HCS300-IP Microchip Technology, HCS300-IP Datasheet
HCS300-IP
Related parts for HCS300-IP
HCS300-IP Summary of contents
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... The encryption key, serial number, and configuration data are stored in EEPROM which is not accessible via any external connection. This makes the HCS300 a very secure unit. The HCS300 provides an easy to use serial interface for programming the necessary security keys, system parameters, and confi ...
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... Transmission of the random seed can be dis- abled after learning is completed. The HCS300 is a code hopping encoder device that is designed specifically for keyless entry systems, primarily for vehicles and home garage door openers. It ...
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... Any type of controller may be used as a receiver, but it is typically a microcontroller with compatible firmware that allows the receiver to operate in conjunction with a transmitter, based on the HCS300. Section 7.0 provides more detail on integrating the HCS300 into a total system. Before a transmitter can be used with a particular receiver, the transmitter must be ‘learned’ by the receiver ...
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... PWM 6 Tx out LED The high security level of the HCS300 is based on the patented encryption algorithm based on a block length of 32 bits and a key length of 64 bits is used. The algorithm obscures the information in such a way that even if the ...
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... Stop 1996 Microchip Technology Inc. 3.0 EEPROM MEMORY ORGANIZATION The HCS300 contains 192 bits (12 x 16-bit words) of EEPROM memory (Table 3-1). This EEPROM array is used to store the encryption key information, synchronization value, etc. Further descriptions of the memory array is given in the following sections. TABLE 3-1: ...
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... HCS300 3.2 SYNC (Synchronization Counter) This is the 16-bit synchronization value that is used to create the hopping code for transmission. This value will be changed after every transmission. 3.3 SER_0, SER_1 (Encoder Serial Number) SER_0 and SER_1 are the lower and upper words of the device serial number, respectively. Although there are 32 bits allocated for the serial number, only the lower order 28 bits are transmitted ...
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... should not be toggled until all internal processing has been com- pleted as shown in Figure 4-4. 4.3 Code Word Organization The HCS300 transmits a 66-bit code word when a but- V LOW ton is pressed. The 66-bit word is constructed from a Fixed Code portion and an Encrypted Code portion (Figure 4-2) ...
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... HCS300 FIGURE 4-1: CODE WORD TRANSMISSION FORMAT LOGIC ‘0’ LOGIC ‘1’ Bit Period Preamble T P FIGURE 4-2: CODE WORD ORGANIZATION Fixed Code Data VLOW and Button Repeat Status 28-bit Serial Number Status (2 bits) (4 bits) Serial Number and Button 2 bits + Status (32 bits) ...
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... In order to increase the level of security in a system possible for the receiver to implement what is known as a secure learn function. This can be done by utilizing the seed value on the HCS300 which is stored in EEPROM and can only be transmitted when all four button inputs are pressed at the same time (Table 5-1). Instead of the ...
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... HCS300 FIGURE 5-1: BLANK ALTERNATE CODE WORD (BACW) Amplitude BACW Disabled A (All words transmitted) BACW Enabled 2A (1 out of 2 transmitted) BACW Enabled 4A (1 out of 4 transmitted) 5.6 VLOW: Voltage LOW Indicator The VLOW bit is transmitted with every transmission (Figure 8-4) and will be transmitted as a one if the operating voltage has dropped below the low voltage trip point ...
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... PROGRAMMING THE HCS300 When using the HCS300 in a system, the user will have to program some parameters into the device including the serial number and the secret key before it can be used. The programming cycle allows the user to input all 192 bits in a serial data stream, which are then stored internally in EEPROM ...
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... HCS300 TABLE 6-1: PROGRAMMING/VERIFY TIMING REQUIREMENTS V = 5.0V 10 Parameter Symbol Program mode setup time Hold time 1 Hold time 2 Bulk Write time Program delay time T Program cycle time Clock low time Clock high time T Data setup time Data hold time Data out valid time DS21137D-page 12 Min ...
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... INTEGRATING THE HCS300 INTO A SYSTEM Use of the HCS300 in a system requires a compatible decoder. This decoder is typically a microcontroller with compatible firmware. Microchip will provide (via a license agreement) firmware routines that accept transmissions from the HCS300 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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... HCS300 7.2 Decoder Operation In a typical decoder operation (Figure 7-2), the key gen- eration on the decoder side is done by taking the serial number from a transmission and combining that with the manufacturer’s code to create the same secret key that was used by the transmitter. Once the secret key is obtained, the rest of the transmission can be decrypted ...
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... Max 0.2 0.5 0.7 1.4 0.1 1.0 0.1 1 160 650 V +0.3 0.55V 0.15V -0.3 0.15V DD 0.7V DD 0.08V DD 0.08V 1.8 2.5 2.0 2.7 3 120 160 80 120 160 Preliminary HCS300 Units (Note) C (Note) V Unit Conditions 2.0V OL ...
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... HCS300 FIGURE 8-1: POWER UP AND TRANSMIT TIMING Button Press Detect PWM Sn TABLE 8-3: POWER UP AND TRANSMIT TIMING REQUIREMENTS V = +2.0 to 6.3V DD Commercial (C): Tamb = +70 C Industrial (I): Tamb = - +85 C Parameter Time to second button press Transmit delay from button detect Debounce delay Auto-shutoff time-out period Note the time in which a second button can be pressed without completion of the fi ...
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... HOP T Fixed code duration 102 FIX T Guard Time G Total Transmit Time 270 PWM data rate Note: The timing parameters are not tested but derived from the oscillator clock. FIGURE 8-5: HCS300 TE VS. TEMP 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 -50 -40 -30 -20 - 1996 Microchip Technology Inc. ...
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... HCS300 NOTES: DS21137D-page 18 Preliminary 1996 Microchip Technology Inc. ...
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... HCS300 Product Identification System To order or to obtain information (e.g., on pricing or delivery), please use the listed part numbers, and refer to the factory or the listed sales offices. HCS300 - /P Package: Temperature Range: Device: Sales and Support Products supported by a preliminary Data Sheet may possibly have an errata sheet describing minor operational differences and recommended workarounds ...
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... Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. No repre- sentation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip’s products as critical components in life support systems is not autho- rized except with express written approval by Microchip ...