how many z380 are there?

Champion (457)

26-09-2021, 12:14

Metalion wrote:

I don't know if that's the case with this project, but I'm dreaming about a cartridge that would, in effect, replace the Z80 with a Z380. All software (and BIOS) would be executed through the Z380.

Not sure if it could be done, though, because I don't think the standard cartridge interface is capable of doing that.

Unfortunately the MSX cartridge slot is missing the signals needed to do that (/busreq and /busack). Next to that MSX computers with buffers on the slots also make it impossible as the address and signal lines only go out to the cartridge and cannot go in (only datalines are bi-directional).

Par erpirao

Paragon (1314)

26-09-2021, 13:37

as an external accelerator, we could have the slt-turbo, if sharksym dares to manufacture and sell it outside of korea.
The truth is that it is very interesting how that device has done and how it does a bypass of the bios, that if it requires an MSX with Engine ..
SLT-Turbo

Par o.geerdink

Hero (588)

27-09-2021, 12:36

I have it but never got it working, did receive a new BIOS rom but still didn't seem to do anything (I was told it would do something by just inserting it into a msx).

Put it in the slot expander (that came with it) and put that in a msx2. Maybe one day I will get this to work.

Par hit9918

Prophet (2927)

27-09-2021, 23:19

lintweaker wrote:

Unfortunately the MSX cartridge slot is missing the signals needed to do that (/busreq and /busack).

It is possible with a cartridge that generates code for the motherboard z80. Then it can acess all ports and all slots, fully compatible.

Par sdsnatcher73

Prophet (3850)

28-09-2021, 10:45

hit9918 wrote:

lintweaker wrote:

Unfortunately the MSX cartridge slot is missing the signals needed to do that (/busreq and /busack).

It is possible with a cartridge that generates code for the motherboard z80. Then it can acess all ports and all slots, fully compatible.

Basically turning the original Z80 into a bridge between all the internal hardware and the Z380, but that would mean existing code would not run on the Z380 unless there is some process overseeing the running code and changing any I/O requests dynamically into code running on the Z80 and reading/writinh the data to/from the Z80 instead

It might be possible if this code would run in 32bit mode on the Z380 and the MSX BIOS on the card could catch these I/O requests (all that without too much knowledge of how the Z380 works ).

Par Metalion

Paragon (1622)

28-09-2021, 14:04

Is the pinout of the Z380 even remotely compatible with the Z80 ?
Address bus and data bus aside, of course.

EDIT : The Z380 has a 100 pinout configuration, vs 40 for the Z80.
Removing address bus and data bus leaves 52 pins on the Z380 vs 16 on the Z80.
So I guess the answer is no.

Par lintweaker

Champion (457)

28-09-2021, 14:31

Metalion wrote:

Is the pinout of the Z380 even remotely compatible with the Z80 ?
Address bus and data bus aside, of course.

EDIT : The Z380 has a 100 pinout configuration, vs 40 for the Z80.
Removing address bus and data bus leaves 52 pins on the Z380 vs 16 on the Z80.
So I guess the answer is no.

Some glue logic is needed to make a Z380 talk to 'old' hardware. E.g. Z380 does not have the /mreq signal but does have /mrd and /mwr. And at least Z380 /m1 is not the same as on Z80.