HCS515/SL Microchip Technology, HCS515/SL Datasheet - Page 12

• Manufacturer Part Number: HCS515/SL
• Description: IC CODE HOPPING DECODER 14-SOIC
• Manufacturer: Microchip Technology
• Type: Code Hopping Decoderr

Specifications of HCS515/SL

• Applications: Remote Secure Access, Keyless Entry
• Mounting Type: Surface Mount
• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Ic Function: Code Hopping Decoder IC
• Supply Voltage Range: 4.5V To 5.5V
• Operating Temperature Range: 0°C To +70°C
• Digital Ic Case Style: SOIC
• No. Of Pins: 14
• Termination Type: SMD
• Filter Terminals: SMD
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: HCS515/SLR; HCS515/SLR

ecoder DATA
HCS515
4.2.7
The erase all command (Figure 4-6) erases all the
transmitters in the decoder. After the command and two
dummy bytes are clocked in, the clock line must be
FIGURE 4-6:
4.2.8
The activate learn command (Figure 4-7) is used to
activate a transmitter learning sequence on the
decoder. The command consists of a Command mode
activation sequence, a command byte, and two dummy
bytes. The decoder will respond by taking the data line
high to acknowledge that the command was valid and
that learn is active.
Upon reception of the first transmission, the decoder
will respond with a learn status message (Figure 4-8).
During learn, the decoder will acknowledge the recep-
tion of the first transmission by taking the data line high
for 60 ms. The controlling microcontroller can clock out
at most 8 bits, which will all be zeros. All of the bits of
the status byte are zero, and this is used to distinguish
between a learn time-out status string and the first
transmission received string. The controlling microcon-
troller must ensure that the clock line does not go high
60 ms after the falling edge of the data line, for this will
terminate learn.
FIGURE 4-7:
DS40183D-page 12
C DATA
Decoder DATA
CLK
C DATA
A
START Command
ERASE ALL
CLK
ACTIVATE LEARN
A
START Command
ERASE ALL
LEARN MODE ACTIVATION
B
LSB
B
LSB
Command Byte
Command Byte
MSB
MSB
C
LSB
C
LSB
Dummy Byte
Subcommand Byte
MSB
MSB
asserted to activate the command. After a successful
completion of an erase all command, the data line is
asserted until the clock line goes low.
Upon reception of the second transmission, the
decoder will respond with a learn status message
(Figure 4-9).
The learn status message after the second transmis-
sion consists of the following:
• 1 START bit.
• The function code [
• The RESULT bit indicates the result of the learn
• The OVR bit will indicate whether an exiting trans-
• The [
• The [
zero, indicating that this is a status string.
sequence. The RESULT bit is set if successful
and cleared otherwise.
mitter is over written. The OVR bit will be set if an
existing transmitter is learned over.
transmitters learned on the decoder.
used during the learning of the transmitter.
D
LSB
D
CNT3…CNT0
TX3…TX0
LSB
Dummy Byte
Dummy Byte
] bits indicate the block number
MSB
MSB
] bits will indicate the number of
T
S3:S0
T
LRN
ERA
E
2002 Microchip Technology Inc.
E
] of the message is
T
Acknowledge
ACK
T
Acknowledge
ACK
T
T
T
RESP
ACK
RESP
T
ACK
2
2
F
F