Hello, MSXers.
There were lots of discussion. I'm happy with many mails :) although
someones may not like. I sumarize my thought. And I want to focus
on the new MSX hardware from now.
1. Why spend times on developing new MSX?
I WANT to spend my times on all for MSX. It's all. Logical answer is
impossible. Can "Money" be a logical answer? No. Why money?
Also I cannot understand why do you spend your times on developing
MSX sofwares/emulators even on writing e-mails to MSX mailing list.
Another point: Making an emulator requires more time, efforts than
making a hardware. The ONLY problem is that I have no money.
Anyway, use/develop emulators if you want. Or if you want/make
hardwares, let's discuss!
2. Why Standard?
Make a chance that we buy old MSX chips. These chips are needed for
keeping the compatibility.
Someone wrote that those chips are not produced anymore while
someone wrote that those chips are under productions yet! I bought
V9958s 6 months ago, and I heard from the seller that Yamaha produced
V9958 but not much. I don't know if I sould give up those chips or
not...
Egor said that we can use PGA for such chips. That's right. I'm
currently working on make a graphics accelerator with Altera Flex8000s.
Coding and simulation are easy. I just worry about the cost.
In the case of PGA that I used, it costs $1000/chip. I don't know the
cost of 7000 series. Egor, can you expect the cost when you use PGAs
for VDP, PSG, MSX-MUSIC?
3. I'm currently working on Z180 expansion board.
I will use :
- Z80180 (10MHz)
- PPI(8255) x 2
- 32KB ROM
- 128KB SRAM
- Several TTLs
The cost is about $30 without PCB(about $300 :().
It has following main functionalities:
- Two serial ports
- One parallel port
- One keyboard interface
4. Plan for new MSX
- CPU: Z180 or Z380 (more available chip will be chosen)
- VDP: V9958 (I hope that it is under production yet...)
- FM : YM2413
- PSG: YM2149
- PPI: i8255
- Memory: Lower 64KB space is same as current MSX.
- I/O: When Z180 used, lower space(00h-3Fh) is used for internal registers.
That's all. I don't want to add new features such as IDE, PCI, OPL4 and
so on. They should be supported by external cartridges which is the MSX
concept.
I have currently Z180, Z380, V9958. Other chips are easy to buy except
YM2413 and YM2149 which I'm seeking yet. The cost will be below $100
without PCB. If I can, it's cheap, realistic and compatible with MSX.
Just it is a faster MSX2+ which has more memory space.
- Jun.
