FC9801 computer FDD replacement

clingel
Posts: 13
Joined: Wed Aug 15, 2012 2:21 am

Re: FC9801 computer FDD replacement

Post by clingel » Wed Aug 22, 2012 1:25 am

And in the case of the Hxc firmware you know exactly where the clock is so there is nothing missing you can just generate the clock in the loop that encodes the mfm or fm data stream.

Jeff
Site Admin
Posts: 6649
Joined: Fri Oct 20, 2006 12:12 am
Location: Paris
Contact:

Re: FC9801 computer FDD replacement

Post by Jeff » Wed Aug 22, 2012 7:51 am

clingel wrote:And in the case of the Hxc firmware you know exactly where the clock is so there is nothing missing you can just generate the clock in the loop that encodes the mfm or fm data stream.
No. There are only a stream for the HxC. It doesn't "understand" what it stream.
There are no loop encoding mfm or fm into the firmware, just a data streamer from the sdcard:

http://hxc2001.free.fr/floppy_drive_emu ... format.pdf

A new hardware is currently designed with an FPGA. This one integrate the VFO/Data separator.

But for the moment you need the external VFO with the actual hardware.

EDIT : Anyway thanks a lot for this document : the page 18 seems to show an Data separator schemactic without any specialized circuit. Very interesting.

clingel
Posts: 13
Joined: Wed Aug 15, 2012 2:21 am

Re: FC9801 computer FDD replacement

Post by clingel » Sat Jan 26, 2013 1:54 am

Jeff, Is the FPLA version of the floppy emulator with the data separator still in the works? My machinist friend has finally decided to go ahead with his conversion. I built a data separator from a single AtTiny that decodes an actual floppy stream so it will also work with the emulator, but if you have a version with the separator built in it saves me from building and installing one in his CNC machine.

-Charles

WishIhadaMits
Posts: 1
Joined: Fri Dec 07, 2018 3:53 pm

Re: FC9801 computer FDD replacement

Post by WishIhadaMits » Fri Dec 07, 2018 4:22 pm

Hey there - I came to this thread after searching all over the net for info on how to get my old Japax wire EDM going. One drive has seemed to die completely, and the machine won't boot unless it can read both drives at the same time. I swapped the drives in the PC-9831 enclosure along with the jumpers, but no luck. My disk drives are FD1135D.

There is only one place in US that still services these machines, and if you own one then you already know who they are. We bought our current "refurb" floppy unit from them about a year ago for $1300 and it's already on the blink. That was after we tried two of their previous units with no luck. And of course, their warranty is only for 90 days. :evil: They'd be more than happy to sell us another complete unit, or one with newer drives for $1600, or their very latest innovation - the USB adapter model for a mere $2,000.

I do not want to give these people any more money, but my knowledge of old hardware and programming is dismal compared to the members here. If all I could do is find a way to swap a newer-style floppy disc drive into this enclosure I'd be happy, but a USB adapter would be fabulous.

I've read this entire thread several times and just feel rather overwhelmed. If anyone here has successfully completed a Japax EDM conversion I'd love some guidance. I'd be happy to chat over the phone as well if someone would be so inclined. This company is just bending us over at every turn and I'd love to fix this machine completely without their help. Thanks for reading.

Jeff
Site Admin
Posts: 6649
Joined: Fri Oct 20, 2006 12:12 am
Location: Paris
Contact:

Re: FC9801 computer FDD replacement

Post by Jeff » Fri Dec 07, 2018 9:47 pm

The HxC Floppy Emulator was tested on these machines, but you probably need the additional board to generate the missing VFO signal. These boards was made several years ago and are now sold out. i will ask Lotharek if he still has some units.

skippysmt
Posts: 7
Joined: Thu Aug 02, 2018 11:11 pm

Re: FC9801 computer FDD replacement

Post by skippysmt » Thu Jan 17, 2019 10:49 pm

I have done 2 machine now in the UK you need to buy a board from kitahei88 in Japan first of all and the SD reader. Around 80 to 90 pounds for this board
The hardest part was to copy the disk .Jeff just help me with the last one I did after I copied it using kryoflux as I had a speed issue when converting them back. I did not know about a file I had to attached to the back up call rpm300rpm360 to change the speeds once done it was very easy.
I can take a photo of the pin setting on my Elvy Japax. I have been using mine at home now for 4 years without fault.

Post Reply