Parallax BASIC Stamp 1, Programming Manual

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5: BASIC Stamp Command Reference – READ
BASIC Stamp Programming Manual 2.0c
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Page 261
READ
BS1 BS2 BS2e BS2sx BS2p
READ Location, Variable
Function
Read value at Location in EEPROM and store the result in result in Variable.
•
Location
is a variable/constant/expression (0 – 255 on BS1, 0 – 2047
on all other BASIC Stamps) that specifies the EEPROM address to
read from.
•
Variable
is a variable (usually a byte) where the value is stored.
Quick Facts
BS1 BS2, BS2e, BS2sx BS2p
Range of
EEPROM
locations
0 to 255 0 to 2047
0 to 2047
(see notes below)
Special
notes
n/a
READ only works with
current program slot on
BS2e and BS2sx.
READ works with any
program slot as set by
the STORE command.
Explanation
The EEPROM is used for both program storage (which builds downward
from address 255 on BS1, 2047 on all other BASIC Stamps) and data
storage (which builds upward from address 0). The READ instruction
retrieves a byte of data from any EEPROM address and stores that byte in
Variable. Any location within the EEPROM can be read (including your
PBASIC program's tokens) at run-time. This feature is mainly used to
retrieve long-term data from EEPROM; data stored in EEPROM is not lost
when the power is removed.
The following READ command retrieves the value at location 100 and
stores it into the variable called Result:
SYMBOL Result = B0
READ 100, Result
--or--
Result VAR BYTE
READ 100, Result
1 2
e
2
sx
2
p
2
1
NOTE: Expressions are not
allowed as arguments on the BS1.
A
SIMPLE
READ
COMMAND
.
1
2
e
2
sx
2
p
2
Table 5.67: READ Quick Facts.