The drives initially was working fine, I did buy a lot of use drives a while ago, something like 20 of them, I gave them all a quick test they all seem to working fine. They were supposed to be serviced and tested, but I think a lot of them wasn't. Even so I gave them all a quick test, half of them work, I cleaned them all up and retried them still some of them did not work at all. The ones that did work I was using one in my Falcon, and it tested fine. Thereafter maybe two hours use progressively got worse in reading discs and eventually just stopped. I tried the same drive I think, on a STE, and that would not read the drive either.Pacman wrote: ↑Thu Oct 12, 2017 11:14 am So you're saying that the drives that progressively got worse started out working fine, but within a couple of hours permanently became useless, or it worked fine again the next time you powered up the computer, then once again stopped working an hour or two later? Perhaps due to heat or something... Or maybe just one of those unsolvable computer mysteries![]()
I have not really investigated this, or really taken much time to investigate it. Once the drive failed I have just been basically binning them. I have spent a lot of time in the past trying to service drives and get them working, but the majority the time I just basically gave up.
I can only really assume that once the drive starts warming up starts to malfunction. But I think the lack of pullups on the DNA databus could be a reason why the Sony drives are not working. Maybe the BH chips work better without the pullups. It could down to be tolerances, I really cannot say.
I can only really suggest formatting a floppy, at the control panel and some auto folder program is, just something to autoload from it, then maybe every five minutes reset the machine and see if it loads fine from the floppy drive. Basically leave the machine on all day and keep rebooting it and see if the drive faster malfunction at some point later. It is basically what I was doing.
I think I had this problem on the STFM as well with the Sony drives. I would have used this machine when I initially wrote the article my website a long time ago, but I never investigated it or kept any real notes about it.
Though I do remember I did have a teac drive and some others, I think the teac drive was about £60 back in the day, it was supposed to be a really good drive, but I remember I had nothing but trouble with it and in the end I just chucked it. I know I did test a lot of other drives makes and brands are the time and I gave up with basically all of them other than the Sony ones. Obviously later I discovered there was some drives which were malfunctioning also, which I concluded that the Sony IC drives were all the ones which were malfunctioning.
I think it would be unlikely that so many drives would fail like this, so I think it is just basically a databus falls, as there is no pull-up resistors on the DMA databus. It could just be noise as well, as I found noise understood that every signal anyway. Then if I do come across a Sony IC drive again does show signs of malfunctioning I may try and investigated a little further.
In any case I would recommend pullups on the DMA databus anyway. I did find, I think on the STE, but even the BH drives were showing read errors after a while and it was solved with the pullups. Though of course I cannot really draw any conclusions as are never documented or tested all of this much.
Last time I tested a lot of drives out, I was actually doing some booster work, I thought the changes I was making to the booster code with the reasons for the malfunction, but it did not work even as a stock machine. I remember it annoyed me as I wasted probably two days trying to fix faults which were nothing to do with the booster. As I was busy at the time working on the boosters, I did not really want to start diagnosing floppy drives as well, like I say, I just bend all the if the drives as I don't really have time to mess about with a lot of stuff.