Modified Drive (old method,) move to positive on failure
Re: Modified Drive (old method,) move to positive on failure
It should do a single seek in and out and report 0 or so, but not move below track 0 again.
It's the only drive on the cable?
And everything still works normally if the head doesn't stop below 0?
It's the only drive on the cable?
And everything still works normally if the head doesn't stop below 0?
Re: Modified Drive (old method,) move to positive on failure
Yes, it works normally as long as it doesn't stop below 0. What it seems to be doing is a seek 0, which automatically moves the head out until the track 0 sensor trips. Only, since the head is already past 0, it will never hit the sensor, so it just bounces on the physical block, I would assume 79 times (or less, if it had room to move in the first place.) What I have to do, is reach in and shove the head towards the front of the drive during this. Then I have it do another seek to 0 (which then resets it correctly.) I can only do this when the head is trying to move, though. The entire process makes me a bit nervous, really. I don't know how easy it is to mess up a drives alignment. Though, I imagine that seeking to the track 0 sensor would set the alignment each time, and aligning the drive would involve adjusting the location of the sensor. I don't "know" this, though. So, it makes me nervous.
Re: Modified Drive (old method,) move to positive on failure
I thought part of the mod was to extend the "arm" that trips the track 0 sensor so that when below 0, it always is still reporting track 0 via the sensor. At least mine is that way...
Re: Modified Drive (old method,) move to positive on failure
Ah indeed. Is there anything glued to the black plastic part that slides between the sensor?
Re: Modified Drive (old method,) move to positive on failure
Mine was modified with the original method. If I remember, and understand, it correctly.. It would actually disable the sensor briefly after seeking to 0 allow the stepper motor to step past track 0 however many tracks below zero (usually -8,) you set it to. Then it would read, step, read, step, etc.. until it had reached zero again. At which point, it would turn the sensor back on and start reading normally from 0 and above.
Re: Modified Drive (old method,) move to positive on failure
If the bit extending the sensor blocking part is missing you'll have problems.
Re: Modified Drive (old method,) move to positive on failure
Not sure exactly which bit you are talking about. I do know that there is one pin that turns the sensor on/off. Removed that pin from the connector on my 3.5" drive so that it wouldn't ground out (preventing it from working.) it seems to work just fine, other than issues mentioned here. The test uploads to SPS were reported as good. My dumps, when converted, work fine in emulation (those that have formats that support copy protection.) Writing IPF, G64 (with mastering data,) and ADF files all write just fine. Up until my last move, writing RAW files worked fine. Lately, though, it hasn't worked

Re: Modified Drive (old method,) move to positive on failure
The black piece of plastic that moves between the track 0 sensor. It should have an extension glued to it that keeps the sensor blocked while at negative tracks.
Re: Modified Drive (old method,) move to positive on failure
From what I understand, that isn't how the original method worked. The sensor was disabled electronically, not physically. The new method, if I understand it correctly, physically moved the sensor to position -8, making the the triggering line obsolete. Though, it meant having to add -a8 to read a flippy disk, and -a8 -b8 to read a non flippy disk.
Re: Modified Drive (old method,) move to positive on failure
No, there needs to be a piece glued to the sensor arm ALONG WITH the electronic patch.