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Read Named Program File – USR(0) (CLOAD equivalent)

Read a cassette tape and search for a file name which matches with the required program name. When a match is found, read the program into memory.

After entry of the USR(0) statement, the prompt

rName:

appears on the next screen line and the required program name is entered on that line. If the first program is required (irrespective of the name) just press ENTER at this point. Optionally, ‘transparent’ characters may be entered as part of the required program name. A transparent character will match with any character read into that position. The transparent Character is ASCII 7FH. (CONTROL:SHIFT:/)

The tape drive LED is switched on and the cassette tape is searched for tape and file labels. Any tape labels detected are displayed on the top line of the screen without interruption of the command. As each file or program label is detected, the name is displayed on the screen line immediately below the required program name. Any name or text which was previously displayed on that line is blanked out. The program name and the required name are compared. A required program name will match with an identical name read from cassette tape. Also, required name will match with a longer name read from tape, providing that all the characters match up including the last character (ie. last non-space) of the required name. If a file name read from cassette tape fails to match the required name, the search continues. When a match is found, the program is read into memory,

Between entry of the required program name and a successful name match, the command may be terminated by first stopping the cassette tape recorder and then typing four ESC (SHIFT:ENTER) characters. Four consecutive ESC characters read from cassette tape will have the same effect.

The command will also recognise as program names, any file names written using the SYS-EX “w” command. If a file which is not a BASIC program file matches with the required name and is read into memory, it may be necessary to RESET the computer and to cold start BASIC once again. (NAS-SYS “J”)

Verify Named Program File – USR(1) (CLOAD? equivalent)

Read a cassette tape and search for a file name which matches with the required program name. When a match is found, read the program but do not load it into memory.

After entry of the USR(1) statement, the prompt

vName: