Date : Sun, 29 Oct 2006 15:42:58 +0100
From : s-whs@... (W.Scholten)
Subject: Replay for 1770/8271, same hardware?
L.S.
I've been emailing with Michael in the UK regarding the replay system.
Basically, the problem is that he would like a replay for 8271, but now
has a replay for old 1770 systems (1770 replay ROM 1.01, meant according
to the ads for DDOS 3.46 and Soli DDFS issue 1).
I suspect that all replay hardware is the same and that are a few
different ROM versions, so changing the ROM (with a little soldering)
should then solve this problem (except his soldering skills may not be
that great, but see below). Is this correct? Has anyone tried to change
the replay ROM?
I know of the following replay systems:
- 8271 (ROM 1.00 & 1.10)
- 1770, old interfaces from Opus & Solidisk (1770 ROM 1.01)
- 1770 Opus Challenger (ROM version?)
- 1770 all interfaces/DFS ROMs, i.e. including the Acorn compatible
ones (Watford Mk2, Soli iss.2). (1770 ROM 1.17)
- Then there's some information on replay data sheet 18 Michael found:
Replay data sheet 18, from November 1988
=====================================================================================
Users of 1770 disk interfaces will be interested to learn that REPLAY
Mk2 is now available. This new version has the same hardware as the Mkl,
but the software is based on the Master REPLAY program. Extra features
include:
More effective tape to disk transfer.
Built-in formatting and verification of disks.
Automatic file creation - for saving to REPLAY disks at any time.
Double density 18 sector operation, with up to 22 files per disk.
Sound on/off and screen positioning features.
The new version will suit _any 1770_ disk interface. Conversion from Mkl
to Mk2 will involve replacing the 8k ROM with a 16k ROM and a new User
Guide is necessary. Mkl disks will not run on the Mk2 REPLAY. Please
'phone for a price and further details. _NB. 1770 interfaces only.
_=====================================================================================
This of course says that the early and late 1770 replay units are
identical except for the ROM. So my hunch about the hardware being the
same for all including the 8271 might be right :) But is it?
The replay ROMs in the ROM archive are:
REPLAY__8271__1.00
REPLAY__8271__1.00_alt1
REPLAY__1770__1.01
REPLAY__1770__1.17
Is the REPLAY__1770__1.17 the Mk2 ROM? It is 8k though. Maybe they
could squeeze it into 8k after all?
If replacing a ROM would work, I can send Michael an EPROM programmed
with the 8271 replay. If that wouldn't work, does anyone have a 8271
replay unit he might like to swap or sell to him? (perhaps preferable
considering the soldering to be done). Email me if you're interested and
I'll send you his email address.
Btw, has anyone scanned those replay data sheets and made available for
downloading?
Regards,
Wouter
--
BBC micro | Calculators | Classic PC games: http://www.xs4all.nl/~swhs/whs/