User`s manual

FORMAT FOR VALIDATE COMMAND:
PRINT# 15, "VALIDATE"
or abbreviated as
PRINT# 15, "V"
DUPLICATE
This command is a hangover from the operating systems that were
contained on the dual drives like the 4040. It was used to copy entire diskettes
from one drive to another, but has no function on a singledisk drive.
Reading the Error Channel
Without the DOS Support Program, there is no way to read the disk error
channel without a program, since you need to use the INPUT# command which
won't work outside a program. Here is a simple BASIC routine to read the error
channel:
IOOPENI5,8,15 /' ~E
20 INPUT# 15,A$, B$,C~
30 PRINT A$, B$, C$, D$ ~
Whenever you perform an INPUT# operation from the command channel,
you read up to 4 variables that describe the error condition. The first, third, and
fourth variables come in as numbers, and can be INPUT into numeric variables if
you like. The first variable describes the error #, where 0 is no error. The second
variable is the error description. The third variable is the track number on which
the error occurred, and the fourth and final is the block number inside that
track. (A block is also known as a sector)
Errors on track 18have to do with the BAMand directory. For example, a
READ ERROR on track 18 block 0 may indicate that the disk was never
formatted.
CLOSE
It is extremely important that you properly CLOSE files once you are
finished using them. Closing the file causes the DOS to properly allocate blocks
in the BAMand to finish the entry in the directory. If you don't CLOSE the fde,
aDyour data will be lost!
FORMAT FOR CLOSE STATEMENT:
CLOSE file#
You should also be careful not to CLOSE the error channel (channel# 15)
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