HCS512-IP Microchip Technology, HCS512-IP Datasheet - Page 8

• Manufacturer Part Number: HCS512-IP
• Description: KEELOQ CODE HOPPING DECODER
• Manufacturer: Microchip Technology

HCS512
5.0
The HCS512 can act as a stand alone decoder or be
interfaced to a microcontroller. Typical stand alone
applications include garage door openers and elec-
tronic door locks. In stand alone applications, the
HCS512 will handle learning, reception, decryption,
and validation of the received code; and generate the
appropriate output. For a garage door opener, the
HCS512 input will be connected to an RF receiver, and
the output, to a relay driver to connect a motor control-
ler.
Typical systems where the HCS512 will be connected
to a microcontroller include vehicle and home security
systems. The HCS512 input will be connected to an RF
receiver and the function outputs to the microcontroller.
The HCS512 will handle all the decoding functions and
the microcontroller, all the system functions. The serial
output mode with a 1- or 2-wire interface can be used if
the microcontroller is I/O limited.
DS40151C-page 8
INTEGRATING THE HCS512
INTO A SYSTEM
6.0
The PG306001 production programmer will allow easy
setup and programming of the configuration byte and
the manufacturer’s code.
6.1
The configuration byte is used to set system configura-
tion for the decoder. The LRN bits determine which
algorithm (Decrypt or XOR) is used for the key genera-
tion. SC_LRN determines whether normal learn (key
derived from serial number) or secure learn (key
derived from seed value) is used.
TABLE 6-1:
TABLE 6-2:
Bit
0
1
2
3
4
5
6
7
LRN0
0
1
SC_LRN
SLEEP
Name
LRN0
LRN1
RES1
RES2
RES3
RES4
DECODER PROGRAMMING
Configuration Byte
CONFIGURATION BYTE
LEARN METHOD LRN0, LRN1
DEFINITIONS
Secure Learn enable (1 = enabled)
Sleep enable (1 = enabled)
Decrypt algorithm
Learn algorithm select
XOR algorithm
1997 Microchip Technology Inc.
Description
Description
Not used
Not used
Not used
Not used
Not used