AT&T 6300 Programmer's Manual page 179

Example
Example
BLOAD
Command
If "offset" is specified, a DEF SEG statement
should be executed before the BLOAD. When
"offset" is given, GWBASIC assumes you
want to BLOAD at an address other than the
one saved. The last known DEF SEG address
will be used. If no DEF SEG statement has
been given, the GWBASIC data segment is
used as the default (because it is the default for
DEF SEG).
Warning
BLOAD does not perform an address range
check. It is possible to load a file anywhere in
memory. Be careful not to load over
GWBASIC or the operating system.
10 'Load a machine language program
20 'into memory at 60:FOOO
30 'Restore Segment to GWBASIC's OS.
40 OEF SEG
50 'Load PROG1 into the OS.
60 BLOAO uB:PROG1",&HFOOO
10 'Load the screen buffer
20 'Point segment at screen buffer
30 OEF SEG = &HBBOO
40 'Load FILE1 into screen buffer
50 BLOAO uFILE1",0
Note the DEF SEG statement in 30 and the
offset of 0 in 50: this guarantees that the
correct address is used.
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