HELP 720 FLOPPY AS FLP1_

[mhanias]

Please help! My nec 720 floppy is dead! It connected with trump card.
I found a citizen OSDA -39C 720 floppy but it does not work as flp1_.
I want to know how can treat the jumbers to be ds0.
I have attach pic if it can help you.
Best wishes
Mike

[Pr0f]

Any chance you can post pictures of :

The side - if any switches / jumpers are present there
The back where the connectors are
The underside
The top - showing the are where the connectors are

The location of the drive selects is usually in one of these areas. They may be switches, jumpers or even just solder bridge selects.



These cover TEAC drives - but you get the idea: https://embeddedsw.net/EMUFDD_TEAC_Jumpers.html

[Derek_Stewart]

Hi,

If you can take the bottom cover off the drive and does it resemble:

Which is a OSDA-90C

There are solder points JJ13 that has 1 0 with an arrow head pointing to 1, which could default to drive 1 (FLP2)

Maybe a short at J13 may give DS0 on J13

Only a guess, as I could not find the OSDA-39C at all.

[mhanias]

Thank you for your reply. This is the bottom of the drive

[mhanias]

Can you send me the default jumper set

Regards
Mike

[Pr0f]

Is that a switch at "DSSW2" on the board - next to the stepper motor ?

If so - I suspect that's the drive select switch.

[mhanias]

Yes there is a switch. I put it on 0 . But the trump card did not recognised it as flp1_ .
I need the location of jumbers on the upper side near the power
Mike

[mhanias]

It works!! I I put the jumper in third position.
Thank you very much Derek

[Pr0f]

Excellent news