[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: Looking for MSX2 expertise
- To: "'General Discussion: On-Topic and Off-Topic Posts'" <cct...@classiccmp.org>
- Subject: RE: Looking for MSX2 expertise
- From: "Andrew Lynch" <LYN...@YAHOO.COM>
- Date: Mon, 5 Aug 2013 21:04:03 -0400
- Authentication-results: gmr-mx.google.com; spf=pass (google.com: best guess record for domain of LYN...@yahoo.com designates 220.127.116.11 as permitted sender) smtp.mail=LYN...@yahoo.com
- Cc: <n8vem...@googlegroups.com>
- In-reply-to: <1A89ECB31B7D4B329245B052C69200A4@tababook>
- References: <000301ce9162$69e5e660$3db1b320$@YAHOO.COM> <B39B276C5D9241D09C8D1A5FCE740BEA@tababook> <000c01ce9170$929eac00$b7dc0400$@YAHOO.COM> <1A89ECB31B7D4B329245B052C69200A4@tababook>
- Thread-index: AQK1F+g2ZgrhKwzamWHUsE7AXUld9QG7IarlAXqkRR4A6Wft3JeZVWnA
> -----Original Message-----
> From: cctalk-...@classiccmp.org [mailto:cctalk-
> bou...@classiccmp.org] On Behalf Of Alexandre Souza
> Sent: Monday, August 05, 2013 7:59 PM
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: Looking for MSX2 expertise
> > Honestly, I don't know much of anything about MSX.
> You should! This is a **very nice** computer for mostly anything.
> I'd reccomend you to take a look at something if you have time:
> - BlueMSX emulator and its source code
> - MSX Datapack (3 huge books in japanese, but some info and schematics
> well detailed in English)
> - MSX Techinical Handbook (you can find an excellent scanned copy at
> > Assuming we start with this as our baseline configuration 1. N8VEM 8
> > slot active termination S-100 backplane 2. S100computers.com and
> > N8VEM S-100 Z80 CPU board 3. S100computers.com and N8VEM S-100 VDP
> > Are any changes necessary to the above boards to provide MSX and/or
> > MSX2 compatibility?
> I need to study the schematic of the boards. I'm travelling for work
> now. I'll download them and take a look.
> > What else would be necessary to complete MSX and/or MSX2
> > compatibility? I assume some sort of S-100 board with 64K SRAM + IO.
> > Probably a cartridge port, couple 8255 PPIs for control and ASCII
> > keyboard and a serial port for a mouse? Is there any sort of
> > interrupt controller or DMA controller?
> The MSX is way simpler than that. Basically (for MSX1 compatibility)
> - A Z80 processor clocked at 3.579545MHz
> - A AY-3-8910 chip (sound processor, but also used for cassete input
> - A 8255 PPI
> - A TMS9128 (or compatible - you can use 9938 or 9958 processors since
> they are a superset of the 9128) video processor chip
> - At least 16K of RAM (preferably 64K)
> - A little of glue logic :o)
> Everything else is an expansion and MUST be glued to the expansion
> > We can reuse the S-100 bus interface "glue" from other boards. What I
> > am looking for is the components necessary for hardware compatibility.
> Maybe, but what is the objective of the project?
> - Create a MSX?
> - Create an add-on board for MSX compatibility to an S-100 computer?
> - Creating something new? :D
> Greetings from Brazil :)
Hi Alexandre! Thanks! There are two objectives for the project
Primary objective: To supply the necessary hardware to complete MSX
compatibility at the hardware level on an S-100 bus system. I believe this
would be a first.
Secondary objective: a small general purpose SRAM and IO board to help with
debugging a simple system when paired with only a CPU board.
From what I read above it sounds like there needs to be a clock signal tie
in from the V9938 VDP to the Z80 CPU clock to supply the 3.579545 MHz
signal. It is emitted from the V9938 if I recall correctly. I am thinking
an "over the top" style wire jumper with the Z80 CPU board next to the VDP
on the S-100 bus.
Also the ongoing design of the S-100 VDP V3 may need to be modified for
cassette IO functions. How are those implemented? There are spare GPIO
pins on the AY-3-8910 so it makes sense if we are talking about motor
control, Push to Talk, etc.
A simple 64K SRAM + IO (8255 PPI + UART) would be perfect for not just MSX
compatibility but for builders in general as a CPU board debugging tool.
Thanks and have a nice day!