I did some similar fooling around by populating an SRAM card with
battery-backed rams. It wasn't worth it at the time, though.
I even have a 32K card with battery backup on board. I also built a RAMDISK
with a battery backup so I could dump an entire SA1004 to it in one stroke
and keep it alive with a couple of motorcycle-battery sized gel cells and a
major DC-DC converter. I built one for a business partner and hooked up
solar cells and one of those adjustable DC-DC converters (one of the old,
Old, OLD Boschert adjustable open-frame types) to bring the 60 Vdc or so
down to 14Volts and another to build the 5 Volts from that.
Dick
-----Original Message-----
From: Allison J Parent <allisonp_at_world.std.com>
To: Discussion re-collecting of classic computers
<classiccmp_at_u.washington.edu>
Date: Tuesday, November 02, 1999 6:48 PM
Subject: Re: Northstar Horizon
><Nowadays, it's really tempting to use an EPROM or Battery-Backed SRAM to
><hold the entire CP/M CCP, BDOS, and BIOS, and let the warm boot reload the
><CCP from there. That would certainly make the control-c quicker.
>
>Nowadays! I did this back in early 81 using 2732s. I put a monitor, bios,
>ZCPR2 and BDOS in that. The CCP and BDOS only eats 5.5k. It was set up
>rather odd as the system runs from a small 2716 at cold boot with a monitor
>and then by user command loads the 8k image into ram from IO addressed
>"romdisk". The CTRL-C was very fast as it could do INIR copies from the
>rom. A later version still running is 256k of eprom (27512s) had all of
>cpm, loader, ASM, VEDIT, SID (and more). This version the boot EEprom
>is at 0000 and is truncated bdos, bios and a loader. This was done so that
>I could have it load CPM.SYS image for testing from the selected drive
>including the ROMDISK. This is raw speed.
>
>Allison
>
>
Received on Wed Nov 03 1999 - 00:29:40 GMT