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PC to DPTR ?

Gopivishwanath S

Hi,


How to move the program counter(PC) to DPTR.Can any one suggest on this.

Thanks in advance,

Regards,
Gopi

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  • 0 in reply to Andy Neil

    What? You are wrong here..

    MOVC A,@A+DPTR
    reads byte from program memory exactly same as it does command 
    MOVC A,@A+PC
    and exactly the same as hardware fetches the command byte.
    Hardware does not do different timings/read cycles for reading both command and data bytes from program memory. When you use command MOVC A,@A+DPTR then core works like it reads just byte of command.
    So I cannot understand what do you talk about that DPTR=0x1234 may well address a different physical address location from PC=0x1234. If you use MOVC command then there is no difference. Ofcoz, if you will use MOVX... command then it will be a big difference (no PSEN signal etc).

    Good days!

Reply
  • 0 in reply to Andy Neil

    What? You are wrong here..

    MOVC A,@A+DPTR
    reads byte from program memory exactly same as it does command 
    MOVC A,@A+PC
    and exactly the same as hardware fetches the command byte.
    Hardware does not do different timings/read cycles for reading both command and data bytes from program memory. When you use command MOVC A,@A+DPTR then core works like it reads just byte of command.
    So I cannot understand what do you talk about that DPTR=0x1234 may well address a different physical address location from PC=0x1234. If you use MOVC command then there is no difference. Ofcoz, if you will use MOVX... command then it will be a big difference (no PSEN signal etc).

    Good days!

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