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Topics - gflorez

Pages: [1] 2 3 4
1
I want to try the external cartridge bay that Zozo sugested. But I need some schematics.

2x 74ALS138
1x 74LS32

First 74LAS138:
/E0 and /E1: /MREQ
E2: /RFSH
A0: A19
A1: A20
A2: A21
The 8 outputs are valid for 8x512K memory areas:
/Q0: 00H-1FH
/Q1: 20H-3FH
/Q2: 40H-5FH
/Q3: 60H-7FH
/Q4: 80H-1FH
/Q5: A0H-BFH
/Q6: C0H-DFH
/Q7: E0H-FFH

With the second 74ALS138 divide one 512K are for a 64K areas:
/E0 and /E1: /Qx from first 74ALS138
E2: +5V
A0: A16
A1: A17
A2: A18

If using /Q0: 00H-1FH from first 138, then the outputs of the second:
/Q0: 00H-03H
/Q1: 04H-07H
/Q2: 08H-0BH
/Q3: 0CH-0FH
/Q4: 10H-13H
/Q5: 14H-17H
/Q6: 18H-1BH
/Q7: 1CH-1FH

The selected output will be the new /CART signal. Using Q0 from the first, and Q2 from the second, then the new external cartridge will be at 08H-0BH, next to the original.
One gate from the 74LS32 make the /CART&RD signal.

Also need a 7805 (or compatible) or a +5V from bus card.

Ok thanks. I will study it and more questions will follow, for sure....

Similar decoding is made inside DAVE:



I understand that /ROM is no more necessary, with your modified EXOS a ROM can exist on any 16kb boundary(Segment).

/CART&/RD  at B3 on the Cartridge Bay is decoded outside DAVE:

23096-0
--------------------------------

Ok, I will make a prototype of an External Cartridge Bay with all the 4MB addressing range options selected by jumpers. It could also be useful for testing a lot of other projects, to put 1 to 4 16KB RAM/ROM segments exactly and easily on the position where we want. A 4 socket 16KB cartridge PCB would be useful for it.

I only see a drawback, the code of the SD-Reader has to be re-written "segment-position-aware" to work externally. By now it only works at 04-07 segments because the RAM window is accessed at 07. The same with the MIDI interface.

2
Illesztések / A SymbiFace3 közel van az Enterprise-hoz!
« on: 2019.February.19. 09:46:27 »
Hans Tillema (TMTLogic), a Prodatron által elkötelezett, a harmadik reinkarnációjában a SymbiFaceIII nevű CPC számítógépekre vonatkozó all-in-one kártya fejlesztésének utolsó szakaszában van.

"Gondolod, hogy van-e igény a kártya számára az Enterprise számára?
89 euróba kerül

A következő jellemzőkkel rendelkezik:

2MB Ram
512kb FlashRom
mp3
codec voip
tmtnet
RTC
OLED
fat32 usb stick
usb egér

és több.."

"Elfelejtettem
wifi
sd kártya roms egy belső tárolóhoz "

Egyszerűen, ha keres a "symbiface" -on a Google-on, megtalálhatja a korábbi verzió, a SimbiFaceII leírását.

Nem volt egy első verzió, de egy olyan nevű CPC IDE nevet készített, amelyet egy német fejlesztő DR. ZED segítette a CPC-felhasználók Octoate, TFM és Tolkin.

A SymbiFace II a CPC IDE korszerűsítése volt,
a Prodatron elkötelezte magát a DR-nek. ZED.

A SymbiFace II összes funkciója, amelyet a SymbOS CPC-portján hajtottak végre, így ezúttal a Prodatron ugyanezt teszi a hozzáadott jellemzőkkel.

Ez egy YouTube-videó, ahol a SymbiFace CPC szinte befejeződött.

Hans hozzáteszi ezt:

"A SymbiFace végső alakja a Vállalat számára attól függ, hogy mit szeretne, melyik IC-k fogják építeni.

A CPC firmware-je szinte készen áll a tesztelésre, úgy gondolom, hogy az Enterprise fejlesztése is rövid lesz.

Szükségem lesz egy csomó információra és segítségre van szüksége a Enterprise ROM-ok és alkalmazások írásában, de a CPC Z80 forráskódja a fejlesztőktől lesz elérhető.

Egy másik SD-kártyát is hozzá tudtam adni, és ha 2MB-os RAM nem annyira fontos, több memóriát tudok hozzáadni a Roms-hoz. Beállíthatom.

Én is eltávolíthatom az USB egeret, amint saját szabványod van, és ezek a változások esetleg olcsóbbá teszik a kártyát.

A cél az, hogy ne érjen el drágább, mint a jegyzett ár "

Hans azt akarja, hogy vitatkozzunk az eszközök elhelyezéséről vagy eltávolításáról a SymbiFace listán, még akkor is javasolhat más vagy másokat. A SymbiFace for Enterprise még teljesebb lehet, mint a CPC-verzió. Egy új projekt, amely kihasználja korábbi munkáját.

3
Interface / New Bus Expander, how to use it.
« on: 2019.January.21. 14:21:25 »
22562-0

I want to give you some recommendations of use for the Bus Expander on its second version, but if you find difficult to understand this, please ask Zozo about how to prepare the Bus Expander to work with your classic card expansions.

This card is a modern copy of the Hungarian made Bus Expander designed long ago by Gyula Mészáros, but with a particularity: by default the cards plugged in the slots will feed its +5v from the 7805 regulator fitted in the Bus Expander from pins 4A/B of the connector.

But all the classic Hungarian expansion cards have its own 7805 regulator and they will not work directly, so you have to do a modification on the bottom side of the Bus Expander. The slots come unconnected from +9v on the 33A/B pins of the connector, but there are a selector at the bottom side on every slot to permit this only joining two cooper pads with a drop of tin. Then, the modified slot will be only used for a classic expansion.

22560-1

Previously, you have to solder a DIL row of pins on the EDGE male connector of your classic card expansion. I will distribute the Bus Expansions only fitted with DIL connectors. But there are on the card holes to solder EDGE connectors, not provided by me.

The Enterprise power supply comes on +9v 2Amp or 1,3Amp variants, so, when all the equipment is connected, if you experience undulations on the screen, probably you need to connect a secondary power supply on the Bus Extension auxiliary power connector.

Also, every 7805 regulator can feed up to 1Amp of current, and this can be insufficient to feed the three slots when all of them being populated. This doesn't applies to slots modified for classic expansions as they produce its own +5v. The rear connector also doesn't count, it only feeds from +9v.

To overcome this I recommend to substitute the 7805 regulator that comes installed (the chip with screw and heat sink) with a 2Amp TracoPower regulator(I don`t recommend the 1Amp variant, of similar price):  https://hu.rs-online.com/web/p/kapcsolas-szabalyozo-es-kiegeszito/1616642/



The chip has the same pinout than the 7805, and I have used it for decades on my Enterprises without problems. This chip works at ambient temperature, is more energy efficient and doesn't burn your fingers...

On this second version of the Bus Expander, holes have been added to fit an array of 4,7K pull ups to the Data bus, to overcome some problems of shadow segments when a Ram expansion or Turbo mode are fitted to the computer. You can see the pads zone near the expansion connector.


4
Hardware / SymbiFace3 is near your Enterprise...
« on: 2018.October.27. 14:12:42 »
Hans Tillema, from TMTLogic, commited by Prodatron, is on the final stages of development of  an all in one card for CPC computers named SymbiFace in his third reincarnation.

It will have the following features:

"Do you think there is a demand for this card for the Enterprise?
will cost around € 89

2mb ram
512kb rom flasable
mp3
codec voip
tmtnet
rtc
oled
fat32 usb stick
usb mouse

and more.."

"I have forgotten
wifi
sd card for roms an internal storage"

5
Interface / Philips Music-Module MSX cartridge test
« on: 2018.September.04. 21:11:35 »
While I wait for the GFX-NINE graphics cartridge I have got another I/O MSX cartridge to play with.(only to demonstrate how well the M-Slot adapter works...)



As you can read on the MSX.org web page, this was an all-in-one music cartridge released for all the MSX computers.

Its features are :


 -   32KB of sampleRAM for the ADPCM unit
 -   MIDI interface (with IN/OUT/THRU connectors)
 -   Proprietary connector for music keyboard (NMS-1160)
 -   2 RCA mono Audio-out connectors
 -   built-in microphone (mono)
 -   1 RCA external microphone connector (mono)
 -   volume adjuster (sample volume)
 -   1 audio-in RCA connector (mono, to sample from a "line"-source)
 -   built in software (Music-BOX, CALL MUSICBOX)

Impressive, isn't it? but its main drawback is that it only outputs mono sound. Inside, it has the Yamaha Y8950,  sound processor installed. Here follow  the main specs:

-Realistic FM sound generator compatible with YM3526(OPL)
-Simultaneous play of 9 tones or 6 melodies
-AM vibrato
-4-bit ADPCM voice analysis/synthesis circuits(on other descriptions they say it is an 8 bit ADPCM)
-AD/DA converters
-Up to 256KB of Ram can be attached for ADPCM data storage(only 32KB installed on this cartridge)
-8 bit input/output ports for simple piano keyboard scanning.

Philips used to subcontract its products, and on its MSX range this module wasn't an exception. It was created by  Richard Watts Computers LTD(Music Sales LTD), who, commissioned by Commodore, also made a similar product for the C64.

It was sold only in Europe, but it  had great success.(Appears now and then on Ebay.)

Often it was offered in a bundle with a passive 61 keys piano keyboard(hollow, without added electronics). I have used a cheap Chinese toy piano to replicate its functions...  

It is a very big cartridge, the SE-ONE and GFX-NINE ones are only a little higher than the black zone in the case...

At the end of its Service Manual there is a MSX Basic listing to test its features. Is this program what I will translate to IS Basic to try its features more easily.

It uses ports 00, 01, 05, 10, C0 and C1.  00 and 01 can collide with the 'Meszaros' Serial card, scarce today. But 10 is a problem when the EXDOS interface is connected. 05, C0 and C1 are still unused.

Here is the MSX Basic listing as it comes in the manual:

6
Kijelző / GFX-NINE, betolakodó grafikus cartridge-ben
« on: 2018.August.16. 22:00:20 »
Ismét segítségre van szükségem a szöveg fordításában, kérlek ... Kösz Tutus, Geco.

----------

Again I need your aid translating the text, please.... Thanks Tutus and Geco.





Hamarosan megkapom az új TMTLogic MSX grafikus kártyát. Ezúttal nehezebb lesz Enterprise-ra dolgozni, mert ezt a vadállatot teljesen IN és OUT Z80 parancsokkal kell programozni. Mivel már rendelkezem az M-Slot-tal, ezért nem kell küzdenem azzal, hogy hogyan tudom csatlakozni a számítógéphez ... Van egy régi V9990 könyvtár amely segíthet nekünk új programokat készíteni..

A GFX-NINE kártya története hasonló z SE-ONE-éhoz, ez egy klónja szintén a Sinrise által tervezett kártyának, a Sunrise Svéd és Dán MSX fejlesztők csoportja a 90-es évek közepéből, a kártyan GFX-9000 néven futott, ez volt az utolsó amatőrök által elkövetett hardver fejlesztés MSX-re, amikor az Amigák, és az Atari ST-k uralkodtak.

A történet szerint a Yamaha V9990 chip a "butított" verziója a V9978-nak, a VDP chipet (Video Display Processor) az MSX3-hoz tervezték, amely sose látta meg a napvilágot.

A Yamaha V9990 evaluation boards-ot MSX-hez és PC-hez ajánlották.

Saját szemszögemből ez a chip teljes kudarca volt a Yamah-nak, mivel nem találtam semmilyen eszközt, amit e köré építettek volna, kivéve ezt a fajta bővítő cartridge-et. Nem meglepő, könnyű teljesen új chipeket találni kínában.

Sunrise saját GFX-9000 kártyáját az Evaluation board "butított" verziójának tervezt, ahogy ebből kiderül: early document

Ami érdekel ezekben a spéci MSX kártyákban, az, hogy hatékonyan működnek EP-n, és támogatottak a SymbOS (Prodatron) által már a kezdetektől.
A SymbOS-nek V9990 verziója is létezik MSX-re, és tavaly óta béta verziója CPC-re.
Most itt a lehetőség, hogy saját V9990-es SymbOS-unk legyen, a LEGGYORSABB, ha 10MHz-es Enterprise-on fut...

A luxus SE-ONE-on Hans nem csupán lemásolta a kártyát, hanem a leküzdötte a felmerülő áramköri problémákat is, és át is tervezte, hogy alacsony profilú dobozba is beférjen.

Mondhatják "ez már többé nem Enterprise", de úgy gondolom, hogy szeretett gépünk ilyen erős lehetne, új, és régi egyszerre.

7
Interface / GFX-NINE, the intruder graphics cartridge
« on: 2018.August.16. 20:23:20 »


Soon I will receive the new TMTLogic MSX graphics cartridge. This time it will be harder for me to make it work on the Enterprise, because this beast has to be programmed entirely by IN and OUT Z80 commands. At least I already have the M-Slot, so I don't have to struggle thinking how to connect it to our computer... There is an old V9990 library that can aid us to make new programs.

The story of this GFX-NINE cartridge is similar to the story of the SE-ONE, it is a clone of a cartridge also designed by Sunrise, a group of Swish and Dutch MSX developers on mid 90s.  Its name was GFX-9000, and was the last amateur attempt to update the MSX hardware on times where the Amigas and Atari STs where the sovereigns.

The legend says that the Yamaha V9990 chip is a cut-down version of the V9978, the VDP chip (Video Display Processor) designed for the MSX3 series of computers, never released.

Yamaha offered evaluation boards of the chip for MSX and PC systems.

From my own point of view, this chip was a total failure for Yamaha, as I haven't found any device  built around it except this type of add-on cartridges. Not surprisingly it is easy to find full batches of new chips on China.

Sunrise made their GFX-9000 cartridges as cut-down versions of the Evaluation boards, as can be  understood from this early document.

My interest with this special type of MSX cartridges is that they effectively work on an Enterprise, and secondly that they where supported by Prodatron from the first time. There is a V9990 version of SymbOS for MSX computers and, since the last year, a beta for the CPC series. Now it is possible to have our own V9990 version of SymbOS, the fastest, if run on a 10Mhz Enterprise....  

As on the luxurious SE-ONE, Hans has not merely copied the Sunrise cartridge, he has overcome the problems of the circuits with a logic analyser, also redesigning the card to fit on a  low profile case.

Somebody can say, "this will be no more an Enterprise", but I think the contrary, our loved computer can be this powerful, new and old at the same time.

8
Hardver / M-Slot (MSX konverter kártya)
« on: 2018.July.06. 01:55:52 »
Itt kezdődik egy olyan téma, amely már létezik a fórum angol oldalán.

Először is tudnia kell, hogy a Z80 processzoron alapuló egyéb számítógépek többet osztanak, mint amennyit ugyanazt az architektúrát feltételez.

A memória hozzáférés egészen más lehet, például MSX, CPC, Spectrum vagy Enterprise számítógépek, de a Z80 a rendszer bővítésével kommunikál ugyanazon portrendszeren keresztül.

Nagyon szerencsések vagyunk, hogy az MSX számítógépek csak az első 256 port címét használják, mint az Enterprise,
és hogy számos nagyon érdekes MSX patron olyan portcímeket használ, amelyeket egyetlen klasszikus Enterprise bővítés sem használ.

Az érdekes dolog az, hogy a SymbOS létrehozója, a Prodatron támogatást nyújtott néhány patronhoz az MSX verzióban, és ez a kód szerepel az Enterprise operációs rendszer verziójában.

Előzményekként megemlíthetjük, hogy a Prodatron tavaly megbízta az MSX patronok CPC verzióinak létrehozását, például a GFX9000 cart vagy az MP3 cart, mindkettőt a Sunrise-nek, kivéve az MSX patronok számítógépes CPC-hez való közvetlen illesztését.

----------------------------

Here begins a topic that already exists on the English page of the forum.

First, you need to know that other computers based on the Z80 processor share more than you assume the same architecture.

Memory access can be quite different, for example, on MSX, CPC, Spectrum or Enterprise computers, but the Z80 communicates with the extensions hardware using the same port system.

We are very lucky that MSX computers only use the first 256 port addresses as Enterprise does, and that a number of very interesting MSX cartridges use port addresses that are unused by any of the classic Enterprise Enhancements.

The interesting thing is that the SymbOS creator, Prodatron, has provided support for some cartridges in the MSX version, and this code is included in the Enterprise operating system version.

In the past year, Prodatron has commissioned the creation of CPC versions of MSX cartridges, such as the GFX9000 cart or the MP3 cart, both from Sunrise, and also an adapter of MSX cartridges to CPC bus expansion.

9
Maintenance / Bad cut on the Expansion Connector
« on: 2018.June.22. 11:58:58 »
Just because I am actually testing the bus expanders, I have discovered one more perturbing error on my second Enterprise.

I already found other error on the rear connectors of the same unit some time back.

Observe these pictures:

21309-0
21311-1

You can realize that the cut of the board is displaced at least a milimeter to the rear in this unit. In the past this prevented the correct operation of the Bridge connector+Hardware Spectrum emulator on this Computer, but then I used to think that it was by other causes, because some times it worked flawlesly(it touched correctly the pins).

The solution is easy, the bus expander for this unit has to be trimmed at the sides to adapt it to the error. But then it will no longer be interchangeable...

Sorry, bad pictures...

10
Display / External colour tests
« on: 2018.June.03. 19:25:08 »
Yesterday I attended a closed doors retro-computer convention. It was a reunion of Retrowiki members on Navia, near Oviedo at north of Spain, just at the Cantabrian sea, about 500Km from Madrid.

Of course I was the only assistant who carried Enterprises, not the others fault, as it is considered a very complete computer, but it was scarcely sold on our country. On the other side, most members of the Spanish website are interested in more than one computer model, not like me....

There was a variety of micro-computers displayed, from  Spectrums on all their many incarnations(even Timex-Sinclair),  to Amstrads CPC PCW CPC+, Oric, MSX, Amiga, Atari, Mac, Silicon Graphics, Raspbwrry-pi, and a lot more that I can't remember now.

But the main intention of the annual reunion is to present, debug and develop new gadgets for the computers, like memory, SD adapters and other peripherals.

I brought my humble contribution, the bus expander and the M-Slot prototype. One of my friends, Dandare, showed a preliminary version of the Dandanator for CPC, that consist on a cheap card(less than 15 Euro) with 512KB FlashRom, able to hold 10-15 games. It is able to load a game instantaneously, and save/load its progress. Nearly 1500 Dandanators for Spectrum have been created up-to-date. Another friend, Habi, presented a card that provides colour and sound to the Amstrad PCW(a silent, only green phosphor monitor CP/M computer, intended only for business).

Talking with Habi  about how a FPGA interprets the colour of the only green screen, the conversation turned to how the microcomputers of that era codified the colour, halving the resolution when doubling the colours. This though lead us to how clever is the design of the LPT table on the Enterprise. Habi himself owns an Enterprise, and asked me how the colour inputs on the expansion connector works. I answered what I know about the tests made by Balaguesz. Then he said so quiet: "what if we try to do the same with my 20 euro FPGA? I can take advantage of the already written core for the PCW."

I showed him the Nick description document on Zozo's page an he read it briefly.

The main problem interfacing FPGAs with retro-computers is that they work on 3.3v, but fortunately he has a bridge card that makes the signal conversion.  He gave me some Dupont cables and asked me to connect the required signals to the rear connector of my bus expander.

He needed:

-14MHz clock
-Horizontal and Vertical synchronisms
-Ground only, as the FPGA has its own power supply
-EC0 to EC3
-/EXTC

After a few problems with the Dupont cables connection, soon we had reception of the output signals on the FPGA. Then he made some corrections on the code and tried to compile it. Take in account that the code of a FPGA describes how the real hardware is emulated inside, so it has some strict rules that must be observed. It took about 2 minutes to completely compile the code. But we repeated the procedure several times, because at first time it didn't work as expected. Soon he discovered the real resolution of the Enterprise, did some corrections and after only one hour trying we started to see the effects on the screen.

21242-0

21244-1

21246-2

There is some noise on the injected data, probably due to the proximity of other retro-computers.


11
Hardware / SE-ONE music file player
« on: 2018.April.12. 10:13:28 »
I have connected an I/O MSX cartridge named SE-ONE, from TMTLogic, and it has been correctly detected by the EDCW hardware searcher:

20686-0

Sorry for the ugly picture....

12
Interface / M-Slot (MSX cartridge adapter)
« on: 2018.March.13. 11:13:48 »
I'm going to put here my thoughts about how to connect a MSX cartridge to the Enterprise expansion connector(Bridge or bus expander).


But first of all we must know what are the main facts, similarities, differences and lacks of the connectors and architectures:

Something about MSX interfacing has been written on the SymbOS thread, so I will put here only a link.

-We have been very fortunate that the Z80 ports used by the most interesting MSX I/O cartridges have not been used on Enterprise expansion projects, so there would be no collision there. Also, just because of this, Zozo says that 14 bit address could be used on this special case to preserve the Enterprise ports left of the bottom 256. We must return to think about this more deeply.

-The Enterprise uses a card style edge connector of 74(37x2) pins at 2,54mm pitch, while the MSX slot uses the very same connector but with only 50(25x2) pins. The original Enterprise bus expander had a 4 pin code on every bus slot to deal with Z80 ports collision, but it was never released nor its information distributed, so the Hungarian developers created their own parallel standard, similar to the PC slots arrangement or the MSX I/O slots. Curiously, the MSX cartridge slots are also coded, but only for memory, up to 4MB, the same limit as the Enterprise.

-Both connectors have the complete Z80 bus(address, data) and signals on them, so it is only a mater of rearranging the pins, but to have a working MSX slot we must also deal with the specificities.

For example, the Hungarians developers  based their bus expander on the EXDOS card, that doesn't make use of +12v and -12v(commonly used on amplifiers on audio cards), so they didn't populated pins A37 and B37 as was mandatory on the lost&found original project. But these are necessary for the MSX audio cartridges, so these voltages have to be implemented on a new project.

Also, every audio MSX cartridge returns mono sound to the main-board by a pin. We know that the EP has been provided with two pins for stereo audio return(and mix?), but, ¿does somebody know the level of the sound and how to protect the Enterprise?

13
Programming / Mapping and disassembling C64's Maniac Mansion
« on: 2017.October.22. 00:17:25 »
The Point&Click adventure game genre started on Maniac Mansion for the C64 and spread easily over other 8 bit computers based on the 68XX processor family. Then the game and the genre jumped to the 16 bits without even touching one Z80 computer.

Mouse control wasn't planed on the 1987 release, after all that was the precise time when the device was being introduced. But also because in the C64 memory didn't remain space to put the needed mouse driver.  

Later in 2009, a C64 enthusiast nicked enthusi made an attempt to put mouse control on the C64 game.

But the best is: to do it he reverse engineered completely the game. First he removed the special disc format, and then he carefully placed all the found data on a NeoRam-GeoRam cartridge image. He explains the process on his release instructions. A pity he didn't free the code obtained.

The special game image can be downloaded from here. I have installed the ViceC64 emulator, as it supports the NeoRam-GeoRam cartridge emulation, and it works flawlessly. Once the image is loaded it must be launched with  SYS 57000 or SYS 57E3. He has added mouse control, some extras and has fixed the flagrant errors found, but the game works exactly the same.

As you already know, this game is based on a script language and parser named SCUMM, this first time version 0. The subsequent versions up to 2 where made for the other computers conversions, removing the "C64 only" characteristics on Maniac Mansion(like SID music, side scroll, hardware sprites or graphic modes) to make SCUMM more portable. Later on, new games added more and more characteristics to SCUMM, up to version 8.

The NeoRam-GeoRam cartridge is a Ram expansion, but the NeoRam version has a battery to maintain the memory content. It works paginating 16Kb segments like the Enterprise memory. I have peeked the image with an Hex editor, and all the information is there completely accessible without protections. Probably even the SID songs can be easily extracted and converted.

14
Interface / Enhanced Bridge connector
« on: 2017.October.02. 01:57:39 »
I am thinking....

Please correct me if I'm wrong:

The old Bridge Connector was the short cheap version of the original never released Expansion Motherboard.

But the Bridge doesn't have the line protection circuits that the Expansion Motherboard got planed. It was intended for only one expansion card, the EXDOS controller.

Later, on the 90's, the great Gyula Mészáros released his Bus Expansion card and his superb expansion cards line. For it he followed the EXDOS schematics,  adding some line protections, slightly different to the lost original project. Due to the lack of original schematics, Mészáros didn't correctly use the expanded pins on the Bus, SA0, SA1, SA2, +12v and -12v. On all the five slots of the expansion card, SA0 was fixed to +5v and SA1 and SA2 to ground. +12v and -12v where left unconnected (Now is too late to re-implement the SA 3 bit code on the cards, I think, only the original EXDOS card and an external memory expansion card, never released, use it. Also, it seems that no card uses the +12v and -12v lines).


----------

Now that the EPNET time is approaching, I would like to additionally connect to my EP the two cards I own: Pear's Spectrum emulator clone and  Microteam EXDOS clone. In fact, my Microteam card, supplied by Zozo, has an extra expansion bus, similar to the short one that the EPNET card has.

But I will love an Enhanced Bridge Connector with line protections, i. e. like the EXpansion Bus card but with only one slot. Why? because I would like to have al the cards encased and stacked horizontally like the original concept design....

Not so neat, but with some sort of flexible cable and connectors, I would have well organized the desktop....

I was only dreaming...

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Other topics / softcart© cartridges.
« on: 2017.September.04. 11:01:28 »
I have purchased(not cheap...) four cartridges from an Hungarian seller, thinking by their aspect that they where some form of copy or clone from the original.

But to my surprise, they are completely original 16KB cartridges, both the case and the card inside:

18752-0

18753-1

I have searched for information here and on the Museum page, and have found that the "softcart©" range of products where offered at the Centrum store on fall 1987.

As you can see, they have a similar sticker than the EP64 cartridge but with the "softcart©" logo on the side.

Internally, the only modification is an Eprom glued to the socket.... thieves watching over their spoil.

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