| Z88 SOFTWARE
& HARDWARE SUPPORT
AND PRICE LIST
a Cambridge Z88 Palmtop Computer.
following comments were made by Frank Davis @ FWD
THE VERSION 4 ROM FOR THE
John Rish of Home Electronics is now
able to install internal RAM and the V4 ROM in the Z88.
The internal RAM can be increased to either 128K or 512K,
as opposed to the 32K that the Z88 came with internally.
You may do this (if you feel qualified and are willing to
take the risk upon yourself of opening and modifying your
Z88). You can email him at: firstname.lastname@example.org
Your Z88 may be sent to John for the modifications to be
done, or for any needed repairs. Just email for where to
send it to. Basic cost for repair is $40 plus parts as
needed. John Rish is an excellent and qualified repair
technician for your Z88 and we highly recommend and trust
him. Please allow 8-12 days for turnaround on repairs,
though often it may be faster than that. John is also
available for other Cambridge or Sinclair Computer
repairs as well as monitors.
THE V4 ROM CONTAINS THE FOLLOWING FIXES:
LOST HANDLES :
V3, handles could be lost by pre-empting the Filer during
a catalogue, resulting in a "File in use" error
which required a soft reset to clear. ROM CARDS
It is no longer possible to insert and remove cards while
the Z88 is switched off, which previously could cause the
Z88 confusion. Now the Z88 wakes up when the flap for
card intallation/removal is opened.
updating the PrinterED settings under V3, it is common to
encounter a "FAIL" condition. This has been
fixed with V4. In addition, the "Allow line
feeds" option now works correctly.
system no longer gets confused if files are present in
this useful device if the Z88 is reset.
Z88 will now behave as an expanded machine (giving a full
map in PipeDream, and 40K workspace in BASIC) if there is
128k RAM anywhere in the system, and not just in slot 1
as it did with V3 ROM.
In V3, a problem sometimes occurs with Filer when marking
a file after scrolling the cursor. This caused the first
letter of the filename to disapear, but has been fixed
These are some of the improvements you can expect to have
if you have your Z88 upgraded from the V2.2 or the V3
ROMs to the V4 ROM. Email us for further details.
The bad side of the new Version 4 ROM is that in order to
make room for all these changes they had to remove most
of the online help files built-in to the V3.0 ROM. There
was only so much room.
Internal Z88 Memory Expansion
Many thanks go out to Don Walterman, a long time friend,
for these instructions telling you how to upgrade your
Z88's internal RAM to 128K or 512K. This is not to be
done by the faint hearted or the beginner at
"I've always wanted to add more internal memory to
the Z88 (they can already easily have external memory
added). I got started with the Z88 a bit late in it's
life, so a lot of the products I read about were no
longer available. reading back through old magazines, I
noticed some advertisements for internal memory expansion
kits. since none of them are availble any more (except
from Home Electronics Service in the USA and from Wm.
Richardson in the UK just recently) I decided to make a
"I started with the Z88 service manual. It explains
that the internal memory is pseudo-static memory. This
type is not common. I did manage to find one
advertisement for it. The company is Microprocessors
Unlimited in the USA - telephone (918) 267-4961. They
stock both 128K and 512K pseudo-static memory that's
perfect for the Z88 (80ns or 100ns will work fine)."
128K pseudo-static RAM: Hitachi HM658128ALP @ $10.95
512K pseudo-static RAM: Hitachi HM658512LP @ $29-$33
(these prices are subject to change as are all memory is
for computers, and have been up and down lately)
"Back to the service manual - it also explains that
the memory socket is pinned for the 128K memory chip. The
only problem is that every Z88 board I've looked at has
the memory chip soldered in. Some of you may be lucky
enough to have a socketed chip, but don't expect it.
Carefully unsolder the old memory chip and install a low
profile socket. Make sure to use a 32 pin socket. You
will need to clean out the extra four holes above the 32K
RAM, which only uses 28 pins." NOTE: a solder sucker
or desoldering iron will come in handy here.
"I tried the 128K chip first, and it worked right
away. The Z88 recognised it without doing anything
special. I installed the 512K chip and it only saw the
first 128K. Back to the service manual."
"The service manual explains that the Z88 is
designed to access four blocks of one megabyte each. To
access the full one megabyte, you need to use all the
memory address lines. Memory address lines 17 and 18
don't go to the internal RAM socket. They do go to each
of the option card connectors. It happens that there are
three pads by each connector. Use the two pads next to
each other that go to second and the third pin from the
end of the connector. These pads are memory address lines
17 and 18. They are perfect for this project. Solder a
wire to each pad on the foil side of the board. make sure
your wire doesn't go through the pad too far. There is a
metal bar that too long a wire could short against."
"There are a number of feed-through holes on each
side of the internal RAM chip. I prefer the feed-through
hole by pin 3 of the memory chip and the feed-through by
pin 18 of the memory chip. This allows you to run the
wire right to the pins you want. Don't solder the wire to
the feed-through holes. Just run the insulated wire
through it. Feed one of the wires through each feed hole.
don't use too much wire - you want to make sure none of
the wires interferes with the option slots. I left pins 1
and 30 bent out of the socket so that It would be easy to
solder the extra memory lines onto the pins."
"After attaching the two memory lines, the Z88 woke
up with 512K. It recognised all of it with no problems -
despite reports that a V4 ROM is required for the 512K
internal memory." EDITOR's NOTE: It does recognize
all of the memory without the V4 ROM, but both ROMs treat
the memory different. You will get much better use of
your full memory with the V4 ROM.
One of the things John Rish tries is to keep the Z88 a
viable palmtop computer that is fun and easy, while
useful, and within most peoples budget. Because of this
he is always on the lookout for used and non-working
Z88s. If you have one that you do not intend to use, or
that is no longer working, let him know via email or
postal mail and he will try to see that it gets a good
home, or fixed. He does resell used Z88s and he does
repair them. This also goes for Z88 books, memory
cartridges and Eprom cartridges and other assorted items.
For items you wish to get rid of, he will either freely
take it off your hands, or purchase it if you can come to
a reasonable price based upon its condition and market
price for resell. Thank you for John Rish of HES.
Got a Z88 that needs fixing. He has ways of helping you,
or pointing you in the right direction to get that ZED up
and humming again. Besides his self he knows of several
other places that do Z88 repair for those outside of
North America .
COMPUTER - PRICE LIST
The Quietest and handiest portable page size computer in
Only two pounds and the size of a sheet of paper and less
than 1.5 inches in height..
Runs for 20 Hours on a set of only 4 AA batteries.
Z88 Computer, vinyl carrying case, used in working
Z88 Computer, non-working for parts. $60
To use all of the z88 features you need blank EPROM
Cartridges to store you most frequently used programs.
32K for $25 OR 3 32K for $60, 128K for $52, and 256K
EPROM Cartridges for $87.
128k RAM Cartridge for $56.
32K RAM Cartridge for $35.
512K RAM Cartridge for $100.
One MEG RAM Cartridge for $192.
Z88 to MAC Cables for $8
Z88 Serial Printer Cable for $10.
Z88 Serial to Parallel Printer Interface for $46.
MACLINK to Z88, PC to Z88 Cable, program, cartridge for
Both PCLINK & MACLINK for $50.
QLINK to Z88, QL to Z88 programs $20.
AMIGALINK, AMIGA to Z88 programs $27.
Toppers, molded hard plastic cover to protect Z88 for
Z88 MAGIC, best book and learn to fully use the built-in
BBC BASIC Language of your Z88 computer, limited supply ,
priced at $30. When available
Z88 Source book 3rd edition, with your choice of 3 QL or
PC format disks of P.D. & Shareware programs for the
Z88, for $9.
Z88 Vinyl Carrying Case for $9.
NEW!!! Z88 KEYBOARDS for replacement only $32.
HOME ELECTRONICS SERVICE
5222 Kazen Dr. San Antonio Texas 78219.
210-661-4376 Tuesday thru Saturday only, 6 to 9 P.M.
Internet E-Mail address: email@example.com
Cash, checks or money orders, or COD Payable to:
Add 10% for foreign currency exchange. C.O.D. Fee will be
added to C.O.D. orders. We do not accept credit card
orders, and there is a $10 charge for Electronic Wire
Transfers to our accounts. First time customers, please
allow adequate time for check clearance before shipping.
Page last updated July 20, 2000