NMS8280 problems | MSX Resource Center (Page 2/3)

By luppie

Paladin (864)

23-02-2014, 22:10

Maybe, the drivebracket is making a short circuit when placing it horizontal.

By Gregory

Master (197)

23-02-2014, 22:44

I'll take another look at it tomorrow, but I see no damaged wires...

By AuroraMSX

Paragon (1902)

24-02-2014, 11:54

Try disconnecting the drives and starting the computer without them. I suspect (one of) the drive(s) got some internal injuries :-S

By Gregory

Master (197)

24-02-2014, 18:06

I tried that. If all goes well it takes about 24 seconds before i get the basic screen and if it doesn't i just get a blue screen.
Maybe i'll give it a try with other FDD's (if i can find some).

By Jipe

Paragon (1549)

24-02-2014, 18:41

try with the other disk rom , just push the switch connect on IC117 before powered MSX

By Gregory

Master (197)

25-02-2014, 00:08

Jipe wrote:

try with the other disk rom , just push the switch connect on IC117 before powered MSX

I took another look at the switch on the frontpanel (the one's that is broken) and it occured to me that pin 27 (A14), might be floating. So I put A14 to ground and I also tried putting A14 to VCC.
In both cases i get the normal startup procedure (except for FDD B that gives 'disk offline' even when a floppy is inserted).
So maybe FDD B is broken.

So I think we are on the right track here and i believe that the problem occured because A14 was floating.
Still don't understand what the purpose of that switch could be since i get exactly the same thing on startup.

By AxelF

Champion (395)

25-02-2014, 00:39

Maybe you could take some pictures of the switch and everything attached to it,
so we can find out what it exactly does.

By Gregory

Master (197)

25-02-2014, 08:21

AxelF wrote:

Maybe you could take some pictures of the switch and everything attached to it,
so we can find out what it exactly does.

I will do that soon.

By bakoulis

Master (166)

25-02-2014, 11:34

About the FDD B, probably needs a new belt. Is something common for this old disk drives. Is an easy fix, if you buy a new belt from somewhere. About the broken buttons and sliders to the front face, is the first thing that I had wrote you to pay attention. Remove the suspect button's cables and try to work with single jumpers instead.

By Daemos

Paragon (1959)

25-02-2014, 12:44

Quote:

About the FDD B, probably needs a new belt.

nms82xx drives have direct drive. No belt in there