Solving the mystery of the [NGEN hard disk type code]

First of all, the very phrasing of this title doesn't feel quite right, because we're working on a Convergent AWS Turbo, which should be a predecessor to the NGEN.  But as it seems, we have no access as of yet to pre-NGEN install disks/programs, so these, which seem to be made for the NGEN, are also AWS backwards-compatible, or so it seems.  At least with the disk we are using right now:

10.2 STANDARD SOFTWARE AWS INITIALIZATION Disk 1 of 1

And, in the menu for hard drive initialization, we see this very important option, that is named exactly that.  Not AWS hard disk type code, but NGEN hard disk type code.

[insert screen picture]

This is an important item, as we find ourselves at a loss on how to specify the physical parameters of the hard disk that we are formatting:  A Seagate ST-251 with 820 cylinders, and 6 heads, 17 sectors per track/cylinder.

Referencing the CONVERGENT TECHNOLOGIES RELEASE NOTICE FOR 11.3 / 11.4 Standard Software (SAA-3100) Revised January 30, 1989 on page 39-41 shows us what we *HOPE* is the right answer:

[NGEN hard disk type code]. A disk type code is a letter (for example, A, B, C) that designates a particular disk drive. It is located on the bad spot report, which is attached to the bottom of the disk module.

IVolume uses the disk type code to determine drive parameters such as number of cylinders, number of heads, and number of sectors per track.

If the hard disk has previously been initialized, IVolume obtains the hard disk type code from the hard disk. If the disk has not been initialized you must enter the hard disk type code here, or optionally when prompted by IVolume.

The supported disk type codes are summarized in the table below. Note that the Size field is unformatted/formatted capacity. When only one size is given that is the formatted capacity. Also, the "S" in the last column means sectors.

Code  Vendor         Size         Cyl   Heads    S
A     Tandon         12.7/10 Mb   306     4     16
B     Seagate        12.7/10 Mb   306     4     16
C     reserved 

D     Atasi          46.5/37 Mb   645     7     16
E     Quantum        42.7/32 Mb   512     8     16
F     MiniScribe     26/20 Mb     612     4     16
G     Seagate        26/20 Mb     612     4     16
H     reserved
J     reserved
K     Micropolis     85/67 Mb    1024     8     16
L     reserved
M     reserved
Q     Quantum SCSI   80 Mb        823     5     38
R     Quantum SCSI   50 Mb        823     6     21
S     Seagate SCSI   20 Mb        613     4     17
T     Micropo SCSI   140 Mb      1016     8     34
U     Micropo SCSI   326 Mb      1217     15    35
V     Quantum SCSI   40 Mb        834     3     32
W     Seagate SCSI   40 Mb        613     6     25

If your disk drive is not supported by a disk type code, you may enter the actual drive parameters when prompted to enter the code. Enter the parameter data as

cylinders/heads/sectors.

For example, if your drive parameters are 1024 cylinders, 4 heads, and 16 sectors per track, enter the parameter data as follows:

          1024/4/16

So, there it is, in the final paragraphs, how to manually enter the parameters of the disk!  syntax is crucial, and can be easy to guess only if you know the lay of the land for this install system and CTOS, so to speak...neither of which we do as of yet, so this is very helpful.

Finding the answers to this parameter were a bit enigmatic, but we can thank a Google Search of the exact phrase to turn up a PDF document from an unexpected source.  (see my notes on the "Manuals" tab of this website)