR WORD 'USED FOR LOOP IN MAIN PROGRAM
GOT VAR BIT 'USED TO PREVENT REPEATED SENDING OF SAME PACKET VIA SEROUT2

ASM
INT_LIST macro ; IntSource, Label, Type, ResetFlag? GOTO MAIN:
INT_Handler RX_INT, _GETDATA, PBP, yes
endm
INT_CREATE ; Creates the interrupt processor disable
ENDASM

@ INT_ENABLE RX_INT ; enable RX USART interrupts



PELCO=0
BUFFER = 0
BYTECOUNTER = 0
BFULL = 0
VALUE = 0
RCIE=1 'ENABLE USART RECEIVE INTERRUPT FLAG
GOT=0



'================================================= ====================================

MAIN:



if counter= 5000 THEN 'SEND PELCO VALUE EVERY FEW LOOPS

IF GOT=1 THEN 'IF THE PACKET IS NEW THEN SEND ELSE JUST KEEP LOOPING
serout2 test,BAUD,[HEX BUFFER[0],",",HEX BUFFER[1],",",HEX BUFFER[2],",",HEX BUFFER[3],",",HEX BUFFER[6],10,13] 'JUST CHECK 1ST 2 VALUES
GOT=0
ENDIF
toggle portd.1 'LED TO INDICATE TO ME THAT THE LOOP IS LOOPING
counter=0
else
counter=counter+1
endif

goto main

end


'====================INTERRUPT ROUTINE ==============================

GETDATA:

TOGGLE PORTD.0
IF RCIF=1 THEN

VALUE=RCREG
IF VALUE = $A0 THEN 'CHECK TO SEE IF THE BYTE IS THE START BYTE
BYTECOUNTER=0
ENDIF


IF BYTECOUNTER < 8 THEN
BUFFER[BYTECOUNTER] = VALUE 'ADD BYTE TO PACKET
BYTECOUNTER=BYTECOUNTER+1 'INCREMENT COUNTER
ENDIF

'CHECK IF OVERRUN HAS OCCURRED:

IF OERR=1 THEN
Serout2 test,BAUD,["OERR",10,13] 'TO SHOW OVERFLOW
PAUSE 1000
CREN=0 'STOP CONTINUOUS RECEIVE
CREN=1 'RESTART CONTINUOS RECIEVE & CLEAR THE OVERRUN FLAG
BYTECOUNTER=0 'RESET COUNTER AS PART OF PACKET HAS BEEN LOST SO START AGAIN
BUFFER=0
GOTO GETDATA
ENDIF

'*** PACKET MUST START WITH $A0 AND HAVE $AF AS IT'S 7TH BYTE. ******
IF BYTECOUNTER=7 AND BUFFER[0]=$A0 AND BUFFER[6]=$AF THEN
GOT=1 'INDICATE THAT THIS IS A NEW PACKET
GOTO MAIN 'RETURN TO MAIN PROGRAM
ELSE
GOTO GETDATA 'GO BACK AND WAIT FOR NEXT PACKET
ENDIF
ENDIF


@ INT_RETURN
'================================================= ====================================

[skimask]

Which PIC are you using?
(unless I missed something, I don't think that's ever been established...)

[Darrel Taylor]

Oh my, look what happened while I was out trying to make a buck, (a.k.a. at work).

That's the most "unless I missed something"'s I've ever seen in a row.

Chris,

You can't jump out of the Interrupt handler back to the main loop.
Instead, you should just use your GOT flag to indicate reception, then let the main loop handle it at it's leisure.

 IF BYTECOUNTER=7 AND BUFFER[0]=$A0 AND BUFFER[6]=$AF THEN
     GOT=1  'INDICATE THAT THIS IS A NEW PACKET                    
    GOTO MAIN   'RETURN TO MAIN PROGRAM
 ELSE
    GOTO GETDATA   'GO BACK AND WAIT FOR NEXT PACKET
 ENDIF
ENDIF
                
@ INT_RETURN

I think this might work better for the Main loop ...

MAIN:
    IF GOT=1 THEN  'IF THE PACKET IS NEW THEN SEND ELSE JUST KEEP LOOPING
        GOT=0
        GOSUB ShowBuffer
    ENDIF

    if counter= 5000 THEN 'SEND PELCO VALUE EVERY FEW LOOPS
        counter=0 
        GOSUB ShowBuffer
        toggle portd.1 'LED TO INDICATE TO ME THAT THE LOOP IS LOOPING
    ENDIF

    counter=counter+1
goto main


'==========================================================================
ShowBuffer:
    serout2 test,BAUD,[HEX BUFFER[0],",",HEX BUFFER[1],",",HEX BUFFER[2], _
    ",",HEX BUFFER[3],",",HEX BUFFER[6],10,13]  'JUST CHECK 1ST 2 VALUES
return

But, you'll still need to fix the Interrupt handler.

HTH,