A86: RST 10
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A86: RST 10
Alan Bailey wrote:
> At 04:13 PM 9/23/97 -0400, you wrote:
> >In a message dated 97-09-23 15:19:40 EDT, you write:
> >
> >>
> >> can someone tell me how to use RST commands and what exactly they're used
> >> for? sorry this is proably basic stuff to ya'll. all i know about them is
> >> that they're used to find things in memory right?
> >>
> >> thanx,
> >> Patrick
> >>
> >>
> >
> >Restarts are used to call locations in ROM that are called commonly. RST 20h
> >and RST 10h both deal with finding variables. I believe 00h has something to
> >do with formatting the calc, or maybe a self test. Anyway, they go all the
> >way from 00h to 40h in increments of 8h. (00h,08h,10h,18h, etc). I think
> >they actually call that address in rom but are faster or more efficient or
> >something. (someone correct me if I'm wrong) Once I get my Z80 books (if
> >_ever_) then I can tell you more about it... :-(
> >
> >~Stephen Hicks
> >
> >
>
> Yeah, you're exactly right. TI just put commonly used routines at those
> entry points. The reason is because <rst 10h> is 2 bytes shorter than
> <call $0010> and those bytes can add up.
>
> RST $10 finds the variable whose id, length, and name are in op1
> RST $20 puts the variable id, length, and name into op1
>
> RST $00 does start the calc, because that is the initial code started when
> calc is started. (actually only when batteries are taken out and back in)
>
> Alan Bailey mailto:bailela@charlie.cns.iit.edu
Thanx for the info u've given me so far. Does ne one have a source example of
the RST command?
thanx again
Patrik
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