U UNIVAC 1218 - Bitsavers
U UNIVAC 1218 - Bitsavers
U UNIVAC 1218 - Bitsavers
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3) That-address 00141 is reserved for use by UMTH as an indirect interrupt<br />
address.<br />
4) That the contents of AU, AL, and B prior to entering UMTH need not<br />
be restored upon exit.<br />
5. MAGNETIC TAPE DUPLICATION MODULE (MTDUP)<br />
5.1 PROGRAM DESCRIPTION<br />
The MTDUP module of UPAK III may be used with the computer when operating with<br />
one magnetic tape unit with two transports and an I/O console. The module<br />
copies the content of one magnetic tape (From tape) onto another (To tape).<br />
The normal copy process continues until MTDUP encounters two consecutive<br />
tape marks or until end-of-tape, whichever occurs first.<br />
MTDUP performs the duplication in the following sequence:<br />
1) Rewind From tape and To tape.<br />
2) Read one record from From tape into user-specified buffer.<br />
3) Use buffer control words to determine buffer limits, and write the<br />
record on the To tape. Repeat steps 2) and 3) until two successive tape<br />
marks have been found or end-of-tape is detected.<br />
4) Rewind both tapes if verification option is selected.<br />
5) Read one record from From tape into user-specified buffer and checksum<br />
the record.<br />
6) Read one record from To tape into user-specified buffer and checksum<br />
the record o Compare record checksum for From and To tapes. If not<br />
equal, add one to error counter; repeat steps 5) and 6) until two<br />
successive tape marks or end-of-tape have been found.<br />
7) Rewind both tapes if rewind option was selected.<br />
8) If the error counter is zero, type COPY-OK; otherwise type ERR-XXX<br />
where XXX is the number of copy errors detected.<br />
NOTE: The user may alter the number of successive tape marks terminating<br />
his From tape. To do this, he must store the exact number desired<br />
at MTDUP label CAT.<br />
MTDUP occupies approximately 7128 memory locations and may be loaded anywhere<br />
in computer memory above address 01000 with the restriction that the entire<br />
module must be loaded entirely within one memory bank. The module operates<br />
either under program control or manually from the computer control panel.<br />
IV-B-18