Section 6.4

Standard Restarts

6.4.1  7-track paper tape reader

6.4.1.1  Parity Fail

There are 3 standard restart procedures for parity fail.  When a parity failure occurs a message is printed on the Flexowriter and the reader is disengaged.  The messages are of the form

job-name   geo. name   RESTART n

where n= 2, 1 or 0

The failed character which is on the output side of and adjacent to the character over the reading position should be examined.  If it is of even parity or there is any obvious reason for the failure then the character should be marked and, in general the job abolished.  If it is of odd parity then the appropriate restart procedure should be carried out.

Procedure for RESTART 2.

This ensures that the tape is synchronised with what has already been read.

  (i)  Mark the failed character

 (ii)  Move the tape back one character (this is to allow for the case where the failed character is NL).

(iii)  Move the tape back to between the 2nd and 3rd NL characters beyond (ii) above, but in any case not more than 10 characters beyond the 2nd NL character.

(iv)  Finally, press the Engage button.

Procedure for RESTART 1.

This procedure is as that for RESTART 2 except that (iii) should read:

(iii)  Move the tape back to between the 1st and 2nd NL characters beyond (ii) above, but in any case not more than 10 characters beyond the 1st NL character.

Procedure for RESTART 0.

This allows for a parity fail within the procedure just attempted.  This is to repeat the procedure just attempted so the operator will repeat the procedure from (ii) onwards for the appropriate restart.

6.4.2  Card Reader

There is one standard restart for card failures.  The message printed on the Flexowriter is of the form.

job-name    geo. name    RESTART 1.

and the reader is disengaged.

The procedure is to take and mark the failed card from the reject pocket and to place it at the bottom of the feed-hopper and engage the reader.