Warning, long photo history: A MSX2, Sony HB F700 start after 12 years.

lostrego

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AmiBayer
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Hi all:

While clearing some old stuff from my parents' house, today was the turn for this little 8 bit gem.

What we have here is a Sony HB F700 MSX2 computer that was in some form one of the top of the line of Sony MSX 2 systems way back in the late eighties.

Unlike the majority of the MSX line that where all in one computers (keyboard and CPU) this one had a more professional looking setup with separate keyboard and a built in 3,5 inch DD floppy drive.

Some specs of this machine are :

CPU: Z80 running at 3,6 Mhz
RAM: 256KB RAM
Video Ram: 128KB

Its graphic abilities where on par to the rest of the MSX2 standard:max 256 colors on screen from a palette of 512 and resolutions up to 512×212 pixels.

Sound is provided by a Yamaha YM2149 3 voice programmable sound generator chip.

It starts directly to MSX basic but an OS existed also for these, it was the MSX DOS, that was in fact much like a 8 bit variant of some ancient version of the MS-DOS for 16bit PCs.

So lets go on, here it is, sat almost 12 years or so on a shelve collecting dust and gunk:


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And its back:

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Disk drive is absent as it was already faulty when it was given to me, back in those years I used an Amiga Chinon drive to work with it as this machines use the very same kind of drives as the amiga does (RDY signal enabled ones).



Here it is the original Disk drive:

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Well so lets set it up, plug it to a TV and switch it on to see what happens: magic blue smoke ? , fireworks? , maybe the house's circuit breaker going nuts?


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Nah, it started like a Champ :D:

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Then the basic:

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Note that this machine gives only B/W picture if the composite video output is used (maybe it does use NTSC color encoding?), for color an RGB to Scart cable is needed but I can't remember where it is, so only B/W fun this time.

Now lets try some random cartridge game:

Here it is, the mighty Konami's Nemesis 3, wit looooads of gunk on the connector so yup, it failed the first time. :LOL:
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After some cotton stab and alcohol cleaning here it goes:

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Then some old school fun:


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Well, there are lots of TLC to do to this machine, first of all this model have a battery backed RTC to store date on files while using the MSX-DOS, so considering It's a 1986 machine high are the chances that the battery is one of those Ni-Cd time bombs :(, I have to check ASAP.

So that's all for this time, hope you enjoyed this. :)

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amazing!
keep us posted with more pics , especially when you open the machine!
How is the scrolling on it? super smooth?
 
Thanks

I have to bring it to my home, maybe next week, and then I'll check it inside and do some more pics, for what I can remember the mobos (yes, there were two boards, one on the upper an other on the lower side :eek:) were mainly based on that eighties cheap (but effective) Sony's kind of doing circuit boards, with wire bridges instead of printed tracks on the board, in fact its internals resembled more an eighties Hi Fi Amp. than a computer. :LOL:

And yep smooth scrolling and awesome graphics for an 8 bit system, In fact talking about 8 bit games I'd say that the MSX was one of the best systems of that era when talking about graphics.

INMO they are miles away from the graphics of other Z80 systems like the speccy or the CPC but don't tell it loud. :shhh:.

:)
 
Looking forward to the tear down, cleanup, retrobrite and re-build (if that is what your going to do)

It looks surpringly modern imho! Sony should take a good look at their past designs as this would have been ok for the PS4 lol!
 
@ElectroBlaster:

My plans for it at the moment are striping it down and give it a good cleanup, I'll have also to locate a working FDD drive, any Amiga compatible one should do the trick ok, so I'll probably have a look for a new one on Amigakit or Vesalia.

Thankfully It's in overall good shape with no rust at all on the case and chassis and only dust on the empty floppy drive bay.

I have to locate the keyboard that was stored on a box somewhere an the Din to Scart RGB cable (that was faulty the last time I used it, probably a broken or bad solder given it symptoms, so another thing to fix).

Ah and of course the MSX DOS disks and some games and apps that have on floppies that are mixed with a bunch of amiga disks. :picard

Retrobrighting it is not my priority ATM as I'll have to do it to some other items first.

And yes many Sony devices from late eighties look very modern for their time.
 
Finally I've opened it and had a quick cleanup of it.

Not much time left to mess with it those days so I've done only a quick vacuum cleaner clean.

First this was its internals once opened:


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Just as expected loads of dust as I never cleaned it, I've got that machine around 1999 or so and the only times that I've opened it was to put a provisional replacement floppy drive.

You can note here what I was talking about on previous posts, The motherboard are in fact two boards, also you can note that peculiar way of doing circuit boards that Sony had that times:

Printed circuit only on one side of the board and lots of wire bridges on the other side (the visible part here) and bus cables.

Don't know what was the reason of doing this that way as in those times (1986) two layer PCB's were yet quite common (as the one of the A500 mobo.) maybe costs, Note that I've seen this very same way of doing PCBs on many other Sony devices of that era (mainly HiFi equipment), that could be reasonable as HiFi gear is not as complex as a computer, but using it for computers (and yes an 8 bit computer but a quite advanced and complex one) seems quite odd.

Well here is the Yamaha V9938,the graphics chip:

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This is an evolution of the Texas Instruments TMS9918 found on several old 8 bits computers as the MSX1 range of computers, the ColecoVision and the Ti-99/4A among others.

This Yamaha chip have text modes of 80 x 24, 40 x 24 and 32 x 24 columns.

Graphics resolutions of: 512 x 212 (16 colours from 512), 256 x 212 (16 colours from 512) and 256 x 212 (256 fixed colours)

Supports 32 hardware sprites with 16 colours, and max of 8 sprites per horizontal line.


Here it's the power supply, note that passive heat dissipator that seems borrowed from an HiFi amp:

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And finally the mother of all troubles: the RTC battery! :wooha: :

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Look at that old NI-Cd bas**rd! , surprisingly enough it's in not so bad shape, not that bad considering that this MSX was made around 1986/87, I feel that I was very lucky this time and only a bit of sulphate is seen on one of its sides, not even any visible or evident circuit damage. :eek:

It was in that so good shape that even didn't mess with taking it apart (yet), but calm, It's on the must do list. ;)

Well I was a bit short of spare time this evening and finally I've done only a quick vacuum clean of it, here it's:

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Well that's all for today, I'm a bit tired now and such effort and the high temperatures this days here deserve a big fresh :pint::pint:


See you!
 
Nice pictures and computer! :)

I think there are two boards because the top one appears to consist mostly video/audio circuitry. My Philips NMS-8250 is the same. Both Sony and Philips had top models that had superimposers. Two board solution enables you to swap only the video part, while keeping the rest in tact. A sort of graphics card so to speak.
 
Great post. I have a similar machine. I used to have also a Philips NMS8255 and later on a Philips NMS 8280. But both Philips are sold. I only have this HB-F700P left. I opened it up also and removed the upper print, here you see the lower print:


IMG_6382small.jpg


The big chip on the bottom left is the Z80A. The main processor of the MSX.


Since I read this thread, I took out also the NiCd battery. I am planning to replace it with a version I found on Ebay.

2014-05-22 11_11_43-2 x Ni MH 80mAh 2 4V Button Rechargeable Battery w Tab _ eBay.jpg

Although my battery was also optical still in good shape (it did not work anymore however, not holding any charge):

IMG_6371NiCd.jpg
Let's see where my project with this machine ends.
 
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So, I got my battery! It is the same size as the original one, so putting it in was easy:

BatteryOldAndNew.jpgNewBatteryInPlace.jpg
After this my MSX again remembers date and time, in basic
get time A$
print A$
get date A$
print A$

And to start up with 80 columns:
width 80
set screen

I also replaced the drive with a PC floppy drive. I first modified the drive, but then I found out, because of the print on the connector to the MSX drive, I cannot build in the drive. The connector on the PC floppy drive is upside down compared to the MSX one. So the connector with print won't fit in case the drive is build in.
So I made a nice extension cable, which allows me to directly use a PC floppy drive in my MSX without any drive modifications:

Join PIN33 (GND) with PIN34 (READY). Default pin34 on PC is 'Disk Change', connecting it to ground makes it always 'READY'
Conect PIN10 from Msx main board cable to PIN12 on floppy Pc Drive (to make it work as drive A in stead of B)

This is the end result without tape:

FloppyDriverConverter2.jpgDriveconnectorOpen.jpg

And finally with some tape, so I do not get any short circuits:

DriveConnectorTape.jpg
 
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Very well done!
 
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Hi, after all these years I want to thank you, I now have a Sony HB F700D and unfortunately no RGB cable (ordered). I was already amazed by the black and white picture of the AV output, and that with the battery is also very interesting. My floppy drive went immediately, but I will clean it anyway.
Thanks for the info guys.
mfg IRON
 
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