Re: A86: Rom Central - Database interactivity with rom calls


[Prev][Next][Index][Thread]

Re: A86: Rom Central - Database interactivity with rom calls




At 18:30 1997-02-22 -0700, you wrote:
>
>why should we exit with this command?

I disassembled it a bit:

409C  C36305    jp    0563

0563  ED7BD6C1  ld    SP,(C1D6)
0567  0E00      ld    C,00
0569  C5        push  BC
056A  1805      jr    07         [0571]

0571  FDCB0CB6  res   6,(IY+0C)
0575  214109    ld    HL,0941
0578  CDC405    call  05C4

 05C4  - a long routines which changes many system variables

057B  97        sub   A
057C  C1        pop   BC
057D  C3A103    jp    03A1


It changes a lot of flags in IY-land, change systemvariables,
resets the stack (thus making is possible to quit the
program anywhere, without having to bother to reset the stack) etc.
If you press ON during the program, it won't BREAK. It clears
the keyboard buffert. It saves a lot of code.

Also, it MIGHT copy the program back to the page 2-7, thus
saving hiscore and similiar. Or some other calc MUST do that.
Pat? :-)

--
Real name: Jimmy Mårdell                 
IRC......: Yarin                         
Email....: mailto:yarin@acc.umu.se      <-- NEW E-MAIL ADDRESS!!!!
Homepage.: http://www.algonet.se/~mja/


Follow-Ups: References: