IEI Technology Rocky-3702EV, User Manual, Page: 40 / 48

38
Chapter 5. E
2
Key™ Function
The ROCKY-3702EV provides an outstanding E
2
KEY™ function
for system integrator. Based on the E
2
KEY™, you are free to
store the ID Code, Password or crucial data in the 1Kbit
EEPROM. Because the EEPROM is nonvolatile memory, you
don’t have to worry about losing these 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 anytime.
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 functions for user to
integrate their application with E
2
KEY™ function. These library
(read_e2key and write_e2key) are written and compiled in
C language. Please check the following statement, then you will
know how to use it. It is pretty easy.
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
*/ void write_e2key(unsigned int address,unsigned data)
/* This function will write the given data to E
2
KEY™ at certain
address. The address range is from 0 to 63. The data value is
from 0 to 0xffff. */