VOGONS


First post, by brettp11

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Hi,

Building my 486 retro PC.

My NEC multisync 6V CDROM works fine after a COLD HARD POWER OFF reset and is recognized in DOS . However, after a soft reset (CTRL-ALT-DEL or reset button), the dos driver gives the error:

CD-ROM drive not ready.
A(Abort) or R(Retry)

Will work fine if I hard power off and boot back up.

Any ideas?

Reply 1 of 10, by Horun

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Do you mean NEC MultiSpin 6V ? maybe has something to do with your HD controller or how you have the jumpers set. Are you using the genuine NEC driver for it ?

Hate posting a reply and have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. 🤣 Second computer a 286 12Mhz with real IDE drive ! After that came 386, 486, Pentium, P.Pro and everything after....

Reply 2 of 10, by pentiumspeed

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IDE/PATA, ATA has reset line as well. This means it is not asserted properly. Cable, controller card please try them.

Cheers,

Great Northern aka Canada.

Reply 3 of 10, by brettp11

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pentiumspeed wrote on 2020-08-01, 21:45:

IDE/PATA, ATA has reset line as well. This means it is not asserted properly. Cable, controller card please try them.

Cheers,

Hi,

CD-ROM is NEC Multspin 6V CDR-1350A EIDE
Controller card is DTC 2278D IDE

I have it connected to the second IDE controller on the card using a 40-pin (80 wire) cable. Had to punch out the plastic plugged pinhole on the controller end of the cable for it to fit.

I’m using the NEC driver, which works great after power on but can’t recognize the drive after a soft reset.

It is an EIDE CD-ROM with an IDE controller. Could that be a problem?

Thank you!

UPDATE:

It is the RESET button. If I reset the machine with the reset button, the CD-ROM drive will not be recognized. A power off and wait for a few seconds and then power on, everything is good. Something is happening to the CD-ROM when I hit the reset button — I hear a click.

Reply 4 of 10, by pentiumspeed

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That's correct, you need to diagnose the reset signal is not asserted issue on your computer. Turn off and on is equivalent of brute forcing the reset line. This is what power supply power good signal does to the reset circuit as well.

Unplug the optical drive and test with hard drive only. If works, prepare a bootable floppy drive with optical drive driver and mscdex included then unplug the hard drive. Do the test again with booting from floppy and optical drive only. If that shows up then you have issue with optical drive or controller card.

What I would go through the process:

Another PATA/IDE cable.
Try different controller card.
Even different optical drive.
If not solved, this might be motherboard's issue. I know this is expensive.

Cheers,

Great Northern aka Canada.

Reply 5 of 10, by brettp11

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Pentiumspeed — thank you so much for your help.

The plot thickens — everything works fine if the CDROM is on the primary IDE controller as SLAVE. I can push the reset button and it loads fine on DOS. If it is on the secondary IDE controller as a master, it will NOT work after a RESET button reset. I push reset button and the drive “clicks” and then at boot it cannot find it. If I power off and back on, it will then work. Any different thoughts?

Reply 6 of 10, by waterbeesje

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Few thoughts came up.

Will a regular hard disk/CF card be detected as secondary master?

What if you set the CDROM as secondary slave? Will it be recognised then? Perhaps with a hard disk as primary if your bios does not accept a slave drive without master.

What if you set an extra delay for detecting drives? If that works/ is possible on your bios of course.

Have you set the detection method to use autodetect everything? Like LBA, PIO, that stuff. Are there differences between primary and secondary?

Could you set the secondary IDE drives to none and on booting OS have drivers loaded? Will it detect then? (Of course that looses CDROM boot, but for testing)

Stuck at 10MHz...

Reply 7 of 10, by pentiumspeed

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Ok that implies the optical drive is not standardized on ATA standard and fails on warm reset.

Try another different optical drive instead. Otherwise, controller card?

Cheers,

Great Northern aka Canada.

Reply 9 of 10, by brettp11

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Awesome ideas guys. I would just operate it as master / slave but the IDE ribbon cord won’t reach so I really wanted to use the CDROM on the secondary controller.

I did get it to work! I tried every idea you guys listed and what finally did it was loading the DTC controller card driver and setting the parameter “/2” which I think initiated the secondary controller on the card. Now the CDROM works after a soft reset, which is great!

Thanks for all of your help!