At 14:26 29/03/99 +0200, you wrote:
At 13:19 24/03/99 +0100, you wrote:
MSX and DMA??? Seems quite impossible to me...
Isn't it?
Nope dudez, I've heard a lot about these possibilities, of MSX and
DMA... Of course, rebuilding the computer and peripherals. But I don't know
hardware
I would expect the hardware to use the busreq-pin on the z80. But is that
one actually in the cartridge-slot?
Unfortunatly, no, it isn't... :-(
It might be possible to add it to the MSX slot's, there are some reserved
pins.
However, just adding a wire from the ^BUSRQ signal to one of these pins
Hardware DMA indeed not possible with the builtin chips in the MSX.
But the term DMA stems from long ago (CP/M for eaxmple) when with DMA was
meant the memory location/buffer where the transferred data to/from is
stored.
That's not DMA, that's DTA... Disk Transfer Area.
~Grauw
MSX
On Thu, 25 Mar 1999, Ricardo Jurczyk Pinheiro wrote:
At 13:19 24/03/99 +0100, you wrote:
MSX and DMA??? Seems quite impossible to me...
Isn't it?
Nope dudez, I've heard a lot about these possibilities, of MSX and
DMA... Of course, rebuilding the computer and peripherals. But I
Holst [mailto:[EMAIL PROTECTED]]
Sent: maandag, maart 29, 1999 10:45 uur
To: [EMAIL PROTECTED]
Subject: Re: 64K VRAM?
Hardware DMA indeed not possible with the builtin chips in the MSX.
But the term DMA stems from long ago (CP/M for eaxmple) when with DMA was
meant the memory location/buffer where
At 13:19 24/03/99 +0100, you wrote:
The standard doesn't say anything about the method that the diskrom
should
use. So, it's just the case on many MSXs. The standard only says that the
interface should use memory addresses to transfer data between CPU and
FDC.
Ok, but this means that using
On Tue, 23 Mar 1999, Alex Wulms wrote:
] Ok, but this means that using DMA in page 1 is against MSX standard, or
] not?
I can say three things about accessing data in page 1:
1) It is no problem at all under MSX-DOS when you use address #0005 to access
the BDOS.
2) It might be a
For example, it's very useful for accessing the entire RAM using only the
#8000-#BFFF segment.
My MSX2 has 64kb of standard RAM and to access other pages I used to do
some LDIRs (i.e., I can handle that).
1. LDIRs are slow (OUT takes 11 ticks, LDIRing 16k takes, ummm, a LOT of
ticks)
2. If
For the most part of diskroms, DMA can be in page 1, because they
have
access to FDC through addresses 7FF8h-7FFCh and also BFF8h-BFFCh, and
they
transfer a small routine to F1BFh (or something like that) that
allows a
disk transfer to happen in page 1.
Is that MSX-standard or
]]
Sent: woensdag, maart 24, 1999 13:20 uur
To: [EMAIL PROTECTED]
Subject: Re: 64K VRAM?
For the most part of diskroms, DMA can be in page 1, because they
have
access to FDC through addresses 7FF8h-7FFCh and also BFF8h-BFFCh, and
they
transfer a small routine to F1BFh (or something like
On Wed, 24 Mar 1999, Hans Otten wrote:
Hardware DMA indeed not possible with the builtin chips in the MSX.
But the term DMA stems from long ago (CP/M for eaxmple) when with DMA was
meant the memory location/buffer where the transferred data to/from is
stored.
These days I use the
On Wed, 24 Mar 1999, Laurens Holst wrote:
MSX and DMA??? Seems quite impossible to me...
Isn't it?
Ehm... well, in the BDOS specs the term DMA-address is used for the start
address of disk-actions (read-write). This is NOT the same as DMA on
PC's...
Bye,
shevek
---
Visit the internet
[Using disk I/O on page 1 ($4000-$7FFF)]
2) It might be a problem when you are working under basic, using address
ªF37D to access the BDOS. Though, I'm not sure about that.
I am. I tried to load some data somewhere in page 1 using an ML routine
which was called from BASIC
On Mon, 22 Mar 1999, Marco Antonio Simon dal Poz wrote:
On Mon, 22 Mar 1999, shevek wrote:
On Mon, 22 Mar 1999, Marco Antonio Simon dal Poz wrote:
For the most part of diskroms, DMA can be in page 1, because they have
access to FDC through addresses 7FF8h-7FFCh and also
On Tue, 23 Mar 1999, shevek wrote:
On Mon, 22 Mar 1999, Marco Antonio Simon dal Poz wrote:
On Mon, 22 Mar 1999, shevek wrote:
On Mon, 22 Mar 1999, Marco Antonio Simon dal Poz wrote:
For the most part of diskroms, DMA can be in page 1, because they have
access to FDC
And does DOS2 work with 64kb of Memory Mapper?
No, DOS2 needs 128kB of Mapper. This is from the file environment.doc, that is
in dos2info.lzh, which can be downloaded from the FAQ:
When the DOS kernel is initialized it checks that there is the memory
mapper in the system, and that there
] The standard doesn't say anything about the method that the diskrom should
] use. So, it's just the case on many MSXs. The standard only says that the
] interface should use memory addresses to transfer data between CPU and
] FDC.
]
] Ok, but this means that using DMA in page 1 is against
On Fri, 19 Mar 1999, Laurens Holst wrote:
What if you want to load code (in Dos) from # using the BDos-routines???
Yup, right, you load it in #4000 and then switch it to #.
I never tried, but as far as I know the DMA can never be in page 1, since
that is where the disk-rom is switched
On Mon, 22 Mar 1999, Marco Antonio Simon dal Poz wrote:
For the most part of diskroms, DMA can be in page 1, because they have
access to FDC through addresses 7FF8h-7FFCh and also BFF8h-BFFCh, and they
transfer a small routine to F1BFh (or something like that) that allows a
disk transfer to
On Mon, 22 Mar 1999, shevek wrote:
On Mon, 22 Mar 1999, Marco Antonio Simon dal Poz wrote:
For the most part of diskroms, DMA can be in page 1, because they have
access to FDC through addresses 7FF8h-7FFCh and also BFF8h-BFFCh, and they
transfer a small routine to F1BFh (or something
On Thu, 18 Mar 1999, jam wrote:
Hi, Marco Antonio
Maybe you mean the NMS 8220?
That machine had only 64K RAM (normal memory mapper), but did still
have 128K VRAM, like every MSX2 I've ever seen...
MP
MP How can 64kb of RAM be memory mapper? Memory Mapper with only 4 memory
MP
On Fri, 19 Mar 1999, Laurens Holst wrote:
Maybe you mean the NMS 8220?
That machine had only 64K RAM (normal memory mapper), but did still
have 128K VRAM, like every MSX2 I've ever seen...
How can 64kb of RAM be memory mapper? Memory Mapper with only 4 memory
blocks is a bit unuseful!
Maybe you mean the NMS 8220?
That machine had only 64K RAM (normal memory mapper), but did still
have 128K VRAM, like every MSX2 I've ever seen...
How can 64kb of RAM be memory mapper? Memory Mapper with only 4 memory
blocks is a bit unuseful!
NOT!!! With a non-memorymapped 64k RAM the
But the main utility of the Memory Mapper is to create a block switching
system that allows the slot to contain much more than 64kb of RAM. Using
Memory Mapper only to exchange memory contents isn't a big deal, because
you still can do it using LDIR (or using a famous technique called swap,
like
On Thu, 18 Mar 1999, shevek wrote:
On Wed, 17 Mar 1999, Marco Antonio Simon dal Poz wrote:
How can 64kb of RAM be memory mapper? Memory Mapper with only 4 memory
blocks is a bit unuseful!
Not at all. With a mapper every 16kB page can be switched on , 4000,
8000 or C000. This is
On Thu, 18 Mar 1999, Marco Antonio Simon dal Poz wrote:
Is there a program that takes profit of the 64kb memory mapped?
There once was a basic-database that used the mapper. I guess it worked
with 64kB as well... Most flexible memory programs do, I think. The memman
filecopier BK does... I
On Wed, 17 Mar 1999, Alwin Henseler wrote:
Mitsubish ML-G1 had 64K VRAM, I think.
Philips has one also, I don't exactly know which type it was, but they
did have one. And it was not the 8280 :-) (nor was it the 8235, because
I had that one, nor the 8245 and 50, so it must have been
On Wed, 17 Mar 1999, Marco Antonio Simon dal Poz wrote:
How can 64kb of RAM be memory mapper? Memory Mapper with only 4 memory
blocks is a bit unuseful!
Not at all. With a mapper every 16kB page can be switched on , 4000,
8000 or C000. This is useful for example when you want to use a lot
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