Monday, June 27, 2016

Victor Video Titler JX-T500

Let's continue our MSX and video production series. We already saw that the MSX2 had a video processor with nice A/V resources and it was not uncommon use it to create openings, scene transitions, subtitles, etc. Then, we showed two video titlers from Sony and one from Panasonic.

Besides Sony and Panasonic, other companies did MSXs with A/V features: Pioneer, Philips and Victor. Even without being present in Wikipedia's list, there is a good chance that those companies did some A/V equipment using MSX technology.

Victor/JVC advertising from MSX Magazine 1987-04

AFAIK, the MSX community did have some "inside sources" in Philips, so I guess that if this kind of equipment existed, it would be already known to us. But who knows? Maybe, sometime, we still can find a "hidden" MSX from Philips.

Pioneer is a promising source, the UC-V102 shows that the company continued the relationship with MSX after their two MSX1 models (PX-V60 and PX-7). However I didn't saw any video titler or digitizer from Pioneer. Maybe a better research could change this situation, but, by now, we know nothing. Our last hope is in appliances from Victor.

And Victor had many video equipment in the 80s and 90s. And some of this equipment looked very good to the purpose of this blog. So, let's try one of those machines.

Victor Video Titler Model JX-T500
The 日本ビクター株式会社 means "Japan Victor Company" (JVC)

Victor JX-T500

The Victor JX-T500 have a good design. The highlight is the drawing surface at center. At top we have many "touch" functions as the keyboard, color selector and the many drawing tools. The tablet and the functions at top are operated using a ugly stylus (which I have and don't know where it is now to be pictured). At both sides the video titler have other controls, as the video transitions and the fade selectors.

A good look of Victor JX-T500

The color selector, some drawing tools and a partial view of the keyboard.

The color selector is a 4x4 grid with 15 colors and, in the last spot, the option to "create" your own color with RGB values.

In the rear of this unit the audio and video inputs and outputs and the power cord.

And what's inside JX-T500?

The JX-T500 have, at least, five circuit boards. In the the top half we can see two holding the side controls and the one that handles the drawing board and the other "touch" controls. The bottom half have the power supply, the digital board and the video board. Those boards are connected by a lot of wires.

I hate when we have to disconnect a lot of wires

But we can see a familiar IC in the digital board

Here we can see the power supply, the video board and the digital board.

After disconnecting a dozen of these wires, we can have a clear view of the circuit boards in the bottom half of JX-T500. The digital board is very clean, we can see a Mask ROM, an empty IC slot, the Yamaha V9958 and some VRAMs.

Close view of JX-T500's digital board.
At top left we have a buzzer, then a Mask ROM and,
at right, the Yamaha V9958 and the VRAMs

The Yamaha video chip, and... 192KB of VRAM!?!?

Some VRAMs? No, a lot of VRAM. The V9958 is connected to 192KB of VRAM. While the VDP supports this amount of VRAM natively, it is a bit tricky the use of this additional VRAM in some MSX video modes. But it can be used to store additional pages on some screen modes.

As we said in the posts about Panasonic VW-KT300, to have the same chips of a MSX computer didn't means the machine follows the MSX architecture. We need to investigate a bit more. And there was more ICs on the other side of digital board that we want to see.
The other side of JX-T500's digital board

The first IC that we see is a Fujitsu MB621974, a gate-array. Nice! This can be the MSX-Engine of this video titler.

Fujitsu MB621974 gate-array

At center of digital board, there is two RAM chips from Mitsubishi, which totals 64KB of RAM.

2 x Mitsubishi M5M5255BFP

Ok. By now JX-T500 have a MaskROM, one MSX2+ video processor, 192KB of VRAM, a gate-array, 64KB of RAM. To have all required components to be a MSX, we need that this gate-array is a MSX-Engine equivalent and a Z80 compatible processor. Then...

Motorola MC68HC11

OUCH! How this can be? The main processor inside of JX-T500 isn't a Z80 compatible, but a 6800 compatible. This is a huge disappointment. After that, I lost the interest in this appliance, so I didn't dumped the Mask ROM contents of JX-T500, and tagged this appliance as a "Not MSX". We were so close... : (

More luck next time.

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