Research on Micronik HD 1.76 MB Power M-disk

[pipper]

Originally Posted by salteadorneo

One question, what would have to be done to make this modified drive work as an external drive? I have a second Chinon 357A functional, but have not been able to get it to work in a box as a hi unit, it is only recognized as a low drive. I assume that the high density disk signal is not sent to the amiga through the external connector.

It’s possible that the HD switch (which detects the HD hole in the floppy) is not working. For HD drives the switch is not engaged and thus should be closed. You can measure continuity at the switch. If there’s no continuity when there’s no drive inserted, you found the culprit.

I once had a FZ-357A that would detect HD floppies, send the correct DriveID to the Aniga, but eventually would not slow down to 150rpm. End of story: pin1 on the cable was broken. It needs to be grounded for the drive to work in HD mode.

[chrisfi]

I’m closing this request for beta testers. I have more than I can cope with!

I will provide an update once I hear back from them.

Thanks to all those who have offered to test this.

[salteadorneo]

Originally Posted by pipper

It’s possible that the HD switch (which detects the HD hole in the floppy) is not working. For HD drives the switch is not engaged and thus should be closed. You can measure continuity at the switch. If there’s no continuity when there’s no drive inserted, you found the culprit.

I once had a FZ-357A that would detect HD floppies, send the correct DriveID to the Aniga, but eventually would not slow down to 150rpm. End of story: pin1 on the cable was broken. It needs to be grounded for the drive to work in HD mode.

As an internal unit it works correctly, both high and low. It must be a signal that is missing from the outer box itself. I'm going to look at it with other external boxes.

[chrisfi]

Originally Posted by salteadorneo

As an internal unit it works correctly, both high and low. It must be a signal that is missing from the outer box itself. I'm going to look at it with other external boxes.

As Jope posted - when using a HD floppy in an external enclosure you need to bypass the circuit in the enclosure that generates the driveID. In other words, connect pin 34 of the drive to pin 1 of the 23 way D-type.

[salteadorneo]

It was done and it doesn't work. I'm going to check all the connections on that unit. It was done and it doesn't work. I'm going to check all the connections on that unit. The problem must be in the box itself, specifically in the flip-flops of the RDY or MTRX line. The box is from the Golden Image brand. The floppy is a Chinon FB-357A, It may be a problem similar to this https://eab.abime.net/showthread.php?p=1492655
When I modify a Sony, I will test it with several external boxes and I will inform you.

[chrisfi]

Just a quick update using the feedback I have received so far. More to come, but it looks promising

Drives tested and work >

Model...........IC2..........Resistor Replaced?
===========================
T/B53.......D9848N..............Yes..............
Z/131.......BA6986FS...........No...............
E/131.......BA6986FS...........No...............

Many thanks to those testing this and providing feedback

[lesta_smsc]

Originally Posted by chrisfi

If there are any early adopters out there who wouldn’t mind trying it out and reporting back to me, please send a DM.

Must have missed this memo lol

Great to see you're still hard at work.

Ive got around 4-5 different PC drives sitting here: Sony, TEAC, ALPS and I believe the other is Panasonic. Happy to consider modding if it helps, but seems like you've got your hands full already with offers so will wait on finished product

[salteadorneo]

I have tried with three different Sony drives and, for some unknown reason, two of them, with manufacturing dates of 2002 and 2005, do not work as DD drives with Amigaos 3.2.1 (they give read write errors under the workbench) . However, they work perfectly with the Amigaos 3.1. A third unit, made in 2001, works fine with all Amigas I've tried. All units work with the Amiga Test Kit tests. The tests were carried out on two A3000s, one A500 and one A4000, the result was the same on all machines. With an Alps unit I have too, the same errors occurred.

[hooverphonique]

Originally Posted by salteadorneo

I have tried with three different Sony drives and, for some unknown reason, two of them, with manufacturing dates of 2002 and 2005, do not work as HDD drives with Amigaos 3.2.1 (they give read write errors under the workbench) . However, they work perfectly with the Amigaos 3.1. A third unit, made in 2001, works fine with all the friends I've tried. All units work with the Amiga Test Kit tests. The tests were carried out on two A3000s, one A500 and one A4000, the result was the same on all machines. With an Alps unit I have too, the same errors occurred.

AFAIK, amiga os (trackdisk.device) doesn't use the READY signal to determine if the drive is up to speed, but uses a timed delay instead - I wonder if this delay was changed in 3.2.1.

[salteadorneo]

Hello! Is the final version of the Mod close to being published?