|National FS-5500's advertising in MSX Magazine 1986-01, |
it's an amazing machine with AV capabilities, one or
two floppy disk drives and a trackball integrated in
keyboard. The downside is the amount of RAM, only 64KB.
Like Sony did before, Panasonic used their know-how in MSX and Video applications to build their own videotitler: The VW-KT300. This equipment is not totally unknown by MSX users; it had a full-page article on the MSX Magazine (but without the word "MSX" in the text):
|First section of the article on news from Panasonic in |
MSX Magazine 1990-03. As you can see, no "MSX" in this section
And, in an other article from 1990, the VW-KT300 is already identified as based on MSX technology:
|Panasonic VW-KT300 in MSX Magazine 1990-04.|
The same article lists Sony XV-J770 as MSX based.
It's no surprise that this Panasonic appliance is in Wikipedia's list of MSX based hardware (The text in red says "VW-KT300 from Matsushita Electric Industrial"):
"特にビデオタイトラーでは、ソニーのXV-J550/J770/T55Fシリーズや松下電器産業のVW-KT300などの家庭用タイトラーのハードウェ ア構成は明らかにMSXを応用・流用したものである。ただし、これらの機種では基本はMSXシステムをベースとしていても独自の実装がなされており、特に BIOSなどは大幅に簡略化されMSXとしての機能は望めないなど、簡単な加工程度では汎用のMSXシステムとして使うことは不可能である。"
With that information, and some news and forums posts about XV-T550, I bought this machine, with the hope to easily boot it in MSX mode. The VW-KT300 was the first equipment that I bought in my search for hidden MSXs. It was not featured in the first post in this blog because:
- Other machines (Aucnet NIA-2001 and Pioneer UC-V102) have a lot more impact and
- The story of how I found this VW-KT300 is very boring: "I saw the name of this machine in an article in Wikipedia, I bid on an auction and won."
But, even without meeting all my expectations, the machine is very interesting!
From outside it have a good design; with some inputs and outputs for video and sound, an IC card slot, a custom keyboard and a mouse.
|Panasonic VW-KT300: a very clean visual in front panel, |
polluted by a big colorful sticker.
|Rear of VW-KT300, with many S-VIDEO and RCA connectors|
The mouse is the Panasonic FS-JM1, the same that are sold for MSX computers:
|The VW-KT300 mouse. The only place where you can see the MSX |
logo without open the appliance.
All videotitler functions, besides the point and click, can be controlled using the small keyboard:
|The control keyboard|
(image from a Y!J auction. I'll change it when I (hopefully)
find where is my own keyboard)
In the front panel, we have the power button, the keyboard and mouse connectors, the IC card slot and S-video and RCA inputs. It seems that the IC cards were a common media for appliances in Japan:
|As said in main text, the front panel have a power button, |
power LED, keyboard and mouse connectors and IC card slot
|Input-1 connectors: S-VIDEO and RCA. Next the selector |
for Black&White or Color output
|The two sets of Output connectors. Both with S-Video and RCA|
|The knob to adjust the superimposer hue, then a power |
outlet and the power cable connector
What is inside Panasonic VW-KT300?
When I opened the VW-KT300, I already did saw a few pictures of the mainboard on this site (in japanese) and knew that the cartridge slot was not there. But still thought that would be a MSX engine somewhere at PCB's other side and a full MSX BIOS would be waiting for me. However, as I said before, I am not a good guesser.
|Half of the logic board. At top center, the NEC gate array;|
at top right you can see a Z80B from Zilog.
The bottom row are the ROMs
|The other half of logic board. At top left the VRAMs; |
at picture's center, a CR2032 battery and an Yamaha V9958
(the chip with the heat sink). At bottom row we can see
more RAMs and the ROMs.
Talking about the good stuff: the machine has an Yamaha V9958 with 128KB VRAM, a Z80B (faster than usual) as main processor, 64KB RAM and many Kanji-ROMs from Panasonic's MSX equipment (computers, cartridges, printers, etc).
|After an empty IC placement there are two ROMs. The first |
one is from FS-PK1 printer and the other one looks to be
the Kanji-Font of the A1FX MSX computer.
Excluding the RAMs and ROMs, the main ICs inside the VW-KT300 are:
- Zilog Z0840006PSC: Z80 processor with 6.17Mhz clock
- NEC D65042GD405: NEC gate array
- Yamaha V9958: MSX2+ VDP
As we can see, no stock MSX engine in this list. But we know many MSX computers that doesn't have a engine from Yamaha or Toshiba, those machines have discrete components or a custom gate array to do the MSX engine's job, the big NEC gate array is a good candidate to fill this role.
|The NEC gate array|
I took this device to Alexandre Tabajara's lab, so we can take a better look in this NEC IC and dump the program ROM. But that is a talk for our next post.