HCS300
DS21137E-page 4
Preliminary
1999 Microchip Technology Inc.
FIGURE 1-2:
BASIC OPERATION OF TRANSMITTER (ENCODER)
FIGURE 1-3:
BASIC OPERATION OF RECEIVER (DECODER)
K
EE
L
OQ
Algorithm
Button Press
Information
Encryption
EEPROM Array
32 Bits of
Encrypted Data
Serial Number
Transmitted Information
Encryption Key
Sync Counter
Serial Number
Button Press
Information
EEPROM Array
Encryption Key
32 Bits of
Encrypted Data
Serial Number
Received Information
Decrypted
Synchronization
Counter
Check for
Match
Check for
Match
K
EE
L
OQ
Algorithm
Decryption
Sync Counter
Serial Number
Manufacturer Code
21137e.Book Page 4 Monday, October 4, 1999 8:04 AM
