transfer a string from ROM to an array

[Marcick]

Richard,
Thanks for your time but .. if you have some more ... could you please take my sample above and correct it so it works ?
It's two days I'm turning crazy.
Anyway thank you
Marco

[richard]

'pic18f45k20
'****************************************************************
'*  Name    : UNTITLED.BAS                                      *
'*  Author  : [select VIEW...EDITOR OPTIONS]                    *
'*  Notice  : Copyright (c) 2015 [select VIEW...EDITOR OPTIONS] *
'*          : All Rights Reserved                               *
'*  Date    : 4/14/2015                                         *
'*  Version : 1.0                                               *
'*  Notes   :                                                   *
'*          :                                                   *
'****************************************************************
'*  Name    : UNTITLED.BAS                                      *
'*  Author  : [select VIEW...EDITOR OPTIONS]                    *
'*  Notice  : Copyright (c) 2015 [select VIEW...EDITOR OPTIONS] *
'*          : All Rights Reserved                               *
'*  Date    : 4/14/2015                                         *
'*  Version : 1.0                                               *
'*  Notes   :                                                   *
'*          :                                                   *
'****************************************************************
 #CONFIG
  CONFIG  FOSC = INTIO67
  CONFIG  FCMEN = OFF
  CONFIG  IESO = OFF
  CONFIG  PWRT = OFF
  CONFIG  BOREN = SBORDIS
  CONFIG  BORV = 18
  CONFIG  WDTEN = ON
  CONFIG  WDTPS = 512
  CONFIG  CCP2MX = PORTC
  CONFIG  PBADEN = OFF
  CONFIG  LPT1OSC = OFF
  CONFIG  HFOFST = ON
  CONFIG  MCLRE = ON
  CONFIG  STVREN = ON
  CONFIG  LVP = OFF
  CONFIG  XINST = OFF
  CONFIG  DEBUG = OFF
  CONFIG  CP0 = OFF
  CONFIG  CP1 = OFF
  CONFIG  CP2 = OFF
  CONFIG  CP3 = OFF
  CONFIG  CPB = OFF
  CONFIG  CPD = OFF
  CONFIG  WRT0 = OFF
  CONFIG  WRT1 = OFF
  CONFIG  WRT2 = OFF
  CONFIG  WRT3 = OFF
  CONFIG  WRTC = OFF
  CONFIG  WRTB = OFF
  CONFIG  WRTD = OFF
  CONFIG  EBTR0 = OFF
  CONFIG  EBTR1 = OFF
  CONFIG  EBTR2 = OFF
  CONFIG  EBTR3 = OFF
  CONFIG  EBTRB = OFF
#ENDCONFIG


  define OSC 64
 osccon=$70   '64 mhz
 OSCTUNE.6=1
 
 
 
 pause 2000
 
Serout2 PORTb.7,84,["ready",13,10] 
 
Addr var word
 Char var byte
 cnt var byte
inbuff  var byte[30]
buff var byte[30]
 Clear

 



 goto StartLoop ' Required

 String1:
 @ da "This is a string",0

 AnotherString:
 @ da "Here is another string",0

 '------------GetAddress Macro - Location insensitive -------------------------
 ASM
GetAddress macro Label, Wout ; Returns the Address of a Label as a Word
   CHK?RP Wout
   movlw low Label
   movwf Wout
   movlw High Label
   movwf Wout + 1
   endm
 ENDASM


 StartLoop: ' This loop repeats continuously just as a test.
@ GetAddress _String1, _Addr ' Get address of String
 cnt=0
 gosub StringOut ' Send the String
 Serout2 PORTb.7,84, [13,10] ' New Line
 Serout2 PORTb.7,84, ["inbuff ",str inbuff\cnt ,13,10] ' New Line


@ GetAddress _AnotherString, _Addr ' Get address of String
 cnt=0
 gosub StringOut ' Send the String
 Serout2 PORTb.7,84,[13,10] ' New Line
 Serout2 PORTb.7,84, ["inbuff ",str inbuff\cnt ,13,10] ' New Line
 pause 500
 goto StartLoop ' Repeat


 StringOut: ' Send the string out via Hserout
 Readcode Addr, Char ' Get a character
 if Char = 0 then StringDone ' Look for Null char, Stop if found
 buff[cnt]=char
 cnt=cnt+1
 Serout2 PORTb.7,84, [Char] ' Send char
 Addr = Addr + 1 ' Point to next character
 goto StringOut ' Continue with rest of the string
 StringDone:
 ARRAYWRITE inbuff,cnt,,[str buff]
 return


 end

I do it this way , and use the bounds checking features of arraywrite

[Marcick]

Well, any help is appreciated, so thank you anyway, but this is not what I'm asking.
My intent is not to use Arraywrite because consumes a lot of space.
With this sample code that now works I transfer a ROM string to an array, but I want also the destination array to be a parameter passed to the macro.
So with a single macro I could transfer to inbuff or testbuff or any buffer Is declared.

	Define 		USE_LFSR 	1
	DEFINE		OSC			8
	DEFINE		DEBUG_REG	PORTB
	DEFINE		DEBUG_BIT	4
	DEFINE		DEBUG_BAUD	9600
	DEFINE		DEBUG_MODE	0	
	
	OSCCON		=%01110000	

	inbuff		VAR BYTE[100]
	x			VAR BYTE
	y			VAR BYTE
	LS0 		VAR WORD
	LS1			VAR WORD
	goto Lp1

ASM
LoadInbuff	 macro Text
	CHK?RP _LS0
 	movlw low Text		; here I load in LS0 the ROM address of the source string
	movwf _LS0
 	movlw High Text
 	movwf _LS0 + 1
	L?CALL   _Lstr
 endm
ENDASM

Lstr:
	y=0
  	do
	    	peekcode LS0, x
		inbuff(y)=x
		if x=0 then exit
		y=y+1
		LS0=LS0+2
	loop
	return


Lp1:
	@ LoadInbuff _ROM_CfgString
	debug str inbuff\100,13,10
	goto lp1


ROM_CfgString:       PokeCode "This a test string",0

[richard]

I understand but pbp does not allow pointers like in C . the only way I can see for this to be done is to have either a user cmd or asm code that actually mimics arraywrite's array loading method anyway .I'm sure something like that could be made accept a pointer to the array to be loaded .
I'm just having trouble seeing any point to this. my prog with arraywite 1041 bytes , with arraywrite commented out 951 bytes ,surely 90 bytes is pretty good I'm sure my asm attempts would be much worse than that
I have to ask why do this at all . I can't see a good reason to read a string from flash into ram ,surely its best shuffled off to its destination directly . if it needs to be altered before its used was it really a good move putting it in flash memory in the first place.
have a look at this thread post#50 where I update portions of an array with EXT modifiers and arraywrite . the fixed unchanging parts could be in flash
http://www.picbasic.co.uk/forum/showthread.php?t=19420
perhaps if you provide a little more detail .....

[Marcick]

Hi Richard,
yes, strings need to be altered before use.
Well, I had about 3K free on 64k (PIC18F4680) and needed to add more code, so I was looking for some tricks to save space and make a diet to the actual code.
I have noted that if I substitute an arraywrite entry (for a string of about 100 char) with the method above, I save around 600 bytes of code. I have about 10 difefrent strings, so the total saved space is several KB.
To be honest I can't understand why there is so much difference between the two methods ....
Also I have noted this: in a blank project like the sample above, the difference between the two methods is about 150 bytes. Inside my 63KB project, the difference is more than 600 bytes.
So it probably depends where the instruction and the buffer are located (bank switching, etc). For thei sreason I wonder also if the method above with the macro is correct or can bring to unexpected behavours in some situations .....
For example: why did you say before "interrupts need to be disabled" ? Context is fully saved and restored in the interrupt routines. Also I use "PBP Instant Interrupt" of that great Darrel that should be bullet-proof.
Marco

[richard]

why did you say before "interrupts need to be disabled

I was thinking that if were to read the flash using TABLPU reg and index through the ram array using fsr0 then I'm not convinced that method is interrupt proof
but your not doing that anyway


I expect you realise that pokecode uses twice the memory to store a string compared to da

[Marcick]

well, I was not understanding why I had to increment the pointer by two when reading data ...
I have subsituted now pokecode with da and peekcode with readcode and saved another kb .. thanks !
Marco