DataSheet.jp

HCS512-P の電気的特性と機能

HCS512-PのメーカーはMicrochip Technologyです、この部品の機能は「KEELOQ CODE HOPPING DECODER」です。


製品の詳細 ( Datasheet PDF )

部品番号 HCS512-P
部品説明 KEELOQ CODE HOPPING DECODER
メーカ Microchip Technology
ロゴ Microchip Technology ロゴ 




このページの下部にプレビューとHCS512-Pダウンロード(pdfファイル)リンクがあります。

Total 20 pages

No Preview Available !

HCS512-P Datasheet, HCS512-P PDF,ピン配置, 機能
M
HCS512
Code Hopping Decoder
FEATURES
Security
• Secure storage of Manufacturer’s Code
• Secure storage of transmitter’s keys
• Up to four transmitters can be learned
• KEELOQ code hopping technology
• Normal and secure learning mechanisms
Operating
• 3.0V – 6.0V operation
• 4 MHz RC oscillator
• Learning indication on LRNOUT
• Auto baud rate detection
• Power saving sleep mode
Other
• Stand alone decoder
• On-chip EEPROM for transmitter storage
• Four binary function outputs–15 functions
• 18-pin DIP/SOIC package
Typical Applications
• Automotive remote entry systems
• Automotive alarm systems
• Automotive immobilizers
• Gate and garage openers
• Electronic door locks
• Identity tokens
• Burglar alarm systems
Compatible Encoders
• HCS200, HCS300, HCS301, HCS360, HCS361
• NTQ106
DESCRIPTION
The Microchip Technology Inc. HCS512 is a code hop-
ping decoder designed for secure Remote Keyless
Entry (RKE) systems. The HCS512 utilizes the pat-
ented KEELOQ code hopping system and high security
learning mechanisms to make this a canned solution
when used with the HCS encoders to implement a uni-
directional remote keyless entry system.
PACKAGE TYPE
PDIP, SOIC
LRNIN
LRNOUT
NC
MCLR
GND
S0
S1
S2
S3
1
2
3
4
5
6
7
8
9
18 RFIN
17 NC
16 OSCIN
15 OSCOUT
14 VDD
13 DATA
12 CLK
11 SLEEP
10 VLOW
BLOCK DIAGRAM
RFIN
67-Bit Reception Register
EEPROM
CONTROL
OSCIN OSCILLATOR
DECRYPTOR
DATA
CLK
LRNIN
SEL
MCLR
SLEEP
OUTPUT
CONTROL
S0 S1 S2 S3 VLOW LRNOUT
The Manufacturer’s Code, transmitter keys, and syn-
chronization information are stored in protected on-chip
EEPROM. The HCS512 uses the DATA and CLK inputs
to load the Manufacturer’s Code which cannot be read
out of the device.
The HCS512 operates over a wide voltage range of
3.0 volts to 6.0 volts. The decoder employs automatic
baud rate detection which allows it to compensate for
wide variations in transmitter data rate. The decoder
contains sophisticated error checking algorithms to
ensure only valid codes are accepted.
© 1997 Microchip Technology Inc.
DS40151C-page 1

1 Page





HCS512-P pdf, ピン配列
HCS512
The 16-bit synchronization value is the basis for the
transmitted code changing for each transmission and is
updated each time a button is pressed. Because of the
complexity of the code hopping encryption algorithm, a
change in one bit of the synchronization value will result
in a large change in the actual transmitted code. There
is a relationship (Figure 1-3) between the key values in
EEPROM and how they are used in the encoder. Once
the encoder detects that a button has been pressed,
the encoder reads the button and updates the synchro-
nization counter. The synchronization value is then
combined with the encoder key in the encryption algo-
rithm, and the output is 32 bits of encrypted information.
This data will change with every button press, hence, it
is referred to as the hopping portion of the code word.
The 32-bit hopping code is combined with the button
information and the serial number to form the code
word transmitted to the receiver.
1.3 HCS Decoder Overview
Before a transmitter can be used with a particular
receiver, the transmitter must be ‘learned’ by the
receiver. Upon learning a transmitter, information is
stored by the receiver so that it may track the
transmitter, including the serial number of the
transmitter, the current synchronization value for that
transmitter, and the same encoder key that is used on
the transmitter. If a receiver receives a message of valid
format, the serial number is checked and, if it is from a
learned transmitter, the message is decrypted and the
decrypted synchronization counter is checked against
what is stored. If the synchronization value is verified,
then the button status is checked to see what operation
is needed. Figure 1-3 shows the relationship between
some of the values stored by the receiver and the val-
ues received from the transmitter.
FIGURE 1-2: BASIC OPERATION OF TRANSMITTER (ENCODER)
Transmitted Information
EEPROM Array
Encoder Key
Sync Counter
Serial Number
KEELOQ
Encryption
Algorithm
32 Bits of
Encrypted Data
Serial Number
Button Press
Information
FIGURE 1-3: BASIC OPERATION OF RECEIVER (DECODER)
EEPROM Array
Encoder Key
Sync Counter
Serial Number
Manufacturer’s Code
Check for
Match
KEELOQ
Decryption
Algorithm
Button Press
Information
Serial Number
32-Bits of
Encrypted Data
Received Information
Check for
Match
Decrypted
Synchronization
Counter
© 1997 Microchip Technology Inc.
DS40151C-page 3


3Pages


HCS512-P 電子部品, 半導体
HCS512
4.0 DECODER OPERATION
4.1 Learning a Transmitter to a Receiver
Either the serial number-based learning method or the
seed-based learning method can be selected. The
learning method is selected in the configuration byte. In
order for a transmitter to be used with a decoder, the
transmitter must first be ‘learned’. When a transmitter is
learned to a decoder, the decoder stores the encoder
key, a check value of the serial number and current syn-
chronization value in EEPROM. The decoder must
keep track of these values for every transmitter that is
learned. The maximum number of transmitters that can
be learned is four. The decoder must also contain the
Manufacturer’s Code in order to learn a transmitter. The
Manufacturer’s Code will typically be the same for all
decoders in a system.
The HCS512 has four memory slots. After an “erase all”
procedure, all the memory slots will be cleared. Erase
all is activated by taking LRNIN low for approximately
10 seconds. When a new transmitter is learned, the
decoder searches for an empty memory slot and stores
the transmitter’s information in that memory slot. When
all memory slots are full, the decoder randomly over-
writes existing transmitters.
4.1.1 LEARNING PROCEDURE
Learning is activated by taking the LRNIN input low for
longer than 64 ms. This input requires an external pull-
up resistor.
To learn a new transmitter to the HCS512 decoder, the
following sequence is required:
1. Enter learning mode by pulling LRNIN low for
longer than 64 ms. The LRNOUT output will go
high.
2. Activate the transmitter until the LRNOUT output
goes low indicating reception of a valid code
(hopping message).
3. Activate the transmitter a second time until the
LRNOUT toggles for 4 seconds (in secure learn-
ing mode, the seed transmission must be trans-
mitted during the second stage of learn by
activating the appropriate buttons on the trans-
mitter).
If LRNIN is taken low momentarily during the
learn status indication, the indication will be ter-
minated. Once a successful learning sequence
is detected, the indication can be terminated
allowing quick learning in a manufacturing setup.
4. The transmitter is now learned into the decoder.
5. Repeat steps 1-4 to learn up to four transmitters.
6. Learning will be terminated if two non-sequential
codes were received or if two acceptable codes
were not decoded within 30 seconds.
The following checks are performed on the decoder to
determine if the transmission is valid during learn:
• The first code word is checked for bit integrity.
• The second code word is checked for bit integrity.
• The hopping code is decrypted.
• If all the checks pass, the serial number and syn-
chronization counters are stored in EEPROM
memory.
Figure 4-1 shows a flow chart of the learn sequence.
FIGURE 4-1: LEARN SEQUENCE
Enter Learn
Mode
Wait for Reception
of a Valid Code
Wait for Reception
of Second
Non-Repeated
Valid Code
Generate Key
from Serial Number
or Seed Value
Use Generated Key
to Decrypt
Compare Discrimination
Value with Serial Number
Equal
?
No
Yes
Learn successful. Store:
Serial number check value
Synchronization counter
Encoder Key
Learn
Unsuccessful
Exit
4.2 Validation of Codes
The decoder waits for a transmission and checks the
serial number to determine if the transmitter has been
learned. If learned, the decoder decrypts the encrypted
portion of the transmission using the encoder key. It
uses the discrimination bits to determine if the decryp-
tion was valid. If everything up to this point is valid, the
synchronization value is evaluated.
DS40151C-page 6
© 1997 Microchip Technology Inc.

6 Page



ページ 合計 : 20 ページ
 
PDF
ダウンロード
[ HCS512-P データシート.PDF ]


データシートを活用すると、その部品の主な機能と仕様を詳しく理解できます。 ピン構成、電気的特性、動作パラメータ、性能を確認してください。


共有リンク

Link :


部品番号部品説明メーカ
HCS512-IP

KEELOQ CODE HOPPING DECODER

Microchip Technology
Microchip Technology
HCS512-ISN

KEELOQ CODE HOPPING DECODER

Microchip Technology
Microchip Technology
HCS512-P

KEELOQ CODE HOPPING DECODER

Microchip Technology
Microchip Technology
HCS512-SN

KEELOQ CODE HOPPING DECODER

Microchip Technology
Microchip Technology


www.DataSheet.jp    |   2020   |  メール    |   最新    |   Sitemap