Man-In-The_Middle (MITM) Cartridge - Possible batch.

[TotO]

Sorry, I'm new here... But, what is the interest of locking a part of the cartridge???
- If you should provide 512K for games, allow them.
- If you want to put some softwares, make a menu.
- If you want a ROM Board, use a ROM board on the expansion connector and not waste the cartridge range.

A good way to program the cartridge is to make installers from a floppy/HxC/Booster.
Don't confuse ROM board and cartridge use, else you will add water into your wine! 

[Bryce]

@Tot0: You can't use a ROMboard on a GX4000, nor is it easy to have a 256K/512K game on a ROMboard.

@:TFM: As I would be doing most of the testing, I can use real hardware and just remove the IC and reprogram it on the PC if anything goes wrong. But your idea for a second secured area isn't as complicated as you think and wouldn't cost much either, I'll definitely take a look at doing that instead.

Bryce.


Sent from my iPhone using Tapatalk

[TotO]

@TotO: You can't use a ROMboard on a GX4000, nor is it easy to have a 256K/512K game on a ROMboard.

You can't use a keyboard and any drive on a GX4000 too... The GX4000 is not a CPC/PLUS.
That mean, most existing ROMs are unusable on GX, so there are really no interest to limit the PLUS range of computers.
Allowing users to have a 512K free programmable cartridge is far more interesting as a cartridge is intended to fit one or more games inside.

Many users already own a MegaFlash on their PLUS.
But sure, if peoples are OK to lose the half of the cartridges capacity each time for fixed ROM that they should not use...

[CraigsBar]

You can't use a keyboard and any drive on a GX4000 too... The GX4000 is not a CPC/PLUS.
That mean, most existing ROMs are unusable on GX, so there are really no interest to limit the PLUS range of computers.
Allowing users to have a 512K free programmable cartridge is far more interesting as a cartridge is intended to fit one or more games inside.

Many users already own a MegaFlash on their PLUS.
But sure, if peoples are OK to lose the half of the cartridges capacity each time for fixed ROM that they should not use...

I would expect more people to be interested in this on a plus than a gx4000 myself but it should work on both and to have a non breakable emergency OS section seem like a good idea to me. The ability to rescue from a bad flash without having to find a PC or Mac based programmer has to be a good idea. Besides pang is I believe the largest cart game, and it fits in 256kb istr.

Any game that is full or optionally joystick controlled can run from a plus cart. I for example patched "Titus the Fox" and although on a gx you cannot type the level codes everything else works fine.

I'd vote for a protected area of flash for a recovery is.

Craig

Craig

[OCT]

It looks like I'll probably make a small batch of MITM, then after that I'll do a poll of what type of writeable/multiCart I should make.

That should also "defuse" the debate (I had no idea would be held at such length, but hope will be answered anyway) about ROM overrides for X-MEM, a new memory expansion for all CPC.

The MITM was meant as the lowest cost solution I could make because it doesn't require an ACID or any other ICs, which makes it the cheapest way to distribute new software on a cartridge. It was meant for things like Cyber Chicken or other new games that wished to offer a cartridge version without the cost of ACIDs or CPLDs. There are several other cartridges I could make:

1 - MultiCartridge (16x128K ROMs) with CPLD ACID
2 - CPC Writeable cartridge (1x 256K) with CPLD ACID (was actually meant for software development)
3 - 4x 128K Multi MITM

Option 2 is the one I would prefer either, with 2*256K actually:

The Cartridge will have a 512K Flash. The lower 256K will contain BASIC and software similar to ROManager which can be started with an RSX command (much like the OS/Burning Rubber cartridge). This lower 256K part of the Flash is write-protected.
The Upper 256K is free to write what you want to it using the included ROManager software. A small physical switch decides which of the 256K portions gets booted.

Sounds much like the "Bank Exchanger" discussed here some years ago for flipping RAMs in a 6128 (in tandem with a pause button) as a "poor man's Multiface" (and undetectable at that).

if most people find option 2 the most interesting, then I'll look at making that first and forget about making the original MITM completely.

Anything that kickstarts the "emulated-ACID age" by allowing coders to build their own cartridges without hard-hacking (i.e. somehow sacrificing) existing ones is a very welcome leap forward of course.

the whole 512 KB should be freely writable [...] IMHO it would be better to have the software to write to the Cartridge on DISC (or ROM) and allow to write to ALL 512 KB [...] from the POV of a developer.

How about including an emergency/bulk-flash fallback from the PC (even more so if the EEPROM in question is also serially programmable by itself or via existing CPLD snippets) ?

[Maniac]

This sounds like a great idea to me and I'd be very interested depending on how much it is.

[TotO]

@Bryce : If you put the fixed ROMs, then include PARADOS into ROM 7 so everybody will be happy! 

[qbert]

ok Bryce,
I'm in for this batch too ! (if possible)

[dcdrac]

If I understand this correctly this would sit inbetween the cartridge slot and a cartridge and emulate an ACID chip?

[Gryzor]

If I understand this correctly this would sit inbetween the cartridge slot and a cartridge and emulate an ACID chip?

MITM - CPCWiki

[dcdrac]

would definitely be up for one of these