Disabling write-protect on Uni-Disk 5.25 for 2 series?

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Disabling write-protect on Uni-Disk 5.25 for 2 series?

Like it says on the cover. Is there a simple way to disable the write-protect feature on 5.25 drives, model A9M0107? These are the ones in the white plastic case with the permanently attached DB-style cable.. The ones with the pass-through option.

No cutting or soldering of wires are allowed. Nor is breaking loose the optical sensor. Anything I do will need to be 100% reversible.

Well off to find the schematics and perhaps work from there.

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

Hole puncher on the disks themselves not an option also????

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

In the case of keeping top-dollar floppies in original condition. No it is not.

I just found a ridiculously simple jumper-wire mod that worked perfectly. Thanks anyways!

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

Nice thinkpuzzle....

"---------------------------------------------------- solution to question removed -----------------------------------------------------------------------------------------------------------------------------------------"

EDIT: solution removed......
it´s time to leave the quiz for other to solve too.......
happy puzzeling !

speedyG

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

I used only a Phillips screwdriver as my working tool.

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

Hello Keatah,
then there must be a second solution tooo....
i guess although i didn´t ever have the need to open a 3,5 drive, that a wire is clamped and not soldered ?
at least with your solution you´ll have to reopen the drive again, to get back to former status....
because with my solution you need a male plug, 2 resistors, a switch, a female plug and some wire and a soldering iron...
with my solution you don´t even need to open the drive.... you just remove my external solution...
cheers...

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

I was working over at a friend's house. She doesn't have everything needed to fabricate an in-line dongle-plug-adapter. And it would have necessitated a trip to RadioShack to get switches and pull resistors, wires, capacitors for noise & debounce, and other materials.

I needed a solution now so we could get on with copying and restoring some old disks without punching holes in them.

My solution was simple, wedge the screwdriver in under the C1 cable in such a way that the cable held it against J29 and R12. Proof of concept.. It worked!

I made it more "permanent" by rolling up a bit of foil into the shape of a wire and stuffed each end under the two previously mentioned parts. The drive can be "restored" by pulling out the makeshift wire. But I suspect we'll leave it in place.

Simple, Elegant, and McGyverish!

Perhaps when I have time to spare I could build up a dongle, and take it further by toggling it through some address or gameport or something. Include some lights to say what condition it's in. Build in a one-time-use timer, push it and the disk is de-write-protected for say 2 minutes or 20 minutes. Or all manual, with force write/no-write, original. Include a track status indicator, the head is at track XX now. Include a read-write indicator, red=writing, green=reading. Yellow=motor idle. Toggle switch to swap disk #1 to disk #2. 5 digit RPM indicator with buttons to tweak it up and down. Magnetic flux signal strength indicator. Quarter track and half track directional nudging. Manual track positioning. Head sweep 0-34, 34-0, for exercising and cleaning purposes. Data bus monitoring. Head temperature, stepper & driver motor temperature, current draw and voltage levels. USB interface to connect to PC or 1-button transfer of floppy-to-image. Bit-stepping. Place "0" or "1" at any position on the disk. Precision encoder to monitor angular position. Auto-calibration. Clock timing adjust. Graphically lay out a track and drag'n'drop bits. Telemetry to the PC via WiFi. Physical mission-control sci-fi-looking panel with lights and knobs and switches: mirrored on a skinnable PC window. Sound effects generator. Arduino & Altera powered. Lots of ideas!

Yes, a Disk ][ ST-Edition! I like it!

Anything else?

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

Someone had an item like this for sale up on eBay a while back.
A Disk ][ with a switch on the side that you could flip and
the disk could not be written to.
Probably the same concept maybe? Smile

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

Absolutely yes. This was one of the first mods I did to to my Disk II back in the day. There were several ways of carrying out this modification.

If you know anything about the internal workings of the original Disk II drives (metal housing) - it was a simple matter to reposition the detect switch by removing one screw. Which is what I did.

You could re-wire the switch or make splices and jumpers. All of this was talked about in various tips & tricks articles. No doubt.

Drill holes and mount a switch, very common things. It was typical for someone in the warez scene to mod drive #2 with two things. Adjust down the speed to 296-298 RPM, and deactivate write protect. Drive #1 was left as is.

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Re: Disabling write-protect on Uni-Disk 5.25 for 2 series?

Adjust down the speed to 296-298 RPM, and deactivate write protect.

this was done for use of deprotecting quite a lot of games, because several protection schemas operated with
slower drivespeed to prevent from making copies of the disk.... for example nearly all games from SSI...

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Sorry to open an old post.

Sorry to open an old post. This jumper solution (R12 - J29) works for drive model A9M0107. Does anyone know how to disable the write-protect on a A9M104 drive?  I annot see a R12 or J29 on the board for this model.

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Don't feel bad.  I just got

Don't feel bad.  I just got an A9M0107 and had no idea this was even a possible option and was planning to hole-punch some disks.  I'm super excited to try this instead and never would have known about this if you hadn't bumped it to be a current thread.  :-)

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very cool

I just tried this on my drive; worked great.  Thanks for the info !

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