
Matthew blogged about his
Amiga CDTV
project, a truly
unique Amiga hack which also manages to be a
novel
Doom project (no mean feat: it's a crowded space)
This re-awakened my dormant wish to muck around with my
childhood
Amiga some more. When I
last wrote about
it (four years ago ) I'd upgraded the disk drive emulator
with an OLED display and rotary encoder.
I'd forgotten to mention I'd also sourced a modern trapdoor RAM expansion which
adds 2MiB of RAM. The Amiga can only see 1.5MiB
1 of it at the moment, I
need perform a
mainboard modification to access the final 512kiB2, which
means some soldering.
What I had planned to do back then: replace the switch in the left button of the
original mouse, which was misbehaving; perform the aformentioned mainboard mod;
upgrade the floppy emulator wiring to a ribbon cable with plug-and-socket, for
easier removal;
fit an RTC chip to the RAM expansion board to get clock support in the OS.
However much of that might be might be moot, because of two
other mods I am considering,
PiStorm
I've re-considered the
PiStorm accelerator mentioned in Matt's blog.
Four years ago, I'd passed over it, because it required you to run Linux on a
Raspberry Pi, and then an m68k emulator as a user-space process under Linux. I
didn't want to administer another Linux system, and I'm generally uncomfortable
about using a regular Linux distribution on SD storage over the long term.
However in the intervening years
Emu68,
a bare-metal m68k emulator has risen to prominence. You boot the Pi straight
into Emu68 without Linux in the middle. For some reason that's a lot more
compelling to me.
The PiStorm enormously expands the RAM visible to the Amiga. There would be
no point in doing the mainboard mod to add 512k (and I don't know how that
would interact with the PiStorm). It also can provide virtual
hard disk devices to the Amiga (backed by files on the SD card), meaning the
floppy emulator would be superfluous.
Denise Mainboard
I've just learned about a truly incredible project:
the Denise Mini-ITX Amiga
mainboard. It fitss into a Mini-ITX
case (I have a suitable one spare already). Some assembly required. You move
the chips from the original Amiga over to the Denise mainboard. It's compatible
with the PiStorm (or vice-versa). It supports PC-style PS/2 keyboards (I have a
Model M in the loft,
thanks again Simon) and has
a bunch of other modern conveniences: onboard RTC; mini-ITX power (I'll need
something like a
picoPSU too)
It wouldn't support my trapdoor RAM card but it takes a 72-pin DIMM which can
supply 2MiB of Chip RAM, and the PiStorm can do the rest (they're compatible
3).
No stock at the moment but if I could get my hands on this, I could build
something that could permanently live on my desk.