Re: A86: Rom Central - Database interactivity with rom calls
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Re: A86: Rom Central - Database interactivity with rom calls
'Jforcecmdnochar' is used to send the 86 back to the 'homescreen' context.
The stack is set back to the value that it was at when the system turns on.
It is a safe way to exit out of an asm program if you don't want to
get the stack backto it's proper value before 'ret'. It doesn't copy the
program
anywhere. If you want to save high scores then write it to a var. You can
create vars with illegal names so that they cannot be modified wothout an
asm program. Start your var name with a char < 'A'. Avoid @,#,$,!,^,? they are
used by the 86 for edit buffers.
Later
Pat
------------------
Original text
From: Jimmy =?iso-8859-1?Q?M=E5rdell?= <yarin@acc.umu.se>, on 2/24/98 3:28 AM:
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 M_rdell
IRC......: Yarin
Email....: mailto:yarin@acc.umu.se <-- NEW E-MAIL ADDRESS!!!!
Homepage.: http://www.algonet.se/~mja/
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