512kB cartridge
10 messages · 2006-11-01 → 2006-12-13 · Yahoo Group era · View archive on archive.org
Participants: Jarek Adamski, Paulo Leite, Bill Loguidice, M. Emrah Oral, Timex
Preserved from the Timex/Sinclair 2068 Yahoo Group (2001–2019), which is no longer online. Text reproduced from the archive.org archive; email addresses masked.
Messages
1. 512kB cartridge
Jarek Adamski · Wed, 01 Nov 2006 14:09
Hello.
I've just got boards for internal 512kB SRAM upgrade. It is
compatible to Larken Ramdisk, and when installed inside, can
also be paged to EXROM, to allow Dock cartridges.
http://8bit.yarek.pl/upgrade/ts.memory/index.html
The same board can be used together with UMCB (Universal
Memory Cartridge Board) to make a 512kB cartridge.
http://8bit.yarek.pl/interface/ts.cartridge/index.html
As any hardware needs the software that could use it, I
suggest the ZXVGS as operating system.
http://8bit.yarek.pl/system/zx.zxvgs/index.html
Along with ZXVGS needs, I have three suggestions for the
cartridge memory structure. Each structure has some limits
and some advantages. I want to ask you, what would you
prefer.
--> 1. 512kB SRAM.
Memory seen in Dock as 8 banks of 64kB. This is quite
compatibile to Larken Ramdisk and internal upgrade. Beside
ZXVGS, the cartridge can be used also to run CP/M, as AROS
or LROS.
ZXVGS can use the memory as a disk, so battery backup is
recommended. ZXVGS uses ~80kB for code and system files,
so ~430kB is for files. There's no option for extra banks,
as the first 16kB used to simulate ROM, must be always
write-protected.
--> 2. 512kB SRAM + 32kB SRAM.
512kB SRAM is seen in upper half of Dock as 16 banks of 32kB
each. The extra 32kB is seen in lower half of Dock and used
to simulate ROM and isn't protected by battery backup. This
is still quite compatibiele to Larken Ramdisk, but not to
internal upgrade. Beside ZXVGS, the cartridge can be used also
to run CP/M, as AROS or LROS.
ZXVGS can use the memory as a disk, so battery backup is
recommended. ZXVGS uses ~80kB for code and system files,
so ~460kB is for files. The area for files can be limited,
giving some extra banks; they are not compatibile to ZX128,
but ZXVGS can use them in a similar way. The 32kB SRAM has
separate write-protection.
--> 3. 512kB EPROM + 32kB SRAM.
512kB EPROM is seen in upper half of Dock as 16 banks of 32kB
each. The extra 32kB is seen in lower half of Dock and used
to simulate ROM. This is not compatibiele to Larken Ramdisk,
nor to internal upgrade. The cartridge can be only used with
ZXVGS or as LROS (programmable) or AROS (fixed).
ZXVGS can use the memory as a disk, in case of PEROM of Flash
EEPROM can reprogramm it. ZXVGS uses ~80kB for code and system
files, so ~460kB is for files. There's no extra RAM banks for
programs. The 32kB SRAM has separate write-protection.
--> 4. Other solution.
Of course other configurations are possible, e.g. 512kB SRAM
plus 512kB EPROM. However, it is harder to build them using
the boards I already have. New boards should be designed for
this, but this is not my goal now. But perhaps you have
interesting idea.
--> Common features.
In case of memory fail, ZXVGS code must be loaded from tape.
ZXVGS is able to use floppy and HDD interfaces, also network
cables. ZXVGS, beside own .V00 files, can load .Z80, .TAP,
and other formats. Also can extend BASIC syntax, adding disk
access or e.g. Interface 1 compatibility.
ZXVGS has compatibile versions for other machines, like Sam
Coupe, Pentagon, ZX+3, and interfaces like MB-02, Timex FDD
System, PL3MEM, ZXATASP/ZXCF soon also for DivIDE. Program
written for ZXVGS will work correctly on all of them, using
disk access, mouse, printer and memory banks.
The price of a 512/544kB cartridge is around $30. Some less
in EPROM version, but in this case you need EPROM programmer.
I would like to know your opinion, as I want to build only
one version and port ZXVGS for it.
Jarek Adamski
2. Re: 512kB cartridge
Jarek Adamski · Thu, 07 Dec 2006 00:49
Hello again.
Not much response is in matter of 512kB cartridge.
After more thinking I've decided to concentrate on
version with 512kB SRAM + 32kB SRAM. It will have
the following features:
[hardware]
- all extra memory seen in Dock,
- battery backup for 512kB SRAM,
- 512kB switchable as 8 banks of 64kB each,
- low 32kB can be replaced with extra 32kB SRAM,
- 512kB can be software write-protected,
- 32kB can be software write-protected independently,
- compatibile to 256kB Larken Ramdisk,
- 512kB SRAM can be replaced with 512kB EEPROM,
[software list]
- all dedicated for Larken Ramdisk,
- ZXVGS LR5 for ZX Spectrum software,
- CPM22QED UPB (CP/M 2.2 compatibile),
- UZI - Unix Z80 Implementation (?),
- SymbOS - www.symbos.de (?),
[features of ZXVGS]
- gives access to ZX Spectrum software,
- can start automaticly after power-on (as AROS),
- is compatibile to other ZXVGS implementations,
- can read and use files like TAP, Z80, SNA, BMP,
- can extend BASIC syntax with disk commands,
- can use the SRAM as disk,
- can offerr banks for applications,
- can also work when SRAM is replaced with EEPROM,
- can be installed from tape in case of fail,
- can use floppy and harddisk interfaces,
- can use file server via communication port,
- will partially emulate ZX128 (banks, AY) by
software patches into TAP and Z80 files.
I'm going to build such cartridge using UMCB and
internal 512kB SRAM upgrade boards.
Then, in case of interest, I'm going to design
next cartridge board, with CompactFlash slot driven
by 8255 (as IDE8255) and above 512kB SRAM.
But perhaps the extra 32kB SRAM will be mapped to
32kB inside the 512kB SRAM or replaced with 512kB
EEPROM.
Any comments or wishes?
Jarek Adamski
3. RE: [ts2068] Re: 512kB cartridge
Bill Loguidice · Thu, 7 Dec 2006 09:30:
It all sounds great, Jarek. The only suggestion that I have is to somehow
make what you're creating a bit better described for those who aren't up on
all the technical or feature-set jargon. You do great stuff, but grasping
some of the complexities are difficult, which is a big reason why I think
there's not a much more enthusiastic response.
======================================
Bill Loguidice, Managing Director
Armchair Arcade, Inc.
(A PC Magazine Top 100 Website)
======================================
<http://www.armchairarcade.com/> http://www.armchairarcade.com
_____
From: Paulo Leite [mailto:[email]]
Sent: Thursday, December 07, 2006 8:59 AM
To: [email]
Subject: [ts2068] Re: 512kB cartridge
Jarek,
it sounds like something I would like to own. How about pricing? How
much will this board cost, any idea?
Paulo Leite
--- In ts2068@yahoogroups. <mailto:ts2068%40yahoogroups.com> com, "Jarek
Adamski" <8bit@...> wrote:
>
> Hello again.
>
> Not much response is in matter of 512kB cartridge.
> After more thinking I've decided to concentrate on
> version with 512kB SRAM + 32kB SRAM. It will have
> the following features:
>
> [hardware]
> - all extra memory seen in Dock,
> - battery backup for 512kB SRAM,
> - 512kB switchable as 8 banks of 64kB each,
> - low 32kB can be replaced with extra 32kB SRAM,
> - 512kB can be software write-protected,
> - 32kB can be software write-protected independently,
> - compatibile to 256kB Larken Ramdisk,
> - 512kB SRAM can be replaced with 512kB EEPROM,
>
> [software list]
> - all dedicated for Larken Ramdisk,
> - ZXVGS LR5 for ZX Spectrum software,
> - CPM22QED UPB (CP/M 2.2 compatibile),
> - UZI - Unix Z80 Implementation (?),
> - SymbOS - www.symbos.de (?),
>
> [features of ZXVGS]
> - gives access to ZX Spectrum software,
> - can start automaticly after power-on (as AROS),
> - is compatibile to other ZXVGS implementations,
> - can read and use files like TAP, Z80, SNA, BMP,
> - can extend BASIC syntax with disk commands,
> - can use the SRAM as disk,
> - can offerr banks for applications,
> - can also work when SRAM is replaced with EEPROM,
> - can be installed from tape in case of fail,
> - can use floppy and harddisk interfaces,
> - can use file server via communication port,
> - will partially emulate ZX128 (banks, AY) by
> software patches into TAP and Z80 files.
>
> I'm going to build such cartridge using UMCB and
> internal 512kB SRAM upgrade boards.
>
> Then, in case of interest, I'm going to design
> next cartridge board, with CompactFlash slot driven
> by 8255 (as IDE8255) and above 512kB SRAM.
> But perhaps the extra 32kB SRAM will be mapped to
> 32kB inside the 512kB SRAM or replaced with 512kB
> EEPROM.
>
> Any comments or wishes?
>
> Jarek Adamski
>
4. Re: 512kB cartridge
Paulo Leite · Thu, 07 Dec 2006 13:58
Jarek,
it sounds like something I would like to own. How about pricing? How
much will this board cost, any idea?
Paulo Leite
--- In [email], "Jarek Adamski" <8bit@...> wrote:
>
> Hello again.
>
> Not much response is in matter of 512kB cartridge.
> After more thinking I've decided to concentrate on
> version with 512kB SRAM + 32kB SRAM. It will have
> the following features:
>
> [hardware]
> - all extra memory seen in Dock,
> - battery backup for 512kB SRAM,
> - 512kB switchable as 8 banks of 64kB each,
> - low 32kB can be replaced with extra 32kB SRAM,
> - 512kB can be software write-protected,
> - 32kB can be software write-protected independently,
> - compatibile to 256kB Larken Ramdisk,
> - 512kB SRAM can be replaced with 512kB EEPROM,
>
> [software list]
> - all dedicated for Larken Ramdisk,
> - ZXVGS LR5 for ZX Spectrum software,
> - CPM22QED UPB (CP/M 2.2 compatibile),
> - UZI - Unix Z80 Implementation (?),
> - SymbOS - www.symbos.de (?),
>
> [features of ZXVGS]
> - gives access to ZX Spectrum software,
> - can start automaticly after power-on (as AROS),
> - is compatibile to other ZXVGS implementations,
> - can read and use files like TAP, Z80, SNA, BMP,
> - can extend BASIC syntax with disk commands,
> - can use the SRAM as disk,
> - can offerr banks for applications,
> - can also work when SRAM is replaced with EEPROM,
> - can be installed from tape in case of fail,
> - can use floppy and harddisk interfaces,
> - can use file server via communication port,
> - will partially emulate ZX128 (banks, AY) by
> software patches into TAP and Z80 files.
>
> I'm going to build such cartridge using UMCB and
> internal 512kB SRAM upgrade boards.
>
> Then, in case of interest, I'm going to design
> next cartridge board, with CompactFlash slot driven
> by 8255 (as IDE8255) and above 512kB SRAM.
> But perhaps the extra 32kB SRAM will be mapped to
> 32kB inside the 512kB SRAM or replaced with 512kB
> EEPROM.
>
> Any comments or wishes?
>
> Jarek Adamski
>
5. Powerup with program or snapshot..
M. Emrah Oral · Thu, 7 Dec 2006 12:32:
Does anybody know if there is a way to use the UMCB boards to store a .z80 or .sna type snapshot file and have the timex2068 start running it as soon as it is powered up ?
Or, is there a way to do that in a 48K spectrum ? I would love to use one of my ZX Spectrums as a dedicated-task machine but I don't know a way to make it execute code from a cartridge, ROM or EPROM on powerup without using any commands, etc.
Possible ?
Bill Loguidice <[email]> wrote:
It all sounds great, Jarek. The only suggestion that I have is to somehow make what you're creating a bit better described for those who aren't up on all the technical or feature-set jargon. You do great stuff, but grasping some of the complexities are difficult, which is a big reason why I think there's not a much more enthusiastic response.
======================================
Bill Loguidice, Managing Director
Armchair Arcade, Inc.
(A PC Magazine Top 100 Website)
======================================
http://www.armchairarcade.com
---------------------------------
From: Paulo Leite [mailto:[email]]
Sent: Thursday, December 07, 2006 8:59 AM
To: [email]
Subject: [ts2068] Re: 512kB cartridge
Jarek,
it sounds like something I would like to own. How about pricing? How
much will this board cost, any idea?
Paulo Leite
--- In [email], "Jarek Adamski" <8bit@...> wrote:
>
> Hello again.
>
> Not much response is in matter of 512kB cartridge.
> After more thinking I've decided to concentrate on
> version with 512kB SRAM + 32kB SRAM. It will have
> the following features:
>
> [hardware]
> - all extra memory seen in Dock,
> - battery backup for 512kB SRAM,
> - 512kB switchable as 8 banks of 64kB each,
> - low 32kB can be replaced with extra 32kB SRAM,
> - 512kB can be software write-protected,
> - 32kB can be software write-protected independently,
> - compatibile to 256kB Larken Ramdisk,
> - 512kB SRAM can be replaced with 512kB EEPROM,
>
> [software list]
> - all dedicated for Larken Ramdisk,
> - ZXVGS LR5 for ZX Spectrum software,
> - CPM22QED UPB (CP/M 2.2 compatibile),
> - UZI - Unix Z80 Implementation (?),
> - SymbOS - www.symbos.de (?),
>
> [features of ZXVGS]
> - gives access to ZX Spectrum software,
> - can start automaticly after power-on (as AROS),
> - is compatibile to other ZXVGS implementations,
> - can read and use files like TAP, Z80, SNA, BMP,
> - can extend BASIC syntax with disk commands,
> - can use the SRAM as disk,
> - can offerr banks for applications,
> - can also work when SRAM is replaced with EEPROM,
> - can be installed from tape in case of fail,
> - can use floppy and harddisk interfaces,
> - can use file server via communication port,
> - will partially emulate ZX128 (banks, AY) by
> software patches into TAP and Z80 files.
>
> I'm going to build such cartridge using UMCB and
> internal 512kB SRAM upgrade boards.
>
> Then, in case of interest, I'm going to design
> next cartridge board, with CompactFlash slot driven
> by 8255 (as IDE8255) and above 512kB SRAM.
> But perhaps the extra 32kB SRAM will be mapped to
> 32kB inside the 512kB SRAM or replaced with 512kB
> EEPROM.
>
> Any comments or wishes?
>
> Jarek Adamski
>
---------------------------------
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6. Re: 512kB cartridge
Jarek Adamski · Thu, 07 Dec 2006 21:52
--- In [email], "Bill Loguidice" wrote:
> The only suggestion that I have is to somehow make what you're
> creating a bit better described for those who aren't up on
> all the technical or feature-set jargon.
Well, writing descriptions isn't my strong side. :(
--- In [email], "Paulo Leite" wrote:
> How about pricing? How much will this board cost,
> any idea?
I want to sell 544kB SRAM cartridges at $37 (ready
for use). Boards for them as DIY kits - $17.
The SRAM+CF slot cartridge would be e.g. $57.
What do you think about it?
I've added some commens...
> [hardware]
> - all extra memory seen in Dock,
This means no internal changes are required and will
work on every Timex Sinclair 2068 (US) and Timex
Computer 2068 (Portuguese).
> - battery backup for 512kB SRAM,
The memory on cartridge can be used as a disk and will
keep its contents, also when power-off and removed from
2068. One battery is enough for 3-5 years.
> - 512kB switchable as 8 banks of 64kB each,
This is quite flexible when used together with Home
RAM, and still simple. One OUT 7,n can switch bank
to n (n=0..7 or 64..71). The switching changes bank
only in Dock chunks, but no Home ones. E.g. selecting
Dock for last 2 chunks will result in bankswitching
of only last 16kB of memory (CPU address space), what
is similar to bankswitching used in ZX Spectrum 128K.
> - low 32kB can be replaced with extra 32kB SRAM,
So the first 16kB of Dock can be used as ROM for
ZX Spectrum and have the same contents while switching
the last 16kB with OUT 7,n. Otherwise all 8 banks would
have to be filled with the same contents, what uses
112kB just to have a copy. Also the Spectrum ROM
contents can be easy patched.
> - 512kB can be software write-protected,
So all the software that does not know how to write
enable the memory, sees it as ROM. This can be used
to simulate LROS and AROS cartridges.
> - 32kB can be software write-protected independently,
The ZX Spectrum ROM cannot be placed in write-enabled
RAM, as executing some code of it produces self-
destruction. Also, by accident (bug in the program) the
ROM contents could be damaged. It is not posible when
write-protection is enabled and most of software will
not know how to change this.
> - compatibile to 256kB Larken Ramdisk,
This is information mostly for Larken software users.
> - 512kB SRAM can be replaced with 512kB EEPROM,
To make cheaper and safer cartridges, SRAM can be
replaced with ROM. In this case the EPROM contents can
be fixed (e.g. a set of your favorite games). Also
no battery-backup, so you can be sure the code written
in memory will not be accidentally damaged. Using ROM
in place of SRAM will limit the software to ZX Spectrum
48K range, as no more RAM banks are available. The
EEPROM (in contrary to EPROM) can be written from
computer level.
> [software list]
> - all dedicated for Larken Ramdisk,
This is information mostly for Larken software users.
> - ZXVGS LR5 for ZX Spectrum software,
See below.
> - CPM22QED UPB (CP/M 2.2 compatibile),
CPM22QED will see the extra memory as a ~400kB disk.
The disk can be shared with ZXVGS, so you can keep
there both Spectrum games and .COM programs for CP/M.
> - UZI - Unix Z80 Implementation (?),
It is multitasking operating system with text console.
A mass storage is recommended. You could make some
experiments with simple software taken from Linux and
use TCP/IP stack (telnet, irc). UZI for MSX-2 computers
is called UZIX and even have a simple browser. This
should also work on 2068 with a communication interface
(serial or bidirectional parallel).
> - SymbOS - www.symbos.de (?),
Multitasking + GUI system, currently working on Amstrad
CPC and MSX-2. I will do my best to get it ported also
for 2068.
There are also two more operating systems, that could
be utilized. Both are for ZX Spectrum. One is +3e,
the second is ResiDOS. They provide extended BASIC
syntax and harddisk support.
> [features of ZXVGS]
> - gives access to ZX Spectrum software,
ZXVGS is like ZX Spectrum with somme extra functions
hooked on RST 8. It can be used for simple things
like loading games, or more advanced like providing
drivers for a hardware like disk, printer, mouse
without hardware compatibility. A program that uses
joystick of ZXVGS will use 2068 joystick on 2068
and e.g. Kempston Joystick on other machine.
> - can start automaticly after power-on (as AROS),
The cartridge can be configured to have special
headers, so the 2068 ROM will recognize it and run.
Otherwise something like OUT 244,16:PRINT USR 32768
would be required.
> - is compatibile to other ZXVGS implementations,
ZXVGS can works on several Spectrum interfaces.
Software that is written or ported for ZXVGS will
not require anymore changes to use other disk
interface or mouse interface, etc.
> - can read and use files like TAP, Z80, SNA, BMP,
ZXVGS has a functionality of resident extrentions.
Special .RZX extentions can convert files used by
Spectrum emulators into real Spectrum.
> - can extend BASIC syntax with disk commands,
The .RZX extentions can also add new commands to
Sinclair BASIC. E.g. the BZX.RZX gives 5 commands:
LOAD * a$ (also: CODE, DATA, SCREEN$)
SAVE * a$ (also: LINE, CODE, DATA, SCREEN$)
VERIFY * a$ (also: CODE, DATA, SCREEN$)
MERGE * a$
CAT
The LOAD command can also change the current path.
> - can use the SRAM as disk,
The extra SRAM can be used just as memory banks or
to store files that have name and length and can
be dinamicly allocated. If you don't have a floppy
or harddisk, the battery-backup will keep the files
until next power-on.
> - can offer banks for applications,
ZXVGS applications are not allowed to use OUTs to
switch memory banks. They must call a function of
operating system or get proper code that is to be
executed in case of memory bank change. It doesn't
matter which port is used to switch memory and
how the switching scheme looks like. Software
dedicated for ZX Spectrum 128K can be patched to
be ZXVGS compatibile and then work both on ZX
Spectrum 128K and also non-ZX128-compatibile
machines like Sam Coupe or 2068 with the 512kB SRAM.
> - can also work when SRAM is replaced with EEPROM,
If the extra memory is used as disk to store some
software and the software don't need to be modified
and if doesn't require extra memory banks, it can be
written in EPROM. (E.g. ZX Spectrum 48K games.)
EEPROM is EPROM that can be written from 2068 level.
(Recomended chip is 29C040.)
> - can be installed from tape in case of fail,
For the first time and in case of fail, you can
fill the battery-backup SRAM from tape of TAP
files. Also you can write to tape or catch on PC.
This is simple way to make a backup, however takes
time (~one hour). In worst case you can have a
rescue audio CD.
> - can use floppy and harddisk interfaces,
ZXVGS will support IDE interfaces like YAMOD.ATBUS,
IDE8255, also the one used in MB-02/DivIDE. In
case of need will also support other interface
(the driver code can be easy replaced). Similar
situation is in floppy interfaces. ZXVGS uses
CP/M filesystem now, but support for FAT is
in plans.
> - can use file server via communication port,
Two of ZXVGS implementations doesn't use direct
disk access - they require another computer that
acts as file server (usually this is Timex FDD
3000 or PC). It is possible to use serial or
bidirectional parallel to conect other computer
and run ZXVGS file server there.
> - will partially emulate ZX128 (banks, AY) by
> software patches into TAP and Z80 files.
The .RZX drivers for .Z80 and .TAP files can
find all suspecious OUTs and known AY players
and patch them to use 2068 build-in hardware.
Jarek Adamski
7. Re: Powerup with program or snapshot..
Jarek Adamski · Fri, 08 Dec 2006 01:45
--- In [email], "M. Emrah Oral" wrote:
> Does anybody know if there is a way to use the UMCB boards
> to store a .z80 or .sna type snapshot file and have the
> timex2068 start running it as soon as it is powered up ?
> Or, is there a way to do that in a 48K spectrum ?
For Interface 2 (that is kind of cardridge system for ZX
Spectrum) was developed a 64kB cartridge. The cartridge
has four banks of 16kB, switched by delay circuit.
http://8bit.yarek.pl/interface/zx.interface2/
Just after power-on first bank is available. A small code
is copied into RAM, unpacks rest of data and waits for
2nd bank that becomes available after ~500ms. Data is
also copied and waiting continues to 3rd bank to be
paged-in. Next copying and waiting for the 4th bank
follows.
There's also a PC software that can convert a .Z80 file
into the cartridge contents and adds deploy code.
Similar way is also possible for 2068. However, the
contents of first bank must behave like LROS cartridge,
while the last one (4th) must be Spectrum ROM.
Another solution is to use the 64kB EPROM to fill
whole Dock and have AROS header at 32768.
> I would love to use one of my ZX Spectrums as a
> dedicated-task machine but I don't know a way to
> make it execute code from a cartridge, ROM or
> EPROM on powerup without using any commands, etc.
> Possible ?
You need to find an Interface 2 or build the
cartridge slot of it using two slots and set of
wires. Then build the 48kB/64kB cartridge.
Jarek Adamski
8. Re: [ts2068] Powerup with program or snapshot..
Timex · Fri, 8 Dec 2006 10:25:
On Dec 7, 2006, at 8:32 PM, M. Emrah Oral wrote:
> Or, is there a way to do that in a 48K spectrum ? I would love to
> use one of my ZX Spectrums as a dedicated-task machine but I don't
> know a way to make it execute code from a cartridge, ROM or EPROM
> on powerup without using any commands, etc.
> Possible ?
I would like to have is Zebra Copy to copy tapes to disks in Timex FDD.
Johnny Red, Portugal
9. Timex FDD utils
Jarek Adamski · Fri, 08 Dec 2006 19:05
Hello!
--- In [email], "Johnny Red (Timex)" wrote:
> I would like to have is Zebra Copy to copy tapes to
> disks in Timex FDD.
See the toolsdsk.zip/toolstap.zip and 80utils package
(resides in Timex FDD 3000 RAM).
http://8bit.yarek.pl/system/zx.tosa2/index.html
Jarek Adamski, Poland
10. Re: 512kB cartridge - with IDE and CF
Jarek Adamski · Wed, 13 Dec 2006 00:37
I've started design of the compact IDE interface. It is
based on IDE8255, that uses 8255 PPI and its MODE1 while
reading. Now has IDE40 slot at top side and CompactFlash
slot at bottom side. It will be a bit trickly to mount
it, but both the CompactFlash and ordinary HDD or
CD-reader can be used.
Without the port address decoder it occupies 33mm × 63mm
on a board. A board that can be inserted into 2068
cartridge slot can be up to 77mm × 65mm.
When the cartridge door is to be closed with
CompactFlash inside, 50mm must be reserved for it and
the IDE interface. This leaves 27mm for the other
features, like port decoder, SRAM and battery. This
is not much space.
Have a good time.
Jarek Adamski
Indexed under
Cartridges, EPROM & dumping · Disk & floppy systems (Larken, AERCO, Oliger) · Pico / modern interfaces (UnoDos, etc.)