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NOTE:
Initialize the disk before the buffer read or write.
Examples:
"BLOCK-READ: " 2,0,4,0
"B-R"2,0,4,0
"B-R"2;0;4;0
"B-READ:"2;0;4;0
Parameters following the key words within quotation marks may be separated
by any combination of the following characters:
Character Name
Keyboard Representation
Skip
< cursor right >
Space
Space bar
Comma
The use of these characters permits sending both ASCII strings and integers.
Parameters not within the confines of quotation marks should be separated by
semi-colons (;).
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 posi
tion is accessed with GET# or INPUT#, an End-or-Identify (EOI) is sent. This
terminates 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).
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