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Rana Systems Elite Series User Manual

Page 281

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ELITE SERIES USER MANUAL

APPEN. A - DISK I/O

edge of the next we will define as a “bit cell”.

A byte would comprise eight consecutive bit

cells, the most significant of which is normally

referred to as cell 7 (with the least signifi—

cant being cell 0). Data is written and read

serially. During a write operation, bit cell 7

of each byte would be written first and 0 last.

when data is being read from the diskette the

same sequence applies. The third figure illus-

trates the relationship of bits within a byte.

These diagrams are a representation of what

occurs within the disk drive and controller

card. For the purpose of these illustrations,

the hardware interface to the diskette will be

represented as an eight bit “data latch”.

The final figure shows the three bits, 101,

being transferred from the data stream into the

data latch.

P a g e A - 1 0