Commodore 1551 User Manual page 37

Even so, you may use the command for reassurance, as often as you like, so long as
you close all your files except for the command channel first.
FORMAT FOR THE INITIALIZE COMMAND
PRINT # 15, "INITIALIZEdrive#"
PRINT # 15, ,. INITIALIZEO"
or it may be abbreviated to
PRINT#15,"Idrive #"
PRINT# 15, "10"
where the command channel is assumed to be opened by file 15, and "drive #" is 0 on
the 1551.
One use for INITIALIZE is to keep a cleaning diskette spinning, if you choose to use
one (under normal conditions, a cleaning diskette is not necessary), If you are using such a
kit, the following short program will keep the diskette spinning long enough for your need
(about 20 seconds):
10 OPENI5,8,15
20 FOR 1= I TO 99
30 : PRINT#15,"IO"
40 NEXT
50 CLOSEI5
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