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General Category => Amstrad CPC hardware => Topic started by: Prodatron on 23:12, 15 September 17

Title: MSX-to-CPC I/O hardware adapter
Post by: Prodatron on 23:12, 15 September 17
TMT Logic from The Netherlands...
http://www.tmtlogic.com (http://www.tmtlogic.com)
...is currently planning to produce an adapter for the CPC, which allows to connect any I/O based MSX hardware.
Many MSX hardware is memory mapped/slot based, which would be quite complicated.
But there is also a very interesting selection of catridges, which are "only" I/O based, especially sound cards (OPL1-4 based, MP3) and more.
- Moonsound (the most powerful soundcard for an 8bit system ever)
- MP3MSX
- SE-ONE (MP3 and FM-Radio)
- Graphics9000
etc...

Today we were checking, which ports we could use. This adapter requires a full 256 port range (the MSX is using 8bit ports), but it can be splitted.
My idea was to use
CPC ports #FD60-#FDFF for MSX ports #60-#FF
CPC ports #FF40-#FF9F for MSX ports #00-#5F
This would cause nearly no conflict with any existing (popular/currently used) CPC hardware and would even be compatible with the upcoming V9990 graphic card from Tecnobytes.
Please tell me, if I missed something!
Title: Re: MSX-to-CPC I/O hardware adapter
Post by: rpalmer on 00:13, 16 September 17
Prodatron,

The problem with many CPC expansions is that they dont always check the full address bus to no be in conflict with any other expansions.
This means that any attempt to map CPC I/O to another systems I/O is likely to be problematic.
I would instead use an 8255, where Ports A, B and C connect to the MSX hardware and a single dedicated CPC I/O port control the 8255 (much like the internal one).

rpalmer
Title: Re: MSX-to-CPC I/O hardware adapter
Post by: Prodatron on 12:32, 16 September 17
Note sure, if I got you correctly.
This adapter will use ports #FD60-#FDFF and #FF40-#FF9F for MSX expansion hardware on the CPC.
If there is any additional CPC hardware connected, which is listening here, too, then yes, you have a problem. But as this range is still free in most cases, I don't see a big issue.
Title: Re: MSX-to-CPC I/O hardware adapter
Post by: GUNHED on 22:36, 17 September 17
CPC ports #FD60-#FDFF for MSX ports #60-#FF
CPC ports #FF40-#FF9F for MSX ports #00-#9F


You mean:
CPC ports #FD60-#FDFF for MSX ports #60-#FF
CPC ports #FF40-#FF9F for MSX ports #00-#5F
I guess. Well, then let's take a look at Moonsound.  :)
Title: Re: MSX-to-CPC I/O hardware adapter
Post by: Prodatron on 22:45, 17 September 17

You mean:
CPC ports #FD60-#FDFF for MSX ports #60-#FF
CPC ports #FF40-#FF9F for MSX ports #00-#5F
I guess. Well, then let's take a look at Moonsound.  :)
Yes, thanks for the hint!
The moonsound is something like the legendary "Gravis Ultrasound", but for an 8bit system (with "only" 24 instead of 32 digi channels). There is at least one open source multiple format + multiple hardware player for the MSX, which is supporting nearly all existing possible sound formats.
Title: Re: MSX-to-CPC I/O hardware adapter
Post by: GUNHED on 22:28, 18 September 17
WoW! Such an expansion adapter is a really great idea!  :)