HCS360_01 Datasheet, PDF (12/28 Pages) Microchip Technology – KEELOQ® Code Hopping Encoder

HCS360
FIGURE 4-3:
CRC
(2 bit)
CODE WORD ORGANIZATION (RIGHT-MOST BIT IS CLOCKED OUT FIRST)
Fixed Code Data
Encrypted Code Data
VLOW
(1 bit)
Button
Status
(4 bits)
28-bit
Serial Number
Button
Status
(4 bits)
Discrimination
bits
(12 bits)
16-bit
Sync Value
CRC VLOW
(2 bit) bit
+
Serial Number and
Button Status (32 bits)
MSB
LSB
67 bits
+
32 bits of Encrypted Data of Data
Transmitted
Button Status
(4 bits)
SS S S
21 0 3
Discrimination Bits
(12 bits)
I O U U S S ... S
N V S S E E ... E
D R R R R R ... R
1 0 7 6 ... 0
DS40152D-page 12
 2001 Microchip Technology Inc.