6128 cpc to 6128 cpc plus possible or not ???

[FRAGKI-2012]

it is possible to play cpc plus games in a cpc and if it is how ?  
and also is possible to play cpc plus roms games in a classic cpc?
can we also modify a normal game from a classic cpc to rom and play ??
pls post here any information is useful!!!

[Zetr0]

Hello FRAGKI-2012


As far as I know, you wont be able to change / upgrade a stock CPC6128 to make it a 6128+.

The ULA (which it isn't really) is replaced in the 6128+ with a heavily changed custom graphics and memory handling processor.  Personally I think it's awesome but this does break compatibility with some older games.

You can run 464 and standard 6128 games on the CPC6128+ since it has a floppy drive - as long as you are in standard basic, you should be able to load most games from floppy.  Although, as I mentioned earlier there are some compatibility issues with some titles.


I would love to have a CPC6128+, however the urge to hack it into a CPC464 chassis with external dual floppies would be too much for me to bare!

then I gets to thinking about hacking it into a blacked up CPC464+ chassis with external dual 3.5" floppy drives..... .... I am soooo weak....

[TFM]

it is possible to play cpc plus games in a cpc and if it is how ?  
and also is possible to play cpc plus roms games in a classic cpc?

No way. You would need the ASIC chip, and therefore you would have to slaughter a Plus

can we also modify a normal game from a classic cpc to rom and play ??
pls post here any information is useful!!!

Sure. That's no problem. If you have a game (single file, less than 31 KB) I can do that conversion quite easy for you. The tool for doing that is the Inicron Softbrenner. (see http://www.inicron.de). Longer games can be converted too (but I lack time for that ;-))

[Bryce]

All the Plus games (as far as I know) used features of the plus. If you removed and edited these the game would probably work, but that's almost a complete re-write of the code.

Bryce.

[MacDeath]

I tried to launch "the drive belt exorcism" on a CPC (my PLUS overscan graphic)... it didn't worked well... At first the picture almost displayed one second in mode1... then the screen went all... erf... strange and chaotic... I reset in fear, in case it would screw the CRTC or stuff.
Because you know, registers and stuffs

Is it even dangerous for the hardware?

[Bryce]

No, everything in the CPC resets to a defined state when you turn the computer off. There is nothing software could do to permanently damage the CPC. Unless of course it decided to bash the floppy drive heads to their limit for a while until they broke.

Bryce.

[TFM]

Yes, or the kill command to the CRTC or the dead-code for the FDC (which diappears only after unplugging for a while). And you can torture the monitor if you like.

[Gryzor]

I think the monitor can't be permanently damaged, it's been discussed before.


I did half-kill my drive back in the day though, through the magic of random CALLs (ooh, let's see what this does!).

[Bryce]

Yes, or the kill command to the CRTC or the dead-code for the FDC (which diappears only after unplugging for a while). And you can torture the monitor if you like.

I'm intrigued.

What is the "Kill-command to the CRTC" - The CRTC is a large collection of transistors with no permanent latches , flash or any other switch that survives a power down. What exactly does this kill command do?

FDC Dead-code? Same thing. What exactly could you damage here? As soon as the power has gone, the IC returns to its factory state.

Bryce.

[TFM]

The FDC doesn't get harmed permanently, but there is a possibility to screw it in a way that in needs a hard reset.

About the CRTC, yes there is a kill code, but would you use it to find out if it works?

And do you seriously thing that I post that stuff here? No!
Or do you want some c64 user to start coding kill programs for CPCs. No!

[dragon]

About the CRTC, yes there is a kill code, but would you use it to find out if it works?

¿the kill code works on all type of crtc?.i'ts very rare if it works in all crtc included de amstrad crtc emulated.

[TFM]

There was some discussion that it may work only with CRTC 1 and 2. But for obvious reasons people don't like to check that will all their CRTCs

Forget about emulation! How could it work there? The CRTC is _emulated_ so that's no real hardware, it can't be harmed.

You can emulate the FDC problem though.

[dragon]

There was some discussion that it may work only with CRTC 1 and 2. But for obvious reasons people don't like to check that will all their CRTCs

Forget about emulation! How could it work there? The CRTC is _emulated_ so that's no real hardware, it can't be harmed.

You can emulate the FDC problem though.

.

Of course nobody search destroy the cpc .It now work in pc emulator of course.But if it works in the plus,and in the preasic,depend if the problem is in the circuit design.Or is a problem in the  chip desing contain the circuit.

crtc type 1 and 2 can be slighty diferent in the desing.But maybe the two manufactures use the same type of chip  to contain it.

If is a design problem.Thats mean amstrad not based the preasic crtc in the crtc 1 or 2.If is a chip problem thas mean the preasic maybe contain a design based in type 1 or 2 without problems.

[Bryce]

The FDC doesn't get harmed permanently, but there is a possibility to screw it in a way that in needs a hard reset.

About the CRTC, yes there is a kill code, but would you use it to find out if it works?

And do you seriously thing that I post that stuff here? No!
Or do you want some c64 user to start coding kill programs for CPCs. No!

The FDC gets a hard reset every time you turn off the CPC, so it's not really a permanent problem then.

Send me the CRTC info in a PM. I'll give it a try on a spare CRTC.

What exactly does this "Kill code" supposedly do? The Chip doesn't have any fuses, so the only way to kill it would possibly be a hot-spot, ie: a loop that was switching something so often that a certain part of the silicon overheated. But even that is unlikely, because the CRTC is rated at a higher frequency than the CPC could ever feed it with.

Bryce.

[ralferoo]

What exactly does this "Kill code" supposedly do? The Chip doesn't have any fuses, so the only way to kill it would possibly be a hot-spot, ie: a loop that was switching something so often that a certain part of the silicon overheated.

I was thinking about this too. The only thing I can think of is selecting the CRTC along with another device so that they're both driving the data bus at the same time.

[Bryce]

Is that possible on the CPC?

Bryce.

[arnoldemu]

The FDC gets a hard reset every time you turn off the CPC, so it's not really a permanent problem then.

The FDC "kill" is to program it for dma transfer or to program it for specify command and never send the rest of the values.
fdc is either trying to load in dma mode, or it's waiting for the rest of the command bytes.

Something like this does it.

Code Select Expand


out &fb7f, &3

3 is "specify" command.




A lot of Ocean tape games did this to stop the game being transferred to disc.
When you try and access the drive, even after a reset, it makes grinding noises and fails to work.
A full power off is needed to solve it.

To program dma mode you using the "Specify" command and the values, I believe are not killed by a bus like reset, only by power on/off.

Don't know about the "crtc kill"? And I am sure here a reset would clear it.
Are we not talking about a crtc type 2 incompatibility here where R2+R3(hsync)>R0 stops it producing vsync and the keyboard is not scanned and it appears to lock up the cpc?

[Bryce]

Well "Kill" for me and judging from TFMs comments would suggest permanent damage. He seems to think that there is some magic software that would permanently damage the CRTC. I very much doubt this is possible.

Bryce.

[dragon]

Ah I read it in *****.So,you kill the crtc and the Z80.I was wrong.Is a bad desing from Amstrad.

but,they can work in crtc 0.in preasic,maybe not,if amstrad discover the fault.

[Bryce]

Ah I read it in *****.So,you kill the crtc and the Z80.I was wrong.Is a bad desing from Amstrad.

but,they can work in crtc 0.in preasic,maybe not,if amstrad discover the fault.

?? send me a PM with a link to that info.

Bryce.

[MaV]

I'm sure a lot of people are intrigued now.

[Bryce]

The link that Dragon sent me describes a situation where bus contention between the CPU and CRTC (Type 1 only) could occur. If you did what it says, it would cause the CPU and CRTC to both put data on the data bus at the same time, ie: you'd get bus contention - If one of the bits from the CPU were 1 and the CRTC was sending a 0 on the same line (or vice versa), this would cause a local short-circuit. However, both devices have bi-directional data ports and the internal circuitry of the ICs won't be going directly to 5V or GND, so the CPC would maybe pull a few mA more than usual or at worst crash (I'll have to give it a go later to find out), but the chances of damaging either the CPU or the CRTC are minimal if not non-existant.

But maybe TFM knows of another "Kill command" that offers instant destruction?

Bryce.

[MaV]

Or do you want some c64 user to start coding kill programs for CPCs. No!

If anyone writes such a program, the next time I'm at a retro party, I'll charge myself electrically rubbing over a carpet and touch said person's 64 user and joystick ports. I've heard that works wonders ...

But we're here to preserve computers, not kill them, and I'm sure others think the same.

[Bryce]

If anyone writes such a program, the next time I'm at a retro party, I'll charge myself electrically rubbing over a carpet and touch said person's 64 user and joystick ports. I've heard that works wonders ...

Ah, the CIA killer. The difference is, that one actually works

Bryce.

[TFM]

The FDC gets a hard reset every time you turn off the CPC, so it's not really a permanent problem then.

Exactly! But a software reset will NOT help, even using a Restet button is NOT enough. You need to do a real switch off and on. Then it's all good again.
The more "light" version of creating problems here would be just to read a byte from the data bus of the CPC, but in this case a soft-reset is usually sufficient.

Send me the CRTC info in a PM. I'll give it a try on a spare CRTC.

What exactly does this "Kill code" supposedly do? The Chip doesn't have any fuses, so the only way to kill it would possibly be a hot-spot, ie: a loop that was switching something so often that a certain part of the silicon overheated. But even that is unlikely, because the CRTC is rated at a higher frequency than the CPC could ever feed it with.

Bryce.

I don't feel like remembering that. Technically you set a register to a too short value, and you must set another one before to enable the problem. Sceners in France did some "tests" with that years ago.

The FDC "kill" is to program it for dma transfer or to program it for specify command

Well, I just hope this does not inspire people to code some evil code now...

If anyone writes such a program, the next time I'm at a retro party, I'll charge myself electrically rubbing over a carpet and touch said person's 64 user and joystick ports. I've heard that works wonders ...

Well, I know (from sad personal experience) that it does work with a 6128.