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Bootloader

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LOL yeah :

Im trying the Microchip code and it sux i had to add/edit:
Code: 
	LIST P=18F2525
	#include P18F2525.INC		; Standard include

;/// AtomSoftTech additions
#define RCREG1 RCREG
#define TXREG1 TXREG

#define RCSTA1 RCSTA
#define TXSTA1 TXSTA

#define SPBRG1 SPBRG
;/// end of additions

Just for it to compile
 
Is you chip not one of the ones supported by the bootloader ?

There is most possibly a list of chips and ifdef code in the asm source or header files that should take care of these defines.

Either your chip is not supported or you have neglected to edit some configuration info. Given that the code works with a number chips these ifdefs must exist somewhere.
 
not sure lol but will look

I think the bootload is working ... it shows up in the windows program but i need to create a sample program now to download to it via rs232
 
Last edited:
Im going to try to make my own from scratch in C18 lol because this is killing me. I know one of the most important parts is communication of UART so i set that up first for 9600bps.

Code: 
#include <p18f2525.h>

#pragma config WDT = OFF, LVP = OFF, OSC = INTIO67, XINST = OFF

unsigned char buff[11];

void main(void);
void initUART(void);

void initUART(void){

    SPBRGH = 0;
    SPBRG = 51;
    TXSTAbits.BRGH = 1;
    TXSTAbits.SYNC = 0;
    BAUDCONbits.BRG16 = 0;

    RCSTAbits.SPEN = 1;
    TXSTAbits.TXEN = 1;
    
    PIR1bits.TXIF = 0;

    RCSTAbits.SREN = 0;
    RCSTAbits.CREN = 1;

    PIR1bits.RCIF =0;    

    TRISCbits.TRISC7 = 1;
    TRISCbits.TRISC6 = 1;

}
unsigned char ReadRx(void){
    while(PIR1bits.RCIF == 0);

    PIR1bits.RCIF = 0; 
    return RCREG;
}
void SendTx(unsigned char data){
    TXREG = data;
}

void main(void){
	unsigned char x;

	OSCCON = 0x72;      		//8MHz clock
	while(!OSCCONbits.IOFS);	//Wait for osc stable

    initUART();

	while(1){
        for(x=0x20;x<0x7b;x++){
            SendTx(x);
            Delay1KTCYx(200);
        }
        for(x=0;x<11;x++){
            buff[x] = ReadRx();
        }
        
	}
}

EDIT: Now has polling Receive UART code. Works 100% so far lol just uart tho lol
 
Last edited:
AtomSoft said:
1 question before i start also...

Those USB to SERIAL by FTDI can be used for this also right? I mean all you would have to do is setup the COM on the PC side since its a Virtual Com port right?
Click to expand...
Once you get past the bootloader issue, then no need for the FTDI at all, If I understood your question correctly.

As total noob to USB, have just run a few precompiled examples from the Microchip Solutions folder which may have come from the latest USB framework download, I forget. Anyway there is a USB MCHPUSB Generic Driver Demo folder in there, that sends and receives simple I/O commands using a simple VB form, no FTDI serial to USB about it.

Someday, a wireless USB temp guage hehe.
 
Yikes, can't keep my numbers or facts straight:eek:

Well if you ever get the USB bug:), not sure If I've got it or not:rolleyes:, more investigation required.
 
The only issue is it takes the first 2 seconds of the product start time to enter debug if wanted. Which sucks! i rather have a special line or button to enable it upon reset. Like

If prog button is high when startup then enter program/boot mode.

EDIT:
Also found out that the 18F2525 comes with a 2k bootblock. so it has to start at 0x0800
 
Last edited:
OMG wtf lol.. I see my UART isnt working in ASM thats why it wasnt working before:

My C18 UART code:
Code: 
#include <p18f2525.h>

#pragma config WDT = OFF, LVP = OFF, OSC = INTIO67, XINST = OFF
//.................
//.........................
	OSCCON = 0x72;      		//8MHz clock
	while(!OSCCONbits.IOFS);	//Wait for osc stable
//..................................

    SPBRGH = 0;
    SPBRG = 51;
    TXSTAbits.BRGH = 1;
    TXSTAbits.SYNC = 0;
    BAUDCONbits.BRG16 = 0;

    RCSTAbits.SPEN = 1;
    TXSTAbits.TXEN = 1;
    
    PIR1bits.TXIF = 0;

    RCSTAbits.SREN = 0;
    RCSTAbits.CREN = 1;

    PIR1bits.RCIF =0;    

    TRISCbits.TRISC7 = 1;
    TRISCbits.TRISC6 = 1;

My ASM uart code:
Code: 
	LIST P=18F2525
	#include P18F2525.inc
	CONFIG WDT = OFF, LVP = OFF, OSC = INTIO67, XINST = OFF

;.................
;.........................
Setup
	movlw	0x72
	movlw	OSCCON
	btfss	OSCCON,IOFS
	bra		$-2
;..................................

Autobaud
	bcf		RCSTA, SPEN
	bcf		TXSTA, TXEN

	clrf	SPBRGH
	movlw	D'51'
	movwf	SPBRG
	bsf		TXSTA, BRGH
	bcf		TXSTA, SYNC
	bcf		BAUDCON, BRG16

	bsf		RCSTA, SPEN
	bsf		TXSTA, TXEN

	bcf		PIR1, TXIF
	
	bcf		RCSTA, SREN
	bsf		RCSTA, CREN

	bcf		PIR1, RCIF

	bsf		TRISC, 7
	bsf		TRISC, 6


How come the C code works fine and the ASM doesnt?
 
Last edited:
Jason,

What is that "lol" you use so often?
 
its like a laugh but the crazy mad type. Like i wanna smash something psyco laugh .... sometimes lol (laugh out loud)

i might use COL from now on lol (cryin out loud)
 
Last edited:
but im trying to use Serial. If i use USB then i have to use the 2550 or similar. Which would limit my PIC choices. If i use serial then i can use any pic and later on convert to USB using a FTDI IC
 
AtomSoft said:
but im trying to use Serial. If i use USB then i have to use the 2550 or similar. Which would limit my PIC choices. If i use serial then i can use any pic and later on convert to USB using a FTDI IC
Click to expand...

Sorry, but serial is pretty well dead - new computers generally don't even have serial ports.
 
heh its ok lol

Get ready to laugh ... i fixed the UART issue:
Code: 
	movlw	0x72 
	movlw	OSCCON ;[b]movlw[/b]

supposed to be:
Code: 
	movlw	0x72 
	movwf	OSCCON ;[b]movlw[/b]
 
Here is the full code for bootloader for 18F2525 Using AN851 program.

Program Button is RB0 when HIGH it will enter BOOTLOAD MODE
Code: 
; *****************************************************************************
;        Software License Agreement				    
;		 			 			    
; The software supplied herewith by Microchip Technology 	    
; Incorporated (the “Company”) for its PICmicro® Microcontroller is 
; intended and supplied to you, the Company’s customer, for use     
; solely and exclusively on Microchip PICmicro Microcontroller	    
; products. The software is owned by the Company and/or its         
; supplier, and is protected under applicable copyright laws. All   
; rights are reserved. Any use in violation of the foregoing 	     
; restrictions may subject the user to criminal sanctions under	    
; applicable laws, as well as to civil liability for the breach of  
; the terms and conditions of this license.			    
;								    
; THIS SOFTWARE IS PROVIDED IN AN “AS IS” CONDITION. NO WARRANTIES, 
; WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED 
; TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 	    
; PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT, 
; IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR 	    
; CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.		    
;		 						    
;					 			    
; Bootloader for PIC18F by Ross Fosler 
; 09/1/2006     Modified to support PIC18xxJxx & 160k PIC18Fxxx Flash Devices
; 03/01/2002	... First full implementation
; 03/07/2002	Changed entry method to use last byte of EEDATA.
;		Also removed all possible infinite loops w/ clrwdt.
; 03/07/2002	Added code for direct boot entry. I.E. boot vector.
; 03/09/2002	Changed the general packet format, removed the LEN field.
; 03/09/2002	Modified the erase command to do multiple row erase.
; 03/12/2002	Fixed write problem to CONFIG area. Write was offset by a byte.
; 03/15/2002	Added work around for 18F8720 tblwt*+ problem.
; 03/20/2002	Modified receive & parse engine to vector to autobaud on a checksum 
;		error since a chechsum error could likely be a communications problem.
; 03/22/2002 	Removed clrwdt from the startup. This instruction affects the TO and 
;		PD flags. Removing this instruction should have no affect on code 
;		operation since the wdt is cleared on a reset and boot entry is always
;		on a reset.
; 03/22/2002	Modified the protocol to incorporate the autobaud as part of the 
;		first received <STX>. Doing this improves robustness by allowing
;		re-sync under any condition. Previously it was possible to enter a 
;		state where only a hard reset would allow re-syncing.
; 03/27/2002	Removed the boot vector and related code. This could lead to customer
;		issues. There is a very minute probability that errent code execution
;		could jump into the boot area and cause artificial boot entry.
;
; Memory Map
;	-----------------
;	|    0x0000		|
;	|    0x0002    	|	Boot vector
;   |    0x0004		|	Unlock & write vector
;	|    			|	
;	|				|
;	|  Boot Block 	|  	(this program)
; 	|				|   (PIC18Fxxx Devices)
;	|    0x0200		|		Re-mapped Reset Vector
;	|    0x0208		|		Re-mapped High Priority Interrupt Vector
;	|    0x0218		|		Re-mapped Low Priority Interrupt Vector
;	|				|   
;	|				|	(PIC18FxxJxx Devices)
;	|	 0x0400		|		Re-mapped Reset Vector
;	|    0x0408		|		Re-mapped High Priority Interrupt Vector
;	|    0x0418		|		Re-mapped Low Priority Interrupt Vector
;	|				|
;   |  Code Space 	|	User program space
;	|				|
;	|				|
;	|				|
;	|   0xXXXXXX    |
;	-----------------
;
;
; Incomming data format:
;
;	<STX><STX><DATA><CHKSUM><ETX>
;		  /    \
;	 ________/      \____________________________
;	/	                                     \
;	<COMMAND><DLEN><ADDRL><ADDRH><ADDRU><DATA>...
;
; Definitions:
;
; 	STX	-	Start of packet indicator
;	ETX	-	End of packet indicator
; 	LEN 	-	Length of incomming packet
; 	DATA	-	General data up to 255 bytes
; 	CHKSUM 	- 	The 8-bit two's compliment sum of LEN & DATA
; 	COMMAND - 	Base command
; 	DLEN	-	Length of data associated to the command
; 	ADDR	-	Address up to 24 bits
; 	DATA 	-	Data (if any)
;
;
; Commands:
;
; 	RD_VER		0x00	Read Version Information
; 	RD_MEM		0x01	Read Program Memory
; 	WR_MEM		0x02	Write Program Memory
; 	ER_MEM		0x03	Erase Program Memory
; 	RD_EE		0x04	Read EEDATA Memory 
; 	WR_EE		0x05	Write EEDATA Memory 
; 	RD_CONFIG	0x06	Read Config Memory 
; 	WT_CONFIG	0x07	Write Config Memory 
;
; *****************************************************************************

 

; *****************************************************************************
	;#include P18F452.INC		; Standard include
	;#include P18F8720.inc
	;#include P18F8622.inc
	;#include P18f67J10.inc
	;#include P18F8722.inc
	;#include J_Defines.inc
	;#include 64byte_Defines.inc
; *****************************************************************************
	LIST P=18F2525
	#include P18F2525.inc
	#include 64byte_Defines.inc
; *****************************************************************************
	CONFIG WDT = OFF, LVP = OFF, OSC = INTIO67, XINST = OFF

#define RCREG1 RCREG
#define TXREG1 TXREG

#define RCSTA1 RCSTA
#define TXSTA1 TXSTA

#define SPBRG1 SPBRG
#define ProgBtn 0
#define ProgBtnT TRISB
#define ProgBtnP PORTB

; *****************************************************************************

#define	MINOR_VERSION	0x0C		; Version
#define	MAJOR_VERSION	0x00

#define	RC_DLE		0x01
#define	RC_STX		0x02

#define	STX		0x0F
#define	ETX		0x04
#define	DLE		0x05

;#define	TBLWT_BUG			; Timing bug found in some PIC18Fxx20s
; *****************************************************************************



; *****************************************************************************
CHKSUM		equ	0x00		; Checksum accumulator
COUNTER		equ	0x01		; General counter
ABTIME_H	equ	0x02
ABTIME_L	equ	0x03
RXDATA		equ	0x04
TXDATA		equ	0x05
J_PACKET_COUNTER equ 0x6

; Frame Format
;
;  <STX><STX>[<COMMAND><DATALEN><ADDRL><ADDRH><ADDRU><...DATA...>]<CHKSUM><ETX>

DATA_BUFF	equ	0x08		; Start of receive buffer
	
COMMAND		equ	0x08		; Data mapped in receive buffer
DATA_COUNT	equ	0x09	
ADDRESS_L	equ	0x0A
ADDRESS_H	equ	0x0B
ADDRESS_U	equ	0x0C
PACKET_DATA	equ	0x0D

	
; *****************************************************************************




; *****************************************************************************
pmwtpi macro				; tblwt*+ macro for PIC18Fxx20 bug
 IFDEF TBLWT_BUG
	tblwt	*
	tblrd	*+
 ELSE
	tblwt	*+
 ENDIF
	endm
; *****************************************************************************


 
; *****************************************************************************
	ORG	0x0000			; Re-map Reset vector
	bra	Setup	
	bra	StartWrite
	

	ORG	0x0008
VIntH
	bra	RVIntH			; Re-map Interrupt vector

	ORG	0x0018
VIntL
	bra	RVIntL			; Re-map Interrupt vector
; *****************************************************************************

 

; *****************************************************************************
; Setup the appropriate registers.
Setup
	movlw	0x72
	movwf	OSCCON
	btfss	OSCCON,IOFS
	bra		$-2
	movlw	0x0F
	movwf	ADCON1
	BSF		ProgBtnT, ProgBtn

	movlw	.4
	movwf	J_PACKET_COUNTER

#ifdef J_FLASH
	;Read a location in the last erasable row of flash program memory before the block that contains the configuration words
	;0xFF = Boot Mode, 0x00 = Run Mode
	movlw	J_FLASH_BOOT_MODE_L
	movwf	TBLPTRL

	movlw	J_FLASH_BOOT_MODE_H
	movwf	TBLPTRH
	
	movlw	J_FLASH_BOOT_MODE_U
	movwf	TBLPTRU	
	
	tblrd	*+			; Fill buffer
	incfsz	TABLAT,W
	bra	RVReset

#else
	btfss	ProgBtnP, ProgBtn
	bra	RVReset			; If not 0xFF then normal reset	
;	clrf	EECON1
;	setf	EEADR			; Point to last location
;	setf	EEADRH			
;	bsf	EECON1, RD		; Read the control code
;	incfsz	EEDATA, W
;	bra	RVReset			; If not 0xFF then normal reset
#endif

	bcf	TRISC, 6		; Setup tx pin
;	bsf	TRISC, 7		; Setup rx pin

	movlw	b'10010000'		; Setup rx and tx
	movwf	RCSTA1
	movlw	b'00100110'		
	movwf	TXSTA1

; *****************************************************************************




; *****************************************************************************
Autobaud
;
; ___	 __________            ________
;    \__/	   \__________/
;       |                     |
;       |-------- p ----------|
;
;	p = The number of instructions between the first and last
;           rising edge of the RS232 control sequence 0x0F. Other 
;	    possible control sequences are 0x01, 0x03, 0x07, 0x1F, 
; 	    0x3F, 0x7F.
;
;	SPBRG = (p / 32) - 1  	BRGH = 1

	bcf	RCSTA1, CREN		; Stop receiving

	movlw	b'00000011'		; x16 Prescale
	movwf	T0CON
	clrf	TMR0H			; Reset timer
	clrf	TMR0L
	
	rcall	WaitForRise
 
	bsf	T0CON, TMR0ON		; Start counting

	rcall	WaitForRise

	bcf	T0CON, TMR0ON		; Stop counting

	movff	TMR0L, ABTIME_L		; Read the timer
	
DivB32	rrcf	TMR0H, F		; divide by 2
	rrcf	ABTIME_L, F
	btfss	STATUS, C		; Rounding
	decf	ABTIME_L, F

	movff	ABTIME_L, SPBRG1	; Sync

	bsf	RCSTA1, CREN		; Start receiving

	movf	RCREG1, W		; Empty the buffer
	movf	RCREG1, W
		
; *****************************************************************************



; *****************************************************************************
; Read and parse the data.
StartOfLine

	rcall	RdRS232			; Get second <STX>
	xorlw	STX
	bnz	Autobaud		; Otherwise go back for another character

	lfsr	0, DATA_BUFF		; Point to the buffer

	clrf	CHKSUM			; Reset checksum		
	clrf	COUNTER			; Reset buffer count
		
GetNextDat				
	rcall	RdRS232			; Get the data
	xorlw	STX			; Check for a STX
	bz	StartOfLine		; Yes, start over	

NoSTX	movf	RXDATA, W
	xorlw	ETX			; Check for a ETX
	bz	CheckSum		; Yes, examine checksum		

NoETX	movf	RXDATA, W
	xorlw	DLE			; Check for a DLE
	bnz	NoDLE

	rcall	RdRS232			; Yes, Get the next byte
	
NoDLE	movf	RXDATA, W

	addwf	CHKSUM, F		; Get sum
	movwf	POSTINC0		; Store the data

	dcfsnz	COUNTER, F		; Limit buffer to 256 bytes
	bra	Autobaud

	bra	GetNextDat

CheckSum	
	movf	CHKSUM			; Checksum test
	bnz	Autobaud
; ***********************************************



; ***********************************************
; Pre-setup, common to all commands.
	movf	ADDRESS_L, W		; Set all possible pointers
	movwf	TBLPTRL
#ifdef	J_FLASH
#else
	movwf	EEADR
#endif
	movf	ADDRESS_H, W
	movwf	TBLPTRH
#ifdef	J_FLASH
#else
	movwf	EEADRH
#endif
	movff	ADDRESS_U, TBLPTRU

	lfsr	FSR0, PACKET_DATA

	movf	DATA_COUNT, W 		; Setup counter
	movwf	COUNTER
	btfsc	STATUS, Z
	reset				; Non valid count (Special Command)
; ***********************************************

 

; ***********************************************
; Test the command field and sub-command.
CheckCommand
	movf	COMMAND, W		; Test for a valid command			
	sublw	d'9'
	bnc	Autobaud

	clrf	PCLATH			; Setup for a calculated jump
	clrf	PCLATU
		
	rlncf	COMMAND, W		; Jump
	addwf	PCL, F
	
	bra	ReadVersion
	bra	ReadProgMem
	bra	WriteProgMem
	bra	EraseProgMem
	bra	ReadEE
	bra	WriteEE
	bra	ReadProgMem	;ReadConfig
	bra	WriteConfig
	bra	EOF
	bra RVReset
; ***********************************************



; ***********************************************
; Commands
; 
; In:	<STX><STX>[<0x00><0x02>]<0xFF><ETX>
; OUT:	<STX><STX>[<0x00><VERL><VERH>]<CHKSUM><ETX>
ReadVersion
	movlw	MINOR_VERSION
	movwf	DATA_BUFF + 2
	movlw	MAJOR_VERSION
	movwf	DATA_BUFF + 3

	movlw	0x04
	bra	WritePacket


; In:	<STX><STX>[<0x01><DLEN><ADDRL><ADDRH><ADDRU>]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x01><DLEN><ADDRL><ADDRH><ADDRU><DATA>...]<CHKSUM><ETX>
ReadProgMem
	tblrd	*+			; Fill buffer
	movff	TABLAT, POSTINC0

	decfsz	COUNTER, F		
	bra	ReadProgMem		; Not finished then repeat

	movf	DATA_COUNT, W		; Setup packet length
	addlw	0x05
				
	bra	WritePacket


; In:	<STX><STX>[<0x02><DLENBLOCK><ADDRL><ADDRH><ADDRU><DATA>...]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x02>]<CHKSUM><ETX>
WriteProgMem
#ifdef	SIXTY_FOUR_BYTE_WR 
	movlw	b'11111000'		; Force a boundry
	andwf	TBLPTRL, F

	movlw	.16

Lp1	movff	POSTINC0, TABLAT	; Load the holding registers

	pmwtpi				; Same as tblwt *+

	decfsz	WREG, F
	bra	Lp1

	decfsz	J_PACKET_COUNTER,F
	bra	SendAcknowledge

	tblrd	*-			; Point back into the block
#ifdef	J_FLASH
	movlw	b'00000100'	; Setup writes
#else
	movlw	b'10000100'	; Setup writes
#endif

	movwf	EECON1
	rcall	StartWrite	; Write the data

	tblrd	*+			; Point to the beginning of the next block
	
	movlw	.4
	movwf	J_PACKET_COUNTER

	bra	SendAcknowledge
#else
	movlw	b'11111000'		; Force a boundry
	andwf	TBLPTRL, F
 
	movlw	0x08

Lp1	movff	POSTINC0, TABLAT	; Load the holding registers

	pmwtpi				; Same as tblwt *+

	decfsz	WREG, F
	bra	Lp1
 
	tblrd	*-			; Point back into the block

	movlw	b'10000100'		; Setup writes
	movwf	EECON1
	rcall	StartWrite		; Write the data

	tblrd	*+			; Point to the beginning of the next block

	decfsz	COUNTER, F		
	bra	WriteProgMem		; Not finished then repeat

	bra	SendAcknowledge		; Send acknowledge
#endif

; In:	<STX><STX>[<0x03><DLENROW><ADDRL><ADDRH><ADDRL>]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x03>]<CHKSUM><ETX>
EraseProgMem
#ifdef	J_FLASH
	movlw	b'00010100'		; Setup writes
	movwf	EECON1

	rcall	StartWrite		; Erase the row

	movlw	0x4			; Point to next block
	addwfc	TBLPTRH, F
	clrf	WREG
	addwfc	TBLPTRU, F

	decfsz	COUNTER, F
	bra	EraseProgMem	

	bra	SendAcknowledge		; Send acknowledge
#else
	movlw	b'10010100'		; Setup writes
	movwf	EECON1

	rcall	StartWrite		; Erase the row

	movlw	0x40			; Point to next row
	addwf	TBLPTRL, F
	clrf	WREG
	addwfc	TBLPTRH, F
	addwfc	TBLPTRU, F

	decfsz	COUNTER, F
	bra	EraseProgMem	

	bra	SendAcknowledge		; Send acknowledge
#endif

; In:	<STX><STX>[<0x04><DLEN><ADDRL><ADDRH><0x00>]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x04><DLEN><ADDRL><ADDRH><0x00><DATA>...]<CHKSUM><ETX>
ReadEE
	clrf	EECON1 

	bsf	EECON1, RD		; Read the data
#ifdef J_FLASH
#else
	movff	EEDATA, POSTINC0
	infsnz	EEADR, F		; Adjust EEDATA pointer
	incf	EEADRH, F
#endif

	decfsz	COUNTER, F
	bra	ReadEE			; Not finished then repeat

	movf	DATA_COUNT, W		; Setup packet length
	addlw	0x05
				
	bra	WritePacket


; In:	<STX><STX>[<0x05><DLEN><ADDRL><ADDRH><0x00><DATA>...]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x05>]<CHKSUM><ETX>
WriteEE	
#ifdef	J_FLASH     
	 ;Need to take the device out of boot mode if this command is received and it is a J Flash device, 
     ;this writes 0's to a whole row in program memory since there is no actual Data EEPROM
	movlw	J_FLASH_BOOT_MODE_L
	movwf	TBLPTRL

	movlw	J_FLASH_BOOT_MODE_H
	movwf	TBLPTRH
	
	movlw	J_FLASH_BOOT_MODE_U
	movwf	TBLPTRU

	lfsr	FSR0, PACKET_DATA
	
	movlw	.64
	movwf	J_PACKET_COUNTER

	movlw	0
Loop
	movwf	POSTINC0
	decfsz	J_PACKET_COUNTER,F
	bra		Loop	

	lfsr	FSR0, PACKET_DATA

	movlw	b'11111000'		; Force a boundry
	andwf	TBLPTRL, F

	movlw	.64

Lp2	movff	POSTINC0, TABLAT	; Load the holding registers

	pmwtpi				; Same as tblwt *+

	decfsz	WREG, F
	bra	Lp2

	tblrd	*-			; Point back into the block

	movlw	b'00000100'	; Setup writes
	movwf	EECON1
	rcall	StartWrite	; Write the data

	tblrd	*+			; Point to the beginning of the next block
	
	movlw	.4
	movwf	J_PACKET_COUNTER

	bra	SendAcknowledge	

#else
	movff	POSTINC0, EEDATA

	movlw	b'00000100'		; Setup for EEData
	movwf	EECON1
	rcall	StartWrite		
	btfsc	EECON1, WR		; Write and wait
	bra	$ - 2

	infsnz	EEADR, F		; Adjust EEDATA pointer
	incf	EEADRH, F

	decfsz	COUNTER, F		
	bra	WriteEE			; Not finished then repeat
#endif
	bra	SendAcknowledge		; Send acknowledge
 

; In:	<STX><STX>[<0x06><DLEN><ADDRL><ADDRH><ADDRU>]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x06><DLEN><ADDRL><ADDRH><ADDRU><DATA>...]<CHKSUM><ETX>
;ReadConfig
;	movlw	b'11000000'
;	movwf	EECON1
;
;Lp5	tblrd	*+
;	movff	TABLAT, POSTINC0
;
;	decfsz	COUNTER, F
;	bra	Lp5			; Not finished then repeat
;
;	movf	DATA_COUNT, W		; Setup packet length
;	addlw	0x05
;
;	bra	WritePacket


; In:	<STX><STX>[<0x07><DLEN><ADDRL><ADDRH><ADDRU><DATA>...]<CHKSUM><ETX>
; OUT:	<STX><STX>[<0x07>]<CHKSUM><ETX>
WriteConfig
#ifdef	J_FLASH
	;If J Flash and this command is received do nothing
#else
	movlw	b'11000100'
	movwf	EECON1

	movff	POSTINC0, TABLAT	; Write to config area
	tblwt	*

	rcall	StartWrite

	tblrd	*+

	decfsz	COUNTER, F
	bra	WriteConfig		; Not finished then repeat
#endif
	
	bra	SendAcknowledge		; Send acknowledge
;************************************************

;************************************************
EOF:
#ifdef	SIXTY_FOUR_BYTE_WR 
	movlw	.16
	mulwf	J_PACKET_COUNTER
	movf	PRODL,W
	sublw	.64
	btfsc	STATUS,Z
	bra		SendAcknowledge
	
	movf	PRODL, W
	movwf	J_PACKET_COUNTER
	
	bcf		STATUS,C
	movlw	.16		;If there are more bytes to write in the row, we need to move the tblptr 
	addwf	TBLPTRL ;since the tblptr will be pointing at the last line of data in the hex file
	clrf	WREG
	addwfc	TBLPTRH
	addwfc	TBLPTRU
	

	movlw	0xFF	; Write 0xFF for remaining bytes of data in the row
Lp3	movwf	TABLAT	; Load the holding registers

	pmwtpi			; Same as tblwt *+

	decfsz	J_PACKET_COUNTER,F
	bra	Lp3
	
	tblrd	*-			; Point back into the block

#ifdef	J_FLASH
	movlw	b'00000100'	; Setup writes
#else
	movlw	b'10000100'	; Setup writes
#endif

	movwf	EECON1
	rcall	StartWrite	; Write the data

	tblrd	*+			; Point to the beginning of the next block
	
	movlw	.4
	movwf	J_PACKET_COUNTER

	bra SendAcknowledge
#else
	bra	SendAcknowledge
#endif



; ***********************************************
; Send the data buffer back.
;
; <STX><STX>[<DATA>...]<CHKSUM><ETX>

SendAcknowledge
	movlw	0x01			; Send acknowledge

WritePacket
	movwf	COUNTER

	movlw	STX			; Send start condition
	rcall	WrRS232
	rcall	WrRS232

	clrf	CHKSUM			; Reset checksum

	lfsr	FSR0, DATA_BUFF		; Setup pointer to buffer area	
	
SendNext				; Send DATA
	movf	POSTINC0, W
	addwf	CHKSUM
	rcall	WrData
	decfsz	COUNTER, F
	bra	SendNext

	negf	CHKSUM			; Send checksum
	movf	CHKSUM, W
	rcall	WrData

	movlw	ETX			; Send stop condition
	rcall	WrRS232

	bra	Autobaud
; *****************************************************************************

; *****************************************************************************
; Write a byte to the serial port.

WrData
	movwf	TXDATA			; Save the data
 
	xorlw	STX			; Check for a STX
	bz	WrDLE			; No, continue WrNext

	movf	TXDATA, W		
	xorlw	ETX			; Check for a ETX
	bz	WrDLE			; No, continue WrNext

	movf	TXDATA, W		
	xorlw	DLE			; Check for a DLE
	bnz	WrNext			; No, continue WrNext

WrDLE
	movlw	DLE			; Yes, send DLE first
	rcall	WrRS232

WrNext
	movf	TXDATA, W		; Then send STX

WrRS232
	clrwdt
	btfss	PIR1, TXIF		; Write only if TXREG is ready
	bra	$ - 2
	
	movwf	TXREG1			; Start sending

	return
; *****************************************************************************




; *****************************************************************************
RdRS232
	clrwdt

	btfsc	RCSTA1, OERR		; Reset on overun
	reset

	btfss	PIR1, RCIF		; Wait for data from RS232
	bra	$ - 2	

	movf	RCREG1, W		; Save the data
	movwf	RXDATA
 
	return
; *****************************************************************************





; *****************************************************************************
; Unlock and start the write or erase sequence.

StartWrite
	clrwdt

	movlw	0x55			; Unlock
	movwf	EECON2
	movlw	0xAA
	movwf	EECON2
	bsf	EECON1, WR		; Start the write
	nop

	return
; *****************************************************************************




; *****************************************************************************
	ORG	0x000A

WaitForRise
	btfsc	PORTC, 7		; Wait for a falling edge
	bra	WaitForRise
	clrwdt
WtSR	btfss	PORTC, 7		; Wait for starting edge
	bra	WtSR
	return
; *****************************************************************************




; *****************************************************************************
#ifdef	J_FLASH
	ORG	0x400
RVReset					

	ORG	0x408
RVIntH

	ORG	0x418
RVIntL

#else
	ORG	0x200
RVReset					

	ORG	0x208
RVIntH

	ORG	0x218
RVIntL
#endif
; *****************************************************************************


	END

EDIT: Now has a COMMAND #9 so it will return to NORMAL operation when called.
 
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