User guide

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256K to 512K partition = 128 maximum directory entries
512K to 2 Megabyte partition = 256 maximum directory entries
2 Megabyte to 8 Megabyte partition = 512 maximum directory entries
To calculate the partition size from the number of allocated cylinders, note the following:
1 cylinder = 6 tracks. Each track holds 8K storage. Therefore, each cylinder will hold 48K
storage.
Thus, for the default CP/M partitions of 100 cylinders, you get 48000K storage, or 4.8
megabytes.
For the default HDOS partitions of 25 cylinders, you get 1200K storage, or 1.2 megabytes. For a
rough estimate, simply assume 20 cylinders is equal to one Megabyte. To calculate the
sector/cluster size of your HDOS partitions, use the following formula: ((# CYLINDERS) * (#
HEADS))/8 will give you a value. Take this value, round it up to the next highest even integer value,
and that is the number of sectors taken by each cluster, which is the minimum sector size for any
file. For example, this unit has 6 heads. The standard HDOS partiti ons are set up with a size of 25
cylinders. Therefore:
((25) * (6))/8 = 150/8 = 18.75, rounded up to 20
Thus as set up, your minimum sectors/HDOS cluster is 20.
Under CP/M, you can easily see your pertinent data as to maximum directory entries and the
entire pertinent disk STATUS by using the CP/M command: STAT DSK: