AT&T 6300 Programmer's Manual page 397

Syntax
offset
Remarks
Example
PEEK
Function
Returns the byte read from the specified
memory location.
PEEK (offset)
is a numeric expression returning an integer in the range 0
to 65535. It indicates the address of the memory location
from which a byte will be returned. It is the offset from the
current segment, which was defined by the last DEF SEG
statement.
The returned value is an integer in the range 0
to 255.
If "offset" is outside the specified range, an
"Illegal function call" error is returned.
PEEK is the complementary function of the
POKE statement.
A
=
PEEK(&H5AOO)
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