Category talk:DEC Disk Drives

From Computer History Wiki
Jump to: navigation, search

Adding DEC disk sub-categories?

I plan to add the series of DEC RFxx disk drives (about a dozen) for the DSSI Bus. Without sub-categories the category "DEC Disk Drives" will grow considerably. Should I start creating sub-categories (RP, RM, RA, RD, RF, ...)? Vaxorcist (talk) 15:40, 13 August 2023 (CEST)

I don't have a problem with adding a few categories (e.g. 'DEC Floppy Drives'), but I don't think we need one for each name prefix. The 'Rxyy' drive name itself does that well enough, I think; so no RK, RP, etc categories. What other ones make sense? 'DEC Removable-pack Drives' (for RK, RP, RM - although I guess the RP07 and maybe the RM80 were non-removable)? And I guess 'DEC Fixed-head Drives' for the RS11, RS03, RS04, etc. 'DEC Fixed-pack Drives' (for RA81, ??) I don't know enough about the RD's, etc to have any idea about them. I'm not sure if 'fixed-pack' is the right term to use; I'm too lazy/busy to read the DEC documents and see what term DEC used. Jnc (talk) 16:45, 13 August 2023 (CEST)
There will be about 40 RZxx (SCSI) disk models altogether (not even counting the "newest" ones), too, so a "Winchester" category for all of the fixed disk drives will be quite filled. Why not split them by interface type? Yes, maybe it doesn't make sense to split the MASSBUS drives into different categories. But I think an "MSCP" category would make sense covering all the RAxx and RDxx drives. Additionally one category for the ancient Fixed-head Drives, one for SCSI, and one for DSSI. Vaxorcist (talk) 17:10, 13 August 2023 (CEST)
A 'Winchester' sub-category would makes sense, as would an MSCP sub-category - but that's dividing them by i) internals (the Winchesters) or ii) the interface (the MSCP drives). I think the first question is 'do we use divisions of type i) or type ii) - or both'. ('Both' is something we have done elsewhere - see, for example, Category: QBUS Serial Interfaces and Category: DEC Asynchronous Serial Interfaces. More work - but good for finding things.)
Actually, isn't MSCP layered on top of something else (sorry, I am not very familiar with that generation, to know the answer)? I would think that, if going with ii), it makes sense to divide them into groups which can be plugged in together - can all MSCP drives be plugged into the same controller(s)? (To me, that is a fundamental division: 'can A and B both plug into X'. If not, I think A and B don't belong together in the same lowest-level category - although you might group several sub-categories together into an 'MSCP' category).
Yes, MSCP is on top of a) MFM drives (the smaller ones) and b) SDI drives (the larger ones). MSCP is the access protocol common to both MFM and SDI drives, but you cannot attach an MFM disk to an SDI controller and vice versa. Now things get a little complicated: Are DECs SCSI drives MSCP ones? Probably yes. Are DECs DSSI drives MSCP ones? DSSI drives are a combination of a cluster controller and disk in one ... Got to think a little bit more about that! Vaxorcist (talk) 08:56, 14 August 2023 (CEST)
I read the book "Digital Storage Technology Handbook". Result so far: There should be two sub-categories below "DEC Disk Drives" a) Pre-MSCP Disk Drives (RS, RK, RP, RM) b) MSCP Disk Drives (RD, RA, RF, RZ). Each second-level category could/should several third-level subcategories. Vaxorcist (talk) 13:21, 14 August 2023 (CEST)
You don't want to have a 'floppy' sub-category? Jnc (talk) 18:16, 13 August 2023 (CEST)
Yes, of course yes, but I forgot about it again ... Vaxorcist (talk) 13:21, 14 August 2023 (CEST)

I think having an MSCP category sounds good. I think for the pre-MSCP drives (which also includes the RL's), except for the MASSBUS drives (RS03-4, RP04-7, all the RM's), they all come with drive-specific controller/cabling, so I think the sub-sub-categories there should be 'MASSBUS', 'fixed head', 'removable pack', etc. (Are there any pre-MSCP 'non-removable-pack' drives - other than the fixed-head drives?)

Now that I think about it, the MASSBUS drives also can be divided into those same sub-sub-categories. So maybe we should have two parallel sets of sub-categories: the first set would be sub-categories for the three main generations: pre-MSCP, MASSBUS, and MSCP; the second set would be the type - 'fixed head', 'removable pack', etc. So all drives in the first two generations would be in two categories: generation and type. For the MSCP drives, I leave that entirely up to you! :-) Jnc (talk) 17:38, 14 August 2023 (CEST)

Uniform disk naming

Once we are in the process of editing (almost) all hard disk pages, shouldn't we also assign uniform names at the same time, such as: "RA90 disk drive"? Vaxorcist (talk) 18:00, 15 August 2023 (CEST)

On pages I have touched, I have tried to i) start using standard CHWiki formatting; ii) add links to documentation (some of which I have searched for to add, on Bitsavers and in Manx, although some of it I stumbled across in looking for info on e.g. whether the RM80 was a removable pack drive, or had an HDA); iii) use whatever name DEC seemed to have used in their documentation (which is why we have 'RP07 Disk Drive' and 'RA90 disk drive' - the differing case is what I found in DEC documentation. (For the RM05, I found both, so I had to pick one! Actually, I had the choice of 'RM05 Disk Subsystem' too! :-)
On all the older drives, I have put them in both a i) 'connection' category (custom/MASSBUS/etc) and a 'technology' category (Fixed-head/Removable-pack/Non-removable-media). Whether you do that on the later ones is up to you.
I suppose we should set up a 'DEC Floppy Disk Drives' category; there are a few drives left here, which should go into that. Jnc (talk) 18:29, 15 August 2023 (CEST)