Author
| external Z80B
|
monant
msx novice
Posts: 31 |  Posted: February 25 2007, 16:07 |
hallo,
I was tidying up my room this morning and I have come across an old
italian Magazine.( C16-MSX nr.38 year 1990)
There's an article wich talks about an Interface (developed by a Nederland Hardware House) to Speed up MSX2 to 7 Mhz.
Probably the reporter was too vague and I have not understood very well.
but ,Now, my questions are :
1) Pin description of Cartridge connectors shows that there are two
reserved line (Pin 5 , Pin 16 What are they for? )
2) There is no BUSAK and no BUSREQ , so how can exist two Z80.CPUs at the same time without conflict?
3) Are BUSAK and BUSREQ implemented on some MSX1/2 machine?
Thanks for your attention..
|
|
legacy
msx professional
Posts: 516 | Posted: February 25 2007, 17:35 |
I think that you are refer to a 7 mhz update kit, but this is not a cartridge.
More info at www.hansotten.com/msxdiy.html almost on the bottom of this page. |
|
monant
msx novice
Posts: 31 | Posted: February 25 2007, 22:17 |
thanks for replying,
Yes ,I have already visited this very interesting site many times
and I think the kit you 're talking about needs the Z80 on the motherboard and other components to be removed and replaced.....
the article I quoted above was not so detailed.....
Anyway , I'll take advantage of your patience
could anybody satisfy my curiosity about
answer 1,2,3 ?
 |
|
Edwin
msx professional
Posts: 594 | Posted: February 25 2007, 23:12 |
2) Because there actually can't.
(no hardware knowledge, so can't answer your other questions)
|
|
legacy
msx professional
Posts: 516 | Posted: February 25 2007, 23:24 |
Quote:
|
I think the kit you 're talking about needs the Z80 on the motherboard and other components to be removed and replaced.....
|
That's corrrect.
I did that update by myself, longtime ago, and it's still working great.
|
|
manuel
msx guru
Posts: 3381 | Posted: February 26 2007, 11:51 |
Z80B? Not Z80H?
|
|
msd
msx professional
Posts: 608 | Posted: February 26 2007, 18:34 |
In some old designs the z80b is used,but it really depends on the batch of z80bs if it can handle the 7.16Mhz. So this is ofcourse not recommended. Don't use the B type
|
|
monant
msx novice
Posts: 31 | Posted: February 26 2007, 20:50 |
my mistake (officially z80b is for 6MHz)
Z80H of course, but this is not the point , all my attention was focused on
questions 1,2,3 
|
|
manuel
msx guru
Posts: 3381 | Posted: February 27 2007, 12:52 |
|
|
AuroraMSX
msx master
Posts: 1231 | Posted: March 02 2007, 21:49 |
1) Pin description of Cartridge connectors shows that there are two
reserved line (Pin 5 , Pin 16 What are they for? )[/quote]Fill up space between pins 4 / 6, and 15 / 17, respectively ;P
They're not used, NC. Probably reserved for future extensions that never came to be.
Quote:
| 2) There is no BUSAK and no BUSREQ , so how can exist two Z80.CPUs at the same time without conflict?
|
Where did you get the idea of having 2 Z80's in one MSX machine? In the 7MHz project the old Z80 is replaced by the new one.
Quote:
| 3) Are BUSAK and BUSREQ implemented on some MSX1/2 machine?
|
Probably not. The MSX was not designed for a multi-processor environment. |
|
monant
msx novice
Posts: 31 | Posted: March 03 2007, 00:05 |
hallo,
Actually,Having 2 processor or a co-processor
was a wish more than a Idea ,
and it ' d have been nice a Z80 plug and play cartridge like FM-Pac for example . (in this PURELY HYPOTHETICAL case no skills wouldn't be required for soldering , replacing..risks of damaging our dear MSX )
but I know the argument is complex...
|
|
|
|
|
