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Chinon FB-354 Jumper Positions

clh333

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The two Chinon FB-354 floppy drives on my Amiga 2000 have six pins at the back between the data header and the power header. The one Chinon FB-354 on my 2500 has the same six pins but has a jumper in a different location:


A2000 both drives: A2500 single drive


o o o o o o

o --- --- o



I don't know what the difference signifies or whether it is important.

Each machine has the same 34-wire flat ribbon cable with the same twist.

Thanks for your replies.

-CH-

Pic:

FD800K.jpg
 
Found this bit of info on connection of floppy drives to A2000/3000/4000 (source: http://www.l8r.net/technical/t-floppydrives.shtml)

Amiga 2/3/4000's Regarding Their Internal Floppy Drives
For DF0: the device number must be set to DS0 on the drive and this must have the cable with the twist in it.. I beleive you peel out 4,5,6 and turn them around and put them back in.

For DF1: the drive number must be set to DS1 on the drive and this must have the section of cable that is not twisted.

If you have a DF1: in the machine you need to set these jumpers:

  • Amiga 2000 J301 must be on.
  • Amiga 3000D J351 must be shorted between 1-2.
  • Amiga 3000T J351 must be shorted between 1-2.
  • Amiga 4000:
DF1: ENABLE (J351) enable 2nd internal floppy (880 KB) as DF1: closed
DF1: ENABLE (J351) no 2nd internal floppy, or 1.76MB floppy as DF1: open​

And, disk drive pinouts internal and external: http://www.l8r.net/technical/t-diskdrive.shtml

Compatible drives list: mentions the jumpers on the back of FB-354s - 6-pin jumper block - Short pins 3 and 5.
(http://petersieg.bplaced.net/floppys/Amiga_Floppy_Teil_1.pdf)

Amiga 2010 3.5" Floppy Drive Installation Guide (1987) Commodore A2000
 
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Found this bit of info on connection of floppy drives to A2000/3000/4000 (source: http://www.l8r.net/technical/t-floppydrives.shtml)
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Thanks for your reply.

I've been occupied with restoring an IBM AT (a 5170 with problems of its own) the past few weeks but will return to the Amigas shortly. In the interim I recapped the Chinon FDDs and plan to replace the cable as well since the last one came apart in my hands as I was disconnecting it. Part of my problem is that with so many parts suspect it's hard to figure out which is at fault.

Thank you very much for this information.

-CH-
 
I have some FB-354 drives that are driving me nuts.

I know I tested them, back when they first came in and I know it was on a PC and I think I used a pin to card edge connector that was simple and just allowed for jumpering the DS position.

However, the damn things are hard-wired into DS0 and, even if you jumper DS1, it acts like DS0.

Has anyone managed to find the right traces to cut to get it to work as DS1 in a PC?

There is very little actually info (outside of various schemes on how to fit one in the early Amigas) on the FB-354, much less a schematic of the logic.

If anyone knows how to actually get it to work as DS1, I'd appreciate the assistance.
 
Found another post with info on 2 drive setup. The image mentioned in this thread was not found but the text posted may help:

Fester post #4 said:
Default Re: Jumper Settings For A2000 Floppies

leofoe said:
Although they are both Chinon FB-354 Rev.A drives, they've got different jumper blocks. Hope this gets you going.
Hi leofoe,

Thanks for the picture, this got me going. Essentially, the DF0 jumper stays the same as if there was only one internal floppy and DF1 jumper sits on the two right pins instead. The upper row of pins seen on the picture in one of the drives is not used at all.

As mentioned in the other response by Darrin, I also had to close jumper J301 on the motherboard. Page A-23 of the Amiga 2000 manual says this jumper has to be closed in order for the Amiga to recognize an ID bit stream from each floppy. This is normally not necessary when there's only one internal floppy. Found an extra jumper from a busted pc motherboard.

Everything works now. I let it boot normally from the hard drive first, then I inserted disks one by one in each floppy. After that, I shut down and inserted WB in DF0 and Extras in DF1 and re-booted.

All drives light up when fed. Everything worked just great.

Fester
More information was posted about cabling setup in later posts in this same thread.
 
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