THE BUFFER MEMORY SYSTEM’
Before continuing with the operation of the CPT, it’s important to clarify the “buffer memory”
system which is an integral part of the CPT Cassetype System.
The CPT operates with two buffers which act like small “memory banks” within the console. The
Write Buffer holds information as you type it before recording it on tape; the Read Buffer holds
information before reading it out through the typewriter.
Each buffer holds only one record at a time, with a maximum capacity of 200 characters
THE WRITE BUFFER
As copy is typed with RECord on, each character is held in the Write Buffer until one of the follow-
ing signals completes the record and transfers it to tape:
-
-
* carrier return
* Line Return Without Index (Arrow Key)
* Stop Code
* End Page Code
* Switch Code
* Auto Rewind Code
* maximum capacity of 200 characters
NOTE:
The carrier return and the Line Return Without Index must follow printed
characters to create a record.
The Stop Code, End Page Code, Switch Code and Auto Rewind Code will go
directly to tape if there are no printed characters preceding them in the buffer.
When you complete a record by recording one of these seven signals, you will hear a “click” in the
console. That “click” tells you that the “tape head” has recorded the information on tape.
The “tape head” is the reading and recording mechanism in the tape station which comes directly
in contact with the surface of the tape. When recording (in Station 1 only), the tape head transfers
the record from the Write Buffer onto the tape.
Summary of Contents for 4200 Series
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Page 43: ... The final copy of Exercise 6 should look like this 38 ...
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