Floppy drive strange behaviour on 486 \ VOGONS

Floppy drive strange behaviour on 486

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First post, by oldgames79

Posted on 2022-03-30, 09:31

oldgames79 Offline

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Hi,

I have a strange behaviour with my floppy drive on a 486.
The bios is correctly configured and the controller is a winbond VLB.
The problem is that , I can't boot from the floppy. It start to read and nothing append, ther is error no message.
But when I boot from the HDD and try to read the floppy, it work.

My tests:
-I try many floppy drive and the result is the same.
-I try on an other motherboard and the result is the same.
-I try many other cable and the result is the same.

It's a faulty controller ? It work on ms-dos and it doesn't work at startup ????

Reply 1 of 7, by Babasha

Posted on 2022-03-30, 09:50

Babasha Offline

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BIOS settings are correct? Is it set as drive A: and 1.44Mb?)

Need help? Begin with photo and model of your hardware 😉

Reply 2 of 7, by oldgames79

Posted on 2022-03-30, 11:59

oldgames79 Offline

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Babasha wrote on 2022-03-30, 09:50:

BIOS settings are correct? Is it set as drive A: and 1.44Mb?)

Yes is set to drive A: and when I'm in MS-DOS I can read the floppy on drive A:

Reply 3 of 7, by Horun

Posted on 2022-03-30, 17:13

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Hmm....odd ! Appears you have the jumpers set to default which should be proper. Are you running the ISA bus at 8Mhz ? The floppy part may not work proper if run at say 10Mhz....

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 4 of 7, by oldgames79

Posted on 2022-03-30, 18:58

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Horun wrote on 2022-03-30, 17:13:

Hmm....odd ! Appears you have the jumpers set to default which should be proper. Are you running the ISA bus at 8Mhz ? The floppy part may not work proper if run at say 10Mhz....

I have an AMD 486 40Mhz and in my bios the AT Bus clock is set to SLCK/5 (40:5=8Mhz) is that correct ?

Reply 5 of 7, by Horun

Posted on 2022-03-30, 19:39

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oldgames79 wrote on 2022-03-30, 18:58:

Horun wrote on 2022-03-30, 17:13:

Hmm....odd ! Appears you have the jumpers set to default which should be proper. Are you running the ISA bus at 8Mhz ? The floppy part may not work proper if run at say 10Mhz....

I have an AMD 486 40Mhz and in my bios the AT Bus clock is set to SLCK/5 (40:5=8Mhz) is that correct ?

Yes ! that should make it 8Mhz. This picture is from a typical AMI BIOS 386/486 motherboard manual

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 6 of 7, by oldgames79

Posted on 2022-03-30, 19:55

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Horun wrote on 2022-03-30, 19:39:

oldgames79 wrote on 2022-03-30, 18:58:

Horun wrote on 2022-03-30, 17:13:

Hmm....odd ! Appears you have the jumpers set to default which should be proper. Are you running the ISA bus at 8Mhz ? The floppy part may not work proper if run at say 10Mhz....

I have an AMD 486 40Mhz and in my bios the AT Bus clock is set to SLCK/5 (40:5=8Mhz) is that correct ?

Yes ! that should make it 8Mhz. This picture is from a typical AMI BIOS 386/486 motherboard manual

The setting in the bios is correct and the floppy at boot freezing.

Reply 7 of 7, by douglar

Posted on 2022-04-01, 00:07

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I had a similar situation and it turned out that the old hard drive had the stoned.e virus on it and it had infected my boot diskette. Once I disinfected the hard drive and boot diskettes, it all worked fine.

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