Re: Laser 128 Questions

["ict@ccess" <gids.rs@sasktel.net>]

On May 23, 4:09 pm, Steven Hirsch <snhir...@gmail.com> wrote:
> Has anyone ever disassembled the ROM on one of these?  I'm finding that the
> firmware for the external disk port (Slot 7) does not recognize or work with
> intelligent SmartPort devices (e.g. SPVHD or Unidisk 3.5).
>
> This is the same behavior as the newer VTech (Central Point) disk controller
> cards.  There, I have had success with retrofitting an older image to get
> Unidisk support.
>
> I have a feeling I can overlay this into the Laser system ROM, since they use
> the same ASIC chip as drive controller.  I'm not sure how they map the single
> EPROM to cover the standard system ROM and slot ROM / C800 expansion for the
> various slots.  Can probably figure this out by lots of disassembly and a bit
> of luck, but thought I'd ask if anyone had already done so.
>
> I find it rather odd that the Laser cannot handle intelligent drives, while
> the earlier Apple //c can.
>
> Steve

Yes, I had disassembled quite a bit of the slot roms.  A lot of the
motherboard ROM regularly entered the slot 3 ROM for 80 column work,
since not all of the code could fit in where the cassette routines
were.  The slot 1 and 2 ROMS had a few entry points that dealt with
serial devices.  If you were to hold down ctrl-P on startup, you would
enter the serial device control panel.  At least that worked on the
128EX and 128 EX/2.  Not sure about the original 128.

The monitor disassembly code also entered either the slot 4 or slot 6
ROM (too long ago to remember)  to get the mnemonics to display the
actual disassembly.  Laser had no compression schemes in its
motherboard ROM, as to not infringe on Apples ROMs.  Everything was
spelled out fully.

I had read somewhere when I first purchased my Laser that neither the
5.25 or the 3.5 drives worked on a real apple.  So I never tried
plugging them in for fear of frying the motherboard or the drives.
But I assume it was another one of those attempts by Laser to be
different than Apple and the code for the Smartport might have been
too compact or too confusing to try and rewrite it another way as to
not infringe on Apples code

Rob