HP Forum Archive 06

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HP-IL (71B) with 9114B QUESTION Message #1 Posted by Mike on 19 Aug 2001, 12:01 a.m. I have 3 9114B disk drives. I've been trying to test them using an HP-71B with HP-IL interface. The HP-IL interface does not mention the drive anywhere. I've tried a few things and get "loop broken" or some such error. I have occasionally seen the lights react to a command. I don't think there is an HP-IL problem. All there 9114B behave the same. I think it has something to do with INITIALIZING or ASSINGING the device or something like that. Can someone tell me the INITIALIZATION sequence to initialize and use the 9114B with the 71B and an HP-IL interface. The 9114B is the only device in the loop. Thanks

Re: Followup Questions Message #2 Posted by Mike on 19 Aug 2001, 12:35 p.m., in response to message #1 by Mike I have three that have the same symptoms. Could be I have a problem, as the self-test light stays on, indicating a failure. Sometimes, it goes out and I then get a different error. The battery level is blinking at it's lowest level. Could this cause a self-test failure? I do also have the AC Adapter connected. Is there a likely common failure mode for these? Thanks

Re: Followup Questions Message #3 Posted by Raymond Hellstern on 19 Aug 2001, 1:46 p.m., in response to message #2 by Mike Hi, your devices battries are dead. The HP-IL loop will be 'broken'. The replacement battery from Panasonic is 'LCR 6V2.4P' and costs about $15-$20. Regards, Raymond

Thanks to all in this thread and others offline Message #4 Posted by Mike on 20 Aug 2001, 11:55 a.m., in response to message #3 by Raymond Hellstern Thanks to all who responded. And thanks to Dale Richmond for providing me with some useful information. The problem turned out to be dead batteries. I made up a very nice cable, thanks to suggestion from Dale. The cable plugs into the connection that the battery would use. This provided the needed power to test my drives. They all function just fine. So now, I will try and find some replacement LCA cells. Thanks

Re: Followup Questions Message #5 Posted by Tony Duell on 19 Aug 2001, 2:43 p.m., in response to message #2 by Mike It is impossible for a self-test error to change the state of the battery LEDs (said LEDs are controlled by a set of analogue comparators at the front of the PCB), but it's entirely possible for a low battery to cause a self-test error. One of the tests is a 'seek to track 0' -- it moves the head on and off the outermost track of the disk and makes sure the track 0 sensor triggers at the appropriate time. A low battery may cause the stepper motor to malfunction, so that test will fail. Also, the +5V lines (there are 2, one for the most of the logic, and one for the RAM and HPIL chips -- the software power-down of the drive doesn't turn the latter off) are produced by linear regulators from the battery voltage. So they're always less than the battery voltage. If the battery is low (<5V), then the 5V line may be low and the logic chips might do the Wrong Thing. Start by sorting out the battery. Then get the drive to pass the self-test every time, then connect it to the HP71. OK, the battery. Take out the battery module, and take off the cover (2 TX9 screws on top). Inside there's a lead acid battery block and a little charger PCB. By now the battery will need replacing. If you can't get the original type (and they're very hard to find in the UK), then 3 2.5Ah Cyclon cells (2V each, lead acid) in series will work, and fit _perfectly_ into the housing. Of course the red wire is the +ve one. When you've got a known-good battery, put it in the drive and see if it now passes the self-test (TEST LED out, all the battery LEDs on). If it does, then connect it to the HP71 (with 2 HPIL cables -- yes, that is obvious to old hands, but I've seen people try to connect 2 devices with 1 cable...), turn on the drive, then turn on the 71. Before you try any disk-related commands, try DEVID$(1) (and press END LINE). That asks the first (or only) device on the HPIL for it's identification string (normally the model number). I know the HP9114B resonds to this, and sends back the string "HP9114B". If you get that far, then much of the logic in the drive unit is working properly. Then we can try som disk-related commands. Incidnetnally, a point of trivia for HP experts. You mentioned that the battery empty LED was blinking. Actually, it's _always_ blinking while the drive is powered up (it's driven from a good old 555 astable ;-)). It's just that it blinks too fast to see (about 120Hz IIRC) when the battery is above a certain voltage.

Re: HP-IL (71B) with 9114B QUESTION Message #6 Posted by Raymond Hellstern on 19 Aug 2001, 1:37 p.m., in response to message #1 by Mike e.g. INITIALIZE TEST1:A,55 Inizializes the medium in the device at address A with 55 cat entries. The medium gets the name 'TEST1' This is an example from the HP-71 HP-IL interface pocket guide. Raymond

Re: HP-IL (71B) with 9114B QUESTION Message #7 Posted by Steve (Australia) on 20 Aug 2001, 12:12 a.m., in response to message #1 by Mike If you have a 9114A/B make sure you're not sufffering from the "saggy floppy" problem. First, when you eject the disc, does it come out smartly, or is there a slight delay, and a sort of oozy behaviour? Or if it gets worse, do you sometimes find you have to manually pull the disk out? Does the mechanism sometimes fall back to the "disk inserted" position after you remove a disk, meaning that you have to press the eject button to actually insert the disk? If you have either of these problems, then you should quite smartly move to clean up the glue that HP used for a lubricant on these drives. Note that in my experience it is generally only those drives that have spent a long time at elevated temperatures and/or dusty conditions that seem to suffer from this problem. The oozy drive problem is not serious per se, however one day it will get bad enough that you may find that you're ripped the head(s) from your floppy drive. All very sad.

Re: HP-IL (71B) with 9114B QUESTION Message #8 Posted by Tony Duell on 20 Aug 2001, 5:18 p.m., in response to message #7 by Steve (Australia) The grease-turned-to-glue problem mainly occurs in the older full-height 3.5" Sony drives, used in the 9114A, 9133, 9121/2/3, etc. A little latch in the disk holder doesn't engage and the disk holder doesn't stay in the 'up' position. The result, if you are unlucky is a ripped-off upper head (and you get the 'fun' of replacing the head carriage and re-aligning it -- I've done this once in a 9133, and it was not that hard given a 'scope and alignment floppy. But it's easier to replace the grease before this occurs, even though to do it properly you have to dismantle a large part of the drive (I can post the step-by-step procedure if anyone's interested). The 9114B uses a later Sony drive mechanism, half height (with an overgrown front panel). It's similar to the Apple 800K drive (used in the Mac+, etc), to the extent that many parts (stepper, head carriage, motor driver chips, analogue ASIC, etc) can be interchanged between the 2 types of drive. An old Apple Mac+ drive is one of the best sources of spares for the 9114B. I've never seen one of those with a sticky eject problem, and I don't think it's likely to happen (the mechanism is totally different, so the same problem can't really occur). A few points, though. Even though the 9114B drive has a 34 pin cable, don't use a PC type of drive in that unit. For one thing, the pinout is non-standard (on a PC, all odd numbered pins are ground, on the 9114B, there's +5V and +12V on some of them -- there's no separate power connector). For another thing, the 9114 drives (both versions) spin at 600rpm -- twice as fast as a PC drive, and thus the controller is set up for a double-speed data rate. Realigning the cotnroller for a normal PC drive is possible, but not trivial (don't attempt to fiddle unless you have the WD279x data sheets and understand them!). When I said the drive mecahnism in the 9114B was similar to that in the Mac+, I was not joking. There's even space on the PCB and holes in the main chassis for a motorised eject option (although the 9114B controller wouldn't handle it even if it was installed). About the only significant difference is the digital ASIC, because the Apple Mac disk interface is just plain strange...

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