4.1 BSD mkfs(8) for an RA81?

[Chris Torek]

> ... for comparitive purposes, here's what disk parameters are
> for various kinds of disks, as seen by TOPS-20:
>
> Disk	RECSIZ TRKSIZ CYLSIZ  DSKSIZ
> [...]
> RA81	   512	 161	   1	 128	
> [...]
> RECSIZ := number of 36-bit words/record
> TRKSIZ := number of records in a track
> CYLSIZ := number of tracks/cylinder (number of surfaces)
> DSKSIZ := number of cylinders

That is interesting---and wrong.  There are 14 tracks per cylinder.
In normal terms (I have no idea how you stuff 512 36 bit words into
a 512 byte sector) RA81s have 512 bytes per sector, 51 sectors per
track, 14 tracks per cylinder, and 1248 cylinders, for a total of
891072 blocks or 456,228,864 bytes (~450Mb).
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)
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