hcs412 Microchip Technology Inc., hcs412 Datasheet
hcs412
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hcs412 Summary of contents
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... Automotive remote entry systems • Automotive alarm systems • Automotive immobilizers • Gate and garage openers • Electronic door locks (Home/Office/Hotel) • Burglar alarm systems • Proximity access control 2002 Microchip Technology Inc. HCS412 PACKAGE TYPES PDIP, SOIC S2/RFEN/LC1 ...
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... When used as a code hopping encoder, the HCS412 is ideally suited to keyless entry systems; vehicle and garage door access in particular. The same HCS412 can also be used as a secure bi-directional transponder for contactless token verification ...
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... The transcoder portion of a passive entry sys- tem is integrated into a transmitter, carried by the user and operated to gain access to a vehicle or restricted area. The HCS412 is meant cost-effective yet secure solution to such systems, requiring very few external components (Figure 2-6). 1.1.1 ...
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... HCS412 2.0 DEVICE DESCRIPTION 2.1 Pinout Description The HCS412’s footprint is identical to other encoders in the K L family, except for the two pins reserved for EE OQ low frequency communication. TABLE 2-1: PINOUT SUMMARY Pin Pin Name Number S0 1 Button input pin with Schmitt Trigger detector and internal 60 k (nominal) pull-down resistor (Figure 2-1) ...
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... LED 2 7 LC1 DATA 3 6 GND LC0 LED 2 7 LC1 DATA 3 6 LC0 GND LED 2 7 DATA 3 6 LC0 GND 4 5 Preliminary HCS412 LED PIN DIAGRAM LED R > DS41099C-page 5 ...
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... If the design is to run on 5V, tune the oscillator while supplying the HCS412 with 5V. Say the HCS412’s oscillator is tuned to be optimal supply voltage but the device will operate on a sin- gle lithium battery. The resulting oscillator variance over temperature and voltage will not be ± ...
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... S2 BUTTON INPUT CONSIDERATIONS The S2/RFEN/LC1 pin defaults to LF antenna output LC1 when the HCS412 is first connected to the supply voltage (i.e., battery replacement). The configuration register controlling the pin’s function is loaded on the first device activation after battery replacement. A desired S2 input state is therefore enabled only after the first activation of either S0 LC0 ...
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... The button input states, cumulatively called the button status, determine whether the HCS412 transmits a code hopping or seed transmission, Table 3-1. Additional button activations added during a transmis- sion will immediately RESET the HCS412, perhaps leaving the current code word incomplete ...
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... Note 1: The transmitted button status will reflect the state of the LC0 input when the button inputs are sampled. 3.2 Transmitted Code Word The HCS412 transmits a 69-bit code word in response to a button or proximity activation (Figure 3-1). Each code word contains a 50% duty cycle preamble, ...
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... HCS412 FIGURE 3-2: CODE WORD ORGANIZATION 28-bit Serial Number (XSER = 0) Fixed Code Portion (37 Bits) CRC QUE V BUT SER 1 LOW 2 Bits 2 Bits 1-Bit 4 Bits 12 MSb’ MSb LC0 32-bit Serial Number (XSER = 1) Fixed Code Portion (37 Bits) CRC QUE SER 1 V LOW ...
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... The low voltage detector result is included in every transmitted code word. The HCS412 samples the voltage detector output at the onset of a transmission and just before the VLOW bit is transmitted in each code word. The first sample is used in the CRC calculation and the subsequent sam- ples determine what VLOW value will be transmitted. The transmitted VLOW status will be a ‘ ...
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... HCS412 FIGURE 3-4: SEED CODE WORD DATA FORMAT QUE CRC V BUT 2 Bits 2 Bits LOW 1-Bit 4 Bits 12 Most Sig Bits MSb LC0 Shaded data included in CRC calculation Note: SEED transmissions only allowed when appropriate configuration bits are set. TABLE 3-4: SEED TRANSMISSION OPTIONS ...
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... For FCC approval purposes, it may therefore be advantageous to minimize the transmis- sion duty cycle. This can be achieved by minimizing the on-time of the individual bits as well as by blanking out consecutive code words. Preliminary HCS412 Encrypt Fixed Code Guard Portion Time Sync ...
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... DELAYED INCREMENT (DINC) The HCS412’s Delayed Increment feature advances the synchronization counter period of T the encoder activation occurs, for additional security. The next activation will show a synchronization counter increase of 13, not 1. If the active button is released before the time-out T has elapsed, the device stops transmitting but remains powered for the duration of the time-out period ...
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... Microchip Technology Inc. Code Word Code Word Code Word Code Word Code Word Code Word Code Word Code Word T LEDOFF Code Word Code Word T LEDL T LPRE Second Code Word Third Code Word - Normal Preamble - Normal Preamble Preliminary HCS412 Header DS41099C-page 15 ...
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... If the PLL Interface option is set to FSK, the DATA pin will go high and the RFEN output will go low while the LED pin is low. If the bat- tery is low, the HCS412 transmits only until the LED goes on. • If the Temporary Seed (TMPSD) option is ...
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... LEDON T 480 LEDOFF T 200 LEDL T 3 DSD T 30 QUE > V specified the configuration word. DD TRIP LOW in the configuration word. LOW Preliminary HCS412 Max. Unit Remarks 63 + Code ms Note 1 Word Time 40 ms Note Note Note 4 ms Note 4 ms ...
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... HCS412 4.0 TRANSPONDER OPERATION 4.1 IFF Mode The HCS412’s IFF Mode allows it to function as a bi- directional token or transponder. IFF mode capabilities include the following. • A bi-directional challenge and response sequence for IFF validation. HCS412 IFF responses may be directed to use one of two available encryption algorithms and one of two available crypt keys. • ...
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... RF Comms (DATA) Field Ack sequence repeats every 255 LF Inductive Comms (LC) 255LF RF Comms (DATA) Communication from reader to HCS412 Filed ACK Sequence from HCS412 to reader FIGURE 4-2: LC PIN PULSE POSITION MODULATION (PPM) Transponder reader communication to the HCS412 Start or previous T bit ...
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... HCS412 4.3 IFF Commands TABLE 4-2: LIST OF AVAILABLE IFF COMMANDS Opcode Anticollision Command (Section 4.3.1) 00000 Select HCS412, used if Anticollision enabled Read Commands (Section 4.3.2) 00001 Read configuration word 00010 Read low serial number (least significant 16 bits) 00011 Read high serial number (most significant 16 bits) ...
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... Enabling anticollision allows addressing of an individual token, regardless how many tokens are in the field. The HCS412 method is that all tokens trained to a given vehicle will have the same 25 MSb’s of their serial number. The serial numbers tokens trained to access a given vehicle will differ only in the 3 LSb’ ...
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... The transponder reader sends one of seven possible write commands (Table 4-5) indicating which 16-bit EEPROM word to write to. The 16-bit data to be written follows the command. The HCS412 will attempt to write the value into EEPROM and respond with an Acknowl- edge sequence if successful. The following locations are available to write: • ...
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... ATO T PU ACK Start Communication from reader to HCS412 Communication from HCS412 to reader 2002 Microchip Technology Inc. Expected data In 28-bit Transport code; 16-Bit configuration word 28-bit Transport code; Least Significant 16 bits of the serial number (SER0) 28-bit Transport code; Most Significant 16 bits of the serial number (SER1) ...
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... HCS412 4.3.4 BULK ERASE A Bulk Erase resets the HCS412’s memory map to all zeros. The transponder reader selects the appropriate device through anticollision, as need be, issues the PROGRAM command followed by the device’s 28-bit transport code, then resets the device by removing the field for 100 ms. ...
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... The command is followed by the 32-bit challenge, typi- cally a random number. The HCS412 encrypts the challenge using the designated crypt key and algorithm and responds with the 32-bit encrypted result. The reader authenticates the response by comparing it to the expected value ...
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... Communication from reader to HCS412 Communication from HCS412 to reader 4.3.7 CODE HOPPING REQUEST The command tells the HCS412 to increment the syn- chronization counter and build the 32-bit code hopping portion of the code word. • Echo is disabled, the data will be transmitted on the LC lines only (Figure 4-12). ...
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... HCS412 does not receive a command before the sec- ond field Acknowledge sequence [within 255 LFT will transmit a normal code hopping transmission for 2 seconds on the DATA pin. After 2 seconds the HCS412 reverts to normal transponder mode. The 2 second transmission does not repeat when the device is in the presence of a continuous LF field ...
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... HCS412 4.4.2 ANTICOLLISION AND RF ECHO (LFSP = 11) In addition to enabling anticollision, this mode adds that all HCS412 responses and Acknowledges are echoed on the DATA output line. Responses are first transmit- ted on the DATA line, followed by the equivalent data transmitted on the LF LC lines Figure 4-17). ...
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... HCS412 will continue to resonate after a strong LF field is removed, slowly decaying. The slow decay makes fast communication near the reader difficult as data bit low times disappear. If the Intelligent Damping option is enabled, the HCS412 will clamp the LC pins through resistor for 5 s every 1 whenever the HCS412 is TE expecting data from the transponder reader ...
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... HCS412 5.0 CONFIGURATION SUMMARY Table 5-1 summarizes the available HCS412 options. TABLE 5-1: HCS412 CONFIGURATION SUMMARY Reference Symbol Section KEY1 64-bit Encoder Key 1 SDVAL Section 3.2.7 60-bit seed value transmitted in CH Mode if (SEED = 1 AND TMPSD = (SEED = 0 AND TMPSD = 1). KEY2 LSB 60 bits of Encoder Key 2. 4 MSb’s set to XXXX. (Note 1) TCODE Section 4 ...
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... INTEGRATING THE HCS412 INTO A SYSTEM Use of the HCS412 in a system requires a compatible decoder. This decoder is typically a microcontroller with compatible firmware. Microchip will provide (via a free license agreement) firmware routines that accept transmissions from the HCS412 and decrypt the hopping code portion of the data stream. These routines provide system designers the means to develop their own decoding system ...
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... HCS412 6.2 Decoder Operation Figure 6-2 summarizes normal decoder operation. The decoder waits until a transmission is received. The received serial number is compared to the EEPROM table of learned transmitters to first determine if this transmitter’s use is allowed in the system. If from a learned transmitter, the transmission is decrypted using the stored crypt key and authenticated via the discrimination bits for appropriate crypt key usage ...
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... Codes) Stored Synchronization Counter Value Double Operation (resynchronization) Single Operation Window Window (32K Codes) (16 Codes) EEPROM Array Manufacturer Code 32 Bits of Encrypted Data Decryption Algorithm Decrypted Synchronization 4 Counter Preliminary HCS412 Serial Number Sync Counter Crypt Key Check for Match DS41099C-page 33 ...
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... (Clock) Note Verify operation done, then it must immediately follow the Program cycle. DS41099C-page 34 The HCS412 will signal a ‘write complete’ after writing each 16-bit word by sending out a series of ACK pulses T high, T ACKH ACKL tinue until S2 is dropped. ...
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... EEPROM Organization TABLE 7-1: HCS412 EEPROM ORGANIZATION 16Bit Word KEY1_1 2 KEY1_3 3 KEY1_5 4 KEY1_7 (KEY1 MSB) 5 SEED_1 / KEY2_1 6 SEED_3 / KEY2_3 7 SEED_5 / KEY2_5 / TCODE_1 8 TCODE_3 (MSB for all 3) RFBSL OVR SER1 12 SER3 13 USR0 MSB 14 USR1 MSB ...
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... HCS412 8.0 ELECTRICAL CHARACTERISTICS TABLE 8-1: ABSOLUTE MAXIMUM RATING Symbol V Supply voltage Input voltage IN V Output voltage OUT I Max output current OUT T Storage temperature STG T Lead soldering temp LSOL V ESD rating (Human Body Model) ESD Note: Stresses above those listed under “ABSOLUTE MAXIMUM RATINGS” may cause permanent damage to the device ...
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... A1 .015 E .300 .313 .325 E1 .240 .250 .260 D .360 .373 .385 L .125 .130 .135 c .008 .012 .015 B1 .045 .058 .070 B .014 .018 .022 § eB .310 .370 .430 Preliminary HCS412 MILLIMETERS MIN NOM MAX 8 2.54 3.56 3.94 4.32 2.92 3.30 3.68 0.38 7.62 7.94 8.26 6.10 6.35 6.60 9.14 9.46 9.78 3.18 3.30 3.43 0.20 0.29 0.38 1.14 1.46 1.78 0.36 0.46 0.56 7.87 9.40 10. ...
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... HCS412 Package Type: 8-Lead Plastic Small Outline (SN) – Narrow, 150 mil (SOIC Dimension Limits Number of Pins Pitch Overall Height Molded Package Thickness Standoff § Overall Width Molded Package Width Overall Length Chamfer Distance Foot Length Foot Angle Lead Thickness ...
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... Standard marking consists of Microchip part number, year code, week code and traceability code. For marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For SQTP devices, any special marking adders are included in SQTP price. 2002 Microchip Technology Inc. Example HCS412 XXXXX862 9925 Example XXXXXXXX XXXX9925 862 Preliminary HCS412 DS41099C-page 39 ...
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... HCS412 ON-LINE SUPPORT Microchip provides on-line support on the Microchip World Wide Web (WWW) site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Explorer ...
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... Is there any incorrect or misleading information (what and where)? 7. How would you improve this document? 8. How would you improve our software, systems, and silicon products? 2002 Microchip Technology Inc. Total Pages Sent FAX: (______) _________ - _________ N Literature Number: DS41099C Preliminary HCS412 DS41099C-page 41 ...
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... HCS412 10.0 HCS412 PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office. HCS412 — /X Package: Temperature Range: Device: Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recom- mended workarounds ...
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... Use of Microchip’s products as critical com- ponents in life support systems is not authorized except with express written approval by Microchip. No licenses are con- veyed, implicitly or otherwise, under any intellectual property rights. 2002 Microchip Technology Inc. Trademarks The Microchip name and logo, the Microchip logo, FilterLab ...
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... Centro Direzionale Colleoni Palazzo Taurus Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 03/01/02 2002 Microchip Technology Inc. ...