The use of these characters permits sending both ASCII strings and integers.
Parameters not within the confines of quotation marks should be separated by
semicolons (;).
In the following discussions, a PRINT# is assumed in all examples.
BLOCK-READ
This diskette utility command provides direct access to any block on a diskette
in either disk drive. Used in conjunction with other block commands, a random
access file system may be created through BASIC. This command finds the
character pointer in the 0 position of the block. When a character in this position
is accessed with GET# or INPUT#, an End-or-Identify (EOI) is sent. This termi-
nates an INPUT# and sets the Status Word (ST) to 64 in the computer.
The format "B-R"ch;dr;t;s is illustrated in the following example.
Example:
"B-R"5;0;18;0
Reads the block from track 18, sector 0 into channel 5 buffer area.
After using BLOCK READ to transfer the data to the buffer, the data may be
transferred to memory by INPUT# or GET# from the logical file opened to that
disk channel (i.e. , using that secondary address).
The U1 command described under USER is similar to the BLOCK-READ
command.
BLOCK-WRITE
When this command is initiated, the current buffer pointer is used as the last
character pointer and is placed in the 0 position of the new buffer. The buffer is
then written to the indicated block on the diskette and the buffer pointer is left
in position 1.
The format "B-W"ch;dr;t;s is illustrated in the following example.
Example:
"B-W"7;0;35;10
Writes channel 7 buffer to the block on track 35, sector 10: BLOCK-
WRITE is not available with DOS 2.
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