Commodore 1581 - Examples of RECORD# Command Usage

byte. It is also possible to store any unsigned integer from 0-65535 in
two bytes, with one byte holding the part of the number that is evenly
divisible by 256, and any remainder in the other byte. In machine
language, such numbers are written backwards, with the low-order
byte (the remainder) first, followed by the high-order byte. In assem
bly language programs written with the Commodore Assembler, the
low part of a two-byte number is indicated by preceding its label with
the less-than character (<). Similarly, the high part of the number is
indicated by greater-than (>).
-NOTE
To avoid the remote possibility of corrupting relative
file data, it is necessary to give RECORD# command once
before the Read or Write access and once after the access.
Although this is not necessary for the 1581, other Com
modore drives require it. To make your programs compati
ble with those other drives, it's a good idea to use it.
EXAMPLES:
In BASIC 7.0, to position the record pointer for file #2 to record
number 3, type:
RECORD#2,3
In BASIC 2.0, to position the recQrd pointer for channel #2 to
record number 3, type:
PRINT #15, "P" +CHR$(98) +CHR$(3) + CHR$(0)
The CHR$(98) comes from adding the constant (96) to the desired
channel number (2). (96 + 2 = 98) Although the command appears to
work even when 96 is not added to the channel number, the constant
is normally added to maintain compatibility with the way RECORD#
works in BASIC 7.0.
Since 3 is less than 256, the high byte of its binary representation
is 0, and the entire value fits into the low byte. Since you want to read
or
write from the beginning of the record, no offset value is needed.
Since these calculations quickly become tedious, most programs
are written to do them for you. Here is an example of a program which
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