MSX2 Philips VG-8235 - cable adapter for GOTEK DD

Rookie (19)

01-10-2022, 18:02

Hello,

a few days ago I purchased a Philips VG-8235/20 and thought "oh, I could easily swap the internal floppy disk drive with a GOTEK running flashfloppy"... Oddly enough, the cable connected to the FDD is different, and its only 1 pin row instead of 2.

- is it possible to BUY an adaptzer somewhere?
- if not, could anyone here please send me one?? (i live in germany)

Desperately asking
Oliver

Por Bastion Rebel

Expert (93)

02-10-2022, 08:35

Hello
have you changed the ROM DISK before otherwise the GOTEK will not work in DSK 720ko and if you do not tell it that you are in 360ko nothing will work, which adapter do you want I have an HE34 which transforms into HE14 but if the ROM DISK is original, nothing to do, and there are modifications to the motherboard to also do to be able to use the 720kb and the GOTEK I made some modifications on mine to the PC reader 720kb in A and GOTEK SLIM in B

see https://msxvillage.fr/forum/topic-4046+modif-vg8235-fdd720-g...

Por Briqunullus

Paladin (765)

02-10-2022, 10:27

A while back I bought an adapter board from Omega. Contact him, he may still have some. Ebsoft has them in their webshop as well, but they have been out of stock for ages.

You still need to modify your 8235 on the inside though. This has been documented by Repair-Bas on his website. Select diskdrives -> Inbouw 720 kB diskdrive in Philips VG 8235/20. He doesn't use any adapter board.

Most important part is replacing the system ROM. The original ROM only supports 360k disks. On the other hand, your Gotek doesn't support 360k images, unless you put a file ff.cfg on your flash drive and a line host=msx in it. Good luck!

Por plxbollo

Rookie (19)

02-10-2022, 10:42

Thanks so far for your tipps.

Im wondering if I got the right eprom here - As I saw, the VG-8235/20 seems to be more
compacted than the other model I have (8235/00) - smaller board, less chips...

Por Bastion Rebel

Expert (93)

02-10-2022, 11:27

I have the HE34/HE14 adapter and the ROMS but you have to see with a photo your ROM DISK if it is separated into 3 ROMs (bios/disk/ext) or if you only have one type 27C512 (64 kb ) or more ...
adaptator HE34/HE14

Por plxbollo

Rookie (19)

02-10-2022, 12:15

it seems to be the "one chip" version in this case... thats for the 8235/20.
The other one (8235/00) has 3 rom sockets and has already been modded (not by me)...

(what would you suggest? - which device should i keep?)

AND: is there a 2nd option, usiung the external FDD connector??

Por plxbollo

Rookie (19)

02-10-2022, 12:37

It shows this screen after start (MSX logo is fine):

Any idea what this could be?

Por Briqunullus

Paladin (765)

02-10-2022, 13:37

plxbollo wrote:

It shows this screen after start (MSX logo is fine):

Any idea what this could be?

Yeah, you can set your screen preferences. The good news is: the battery in your MSX works fine. Easy to fix.

WIDTH 80
COLOR 15,4,4
SET SCREEN

(you can use any width and color you like by the way)

Por Briqunullus

Paladin (765)

02-10-2022, 13:53

plxbollo wrote:

AND: is there a 2nd option, usiung the external FDD connector??

The external connector works fine, it even has the Side Select signal for 720k drives. So no need to modify the motherboard. In fact the modification makes the signals of the external connector available at the internal connector. An external drive can still be A:.

However, you'll need to power your Gotek externally and put it in some kind of housing. And you still need to replace the disk rom.

(Although last year it was claimed a 720k drive worked on the external connector, maybe you can give it a try first)

Por plxbollo

Rookie (19)

02-10-2022, 13:52

Yeah, Im still seacrhing the BIOS - feels like theres no end..

Oh and: where may I get an externalm cable?

The screen looked fine on a screenshot from the former owner, though.. anyway, will fix it after reasssemlbing the KB.
I already found an 27c512 eprom and erased it... I'M READY
(just need the 8245 bios...)

Por plxbollo

Rookie (19)

02-10-2022, 15:20

Found and assembled the whole 27c512 by myself, comparing the orig. VG-8235 and those 3 VG-8245 BIOS roms..
It seems to work now - I managed to boot from an external GOTEK drive.
Maybe I'll leave it like it is and only use the externbal drive - does that have any downsides?