reviving this thread.  Great info on a hidey hole usable when NOT in TEXT.
..Steve


On Thu, May 31, 2018 at 4:38 PM Ken Pettit <[email protected]> wrote:

> Oh,
>
> And speaking of hidey holes, there is a 52-byte hidey hole that exists
> while BASIC is running that I don't believe anyone has ever realized
> exists or has used before.  On the M100 this address starts at F6EBH.
> It is a table of 26 2-byte addresses which is used only in TEXT mode.
> TEXT initializes and maintains this table to hold the starting address
> of the text within the .DO file being for each line on the LCD (or DVI
> ... thus 26 entries).  I call it the "line starts array".  TEXT uses it
> when updating the display to keep track of the location in the .DO file
> to start drawing from ... that way it doesn't have to calculate from the
> beginning of the file for each display update.
>
> But in BASIC mode, these 52 RAMs of ram are unused.  Enjoy!
>
> Ken
>
> On 5/31/18 12:49 PM, Ken Pettit wrote:
> > Yeah, that's just 4 bytes of code.  That could go in a hidey hole
> > (Suzuki, Hayashi, etc.).
> >
> > Ken
> >
> > On 5/31/18 12:45 PM, John Gardner wrote:
> >> ...Reljmp.pdf...
> >>
> >> Nice.  Thanks.
> >>
> >> On 5/31/18, John Gardner <[email protected]> wrote:
> >>> Hi John -
> >>>
> >>> I'm thinking about Ken's idea of having code embedded in BASIC
> >>>
> >>> jumping to code embedded in a DO file -  Sounds workable, even
> >>>
> >>> reasonable with a big routine,  or a number of smaller routines.
> >>>
> >>> On 5/31/18, John R. Hogerhuis <[email protected]> wrote:
> >>>> On Thu, May 31, 2018 at 12:15 PM, John Gardner <[email protected]>
> >>>> wrote:
> >>>>
> >>>>> Your code can figure out it's execution address  with something like:
> >>>>>
> >>>>>           call      @Boo
> >>>>> Boo   pop     B
> >>>>>           pop     A
> >>>>>
> >>>>> Boo's address is now in register pair A,B...
> >>>>>
> >>>> But you kind of already know since that code would have to be
> >>>> relocated
> >>>> to
> >>>> function.
> >>>>
> >>>> -- John.
> >>>>
> >
>
>

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