Small cheap tip to VG8235 owners

By bennyroger

Expert (74)

bennyroger's picture

11-05-2007, 23:26

Do you own a Philips VG8235/20 with only a single sided drive?
Don't to want to change the disk bios and replace the internal FDD?

Connect a normal FDD cable to the external port, cut wires 33 and 34 on the cable and connect them together.
Find any PC disk drive and supply power to it from either a PC power or one of these new fancy powersupplys you can buy these days for 10euros.
Power on the system! Drive B: you just connected will act as a 720kb diskdrive, you do not need to change the bios. It will format, read and write to 720kb disks. If you boot with MSX-DOS from drive a: go to drive b: and type basic, 720kb disks that starts from basic will now run from this drive.

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By nikodr

Paladin (721)

nikodr's picture

11-05-2007, 23:43

Cool!I have exactly this Philips VG8235/20
One question:If it does not have the disk bios how is it possible?Why is this happening?

By bennyroger

Expert (74)

bennyroger's picture

11-05-2007, 23:52

Don't know why exactly, but my guess is that the standard chip blocks the internal connector from using 720kb, while the external is not. Have tested this on 3 different VG8235 machines and it work on all of them.

By Poltergeist

Champion (266)

Poltergeist's picture

12-05-2007, 00:25

It works this way. On my VG8235 (and I do even believe it was a 00) the internal drive was removed, replaced by a PC drive, which was connected to the external driveconnector.

By mohai

Paladin (741)

mohai's picture

04-06-2007, 21:38

This is because BIOS only works with single side disks on the A drive.
I ahve used a similar trick for year on my 8235/00. If you use poke -609,201 to force the drive to no t stop, you will be able to work with double-sided disk too Smile
A BIOS change is needed, anyway

By fubukimaru

Rookie (26)

fubukimaru's picture

25-06-2018, 15:06

Does this trick work with vg-8230 for the external FDD?

By abnog

Supporter (4)

abnog's picture

05-12-2018, 21:55

I tried this on my VG8235/20 with a couple PC FDD drives. Strangely enough, the connections on both drives were reversed, i.e.: the red side of the cable was on the 34 pin side. Had to cut the plastic connector to make it fit. It seems to work (the led on the drives turns on syncronously with the computer) but when I try to "_format" the disk, the drive make a short read noise and the MSX keeps waiting forever. If I try a "files" command it responds "Disk I/O error" or "Disk offline".

BTW, when I try to format with the internal unit, also seems to respond, but after a second ir stops and issue a "Bad parameter" error message.

I don't know what to do next. Sad

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