Storing data to program memory with MPASM

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kemalkemal

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Hi
this is my demo code in order to see whats going on when i use directives like dw or da.
Code: 
	list		p=16f877A	
	#include	<p16f877A.inc>	
		__CONFIG _CP_OFF & _WDT_OFF & _BODEN_OFF & _PWRTE_ON & _XT_OSC & _WRT_OFF & _LVP_OFF & _CPD_OFF
	ORG     0x000           
	nop			 
  	goto    main            
	ORG     0x004            
  	retfie                  
main
string1	dw	"xxddd",0
string2	da	"ddfsfdg"
movlw	b'01000110'
goto	main
	END
when i animate it, as shown in the picture below, PCL is loaded with 0x05 normally ,

then one step later it is loaded with 0x4A and going somewhere else skipping string2 line.

why is that ?
(My final aim is to load some string into the program memory and then call them later in order to send an LCD.)
 

When I delete the
Code: 
string1	dw	"xxddd",0
line everything became fine. I am able to store packed Ascii codes of "ddfsfdg" into the program memory. But what is the point to store data into the program memory if I have no way to extract that data. By manipulating PCL i can reach to the related portion of program memory but a tool to extract data is not to my knowledge. Is there a way to do it for 16F877A? Thanks
 

Thanks to edaboard community i think i found the solution. key word is IDASM16.ASM which a source file that stays in your MPASM file. You must use this with a relocatable code. If i should brief it there is "init_entry_to_addr" variable in IDASM16 which shows you the data memory address of your idata string. Of course if your idata string is composed of 3 characters than IDASM16 increases init_entry_to_addr one by one each time it stores your variable into the data memory. If you want to use your variable may be you can put a call to your subroutine in IDASM16.
(IDASM16 code section)
Code: 
	bsf     STATUS, IRP               ;set the IRP bit.
	movwf   INDF
[COLOR="#FF0000"][B];;;;---->>>call subroutine from here[/B][/COLOR]
;  After copying one entry we need to:
;    1. Increment the program memory (source) address
;    2. Increment the data memory (destination) address
;    3. Decrement the init_entry_size

        BANKSEL init_entry_from_addr

(PS:I dont guarantee that my writings are completely right.)
 

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