37
5
E
2
Key™
Function
The ROCKY-P248SV provides an outstanding E
2
KEY™
function
for system integrator. Based on the E
2
KEY™
you could free to
store the ID Code, Pass Word, or Critical Data in the 1Kbit
EEPROM. Because the EEPROM is nonvolatile memory, you
don’ t have to worry the losing of the very important data.
Basically the E
2
KEY™
is based on a 1Kbit EEPROM which is
configured to 64 words(from 0 to 63). You could access (read or
write) each word at any time.
When you start to use the E
2
KEY™
you should have the utility in
the package. The software utility will include four files as follows,
README.DOC
E2KEY.OBJ
EKEYDEMO.C
EKEYDEMO.EXE.
The E2KEY.OBJ provides two library function for user to
integrate their application with E
2
KEY™
function. These library
(read_e2key and write_e2key)
are written and compiled in C
format. Please check the following statement, then you will know
how to implement it easily.
unsigned int read_e2key(unsigned int address)
/* This function will return the E
2
KEY™
’ s data at address. The
address range is from 0 to 63. Return data is one word,16 bits */
