🚀 go-pugleaf

In article <892@boink.UUCP> harald@boink.UUCP (Harald Milne) writes:
>In article <13839@cbmvax.commodore.com>, daveh@cbmvax.commodore.com (Dave Haynie) writes:

>    At this point, fully believing the ROMs would go poof, I rebooted to snoop
>around with the Manx db debugger. Just for the hell of it, I looked at the
>same address, and lo, the ROMs were still in the Amiga's address space!

>	What Im leading up to Dave, is I still believe you, and therefore would like
>to know if I have a different A2620 than perhaps what is the production A2620.

Probably not.  The only issue here is ROM revision.  There was at least one
A2620-only release.  Some time after that, there were several releases that
added A2630 knowledge and fixed a few bugs.  The A2630 I have here, which is
very likely using A2620-vintage ROMs, also shows $00f8xxxx within AmigaOS.

>	Really curious now, I looked at what controlled the ROM access. On sheet
>1 of the schematics in the A2620 manual, there is _CSROM (with an interesting
>? by the label). On sheet 3, _CSROM appears to be generated by the PAL U304.

>	I guess I must have a really old set of PALs. Perhaps preproduction?

Well, CSROM* is certainly the PAL that creates that chip select.  But it's the
first configuration register that controls which memory ranges the ROM will
be selected for.  This register is set up by the A26x0 ROMs before AmigaOS is
invoked.  The ROMs can be left at $0000xxxx, $00F8xxxx, or neither of these.

>I remember hearing about a change for the GVP disk controller after the A2620
>was initially released, 

Again, that was a bug in the ROM code.  The A2620 ROMs code for autoconfig was
confused about 128K devices.  This was never an issue in normal operation,
but could be seen when booting into the menu/monitor.  There has only been one
set of PALs for the A2620 (all 12 of them...).

>	I kind of like, and don't mind the ROMs being there. That is unless it
>may become a problem in the future.

If the $00F8xxxx overlay is a problem with 2.0, you will want a ROM set that
fixed that.  Other than for that, however, you're not likely to need a change.

>Harald Milne                   RISCy business	       uunet!ccicpg!boink!harald


-- 
Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
      Get that coffee outta my face, put a Margarita in its place!