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???
04/14/04 21:53
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#68499 - RE: STARTUP.A51
Responding to: ???'s previous message
The flaw in the code is that it clears R0 as the last thing. R0 then gets decremented to FF and the whole loop starts over. But this time the loop starts at address FFh, which is the stack area. Crash!
Why? Because the R0 register is located at memory address 00h, R1 at 01h, etc.

The registers on the 51 series CPU's exist at the lower addresses in RAM. Read up on register banks and the memory architecture.
Change your code to
MOV R0, #IDATALEN-2 and try it again.
Rgs,
Steve

List of 22 messages in thread
TopicAuthorDate
Assembly works but C...            01/01/70 00:00      
   RE: Assembly works but C...            01/01/70 00:00      
      RE: Assembly works but C...            01/01/70 00:00      
         RE: Assembly works but C...            01/01/70 00:00      
            RE: Assembly works but C...            01/01/70 00:00      
               RE: Assembly works but C...            01/01/70 00:00      
   RE: Assembly works but C...            01/01/70 00:00      
      RE: Assembly works but C...            01/01/70 00:00      
         STARTUP.A51            01/01/70 00:00      
            RE: STARTUP.A51            01/01/70 00:00      
               RE: STARTUP.A51            01/01/70 00:00      
                  Stand Still...            01/01/70 00:00      
                     RE: Stand Still...            01/01/70 00:00      
                  RE: STARTUP.A51            01/01/70 00:00      
               RE: STARTUP.A51            01/01/70 00:00      
         function for LCD in C...            01/01/70 00:00      
            RE: function for LCD in C...            01/01/70 00:00      
      RE: Assembly works but C...            01/01/70 00:00      
         RE: Assembly works but C...            01/01/70 00:00      
            RE: Assembly works but C...            01/01/70 00:00      
               RE: Assembly works but C...            01/01/70 00:00      
            RE: Assembly works but C...            01/01/70 00:00      

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