In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Coriolis wrote:

John, I think I see your problem. The instruction following snc is a compound statement (is compiled into multiple instructions), you cant follow a conditional skip with a compound instruction. Also there is some inefficiency in your code. Try the following:


[code]
(replace this text with your code) 


;Initialization code 

  mov   mptrlo, #tmsg & 255  ;seed memory pointer to begining of text 

  mov   mptrhi, #(tmsg >> 8)  

  

:DO   

  mov   m, mptrhi         ;move top 4 bits into the M register 

  mov   w, mptrlo         ;move bottom 8 bits into W
 

  IREAD                   ;reads the char and pos w+m into W
  mov   char, W           ;moves the char at w into char
  CJE   char,#0,@scroll   ;done with the top line, do the bottom line now
  call  @LCD_OUT
  INC   mptrlo            ;update memory pointer 

  SNC 

    INC mptrhi
  JMP   @:DO  

  

  

  

  

[/code]But I notice you are not using the top 4 bits stored at the memory location. When you only need 8 bits of data from the program memory area, don't use IREAD, use a jump table as such:


[code];define this so that the first instruction is in the first half of a memory page 
tmsg 

    jmp  pc+w 

    retw 'H' 

    retw 'e' 

    retw 'l' 

    retw 'l' 

    retw 'o' 

    retw  0 

  

  

;then in your code Initialization 

    mov idx, #1 

  

;then in your program body 

:DO 

    mov  w, idx        ;load index into w 

    call @tmsg         ;get idx'th character 

    mov  char, w       ;store character 

    jz   :endoftext    ;end of text 

    call @LCD_OUT
    inc  idx
    JMP   @:DO  

:endoftext 
[/code]
this method is much faster and can handle strings upto 254 characters.

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