HCS410_11 Datasheet, PDF (20/46 Pages) Microchip Technology – KEELOQ® Code Hopping Encoder and Transponder 2-bit CRC, 2-bit queue

HCS410
3.7 Configuration Data
The configuration data is used to select various
encoder options. Further explanations of each of the
bits are described in the following sections.
TABLE 3-1: CONFIGURATION OPTIONS
SEED
Symbol
Description
CWBE
IDAMP
SEED/
IFF2
Code Word Blanking Enable
Intelligent Damping for High Q LC Tank.
Enable Seed Transmissions
TMPSD/
IFF2
OSC0:3
MTX3
VLOW
LED
Temporary Seed Transmissions
Onboard Oscillator Tuning Bits
Minimum 3 Code Words Transmitted
Low Voltage Trip Point Selection
Enable LED output
BSL0:1
TBSL
MANCH
ACOLI
XPRF
DINC
XSER
Baudrate Select
Transponder Baud Rate
Manchester Modulation Mode
Anti Collision Communication Enable
Passive Proximity Activation
Delayed Increment Enable
Extended Serial Number
3.7.1 CWBE: CODE WORD BLANKING ENABLE
BSL: BAUD RATE SELECT
Selecting this option allows code blanking as shown in
Table 3-3. If this option is not selected, all code words
are transmitted.
3.7.2 IDAMP: INTELLIGENT DAMPING
If IDAMP is set to ‘1’ intelligent damping is disabled.
3.7.3 SEED, TMPSD: SEED TRANSMISSION
SEED
0
0
1
1
TMPSD
0
1
0
1
Description
No Seed/1 IFF Key
Seed Limited*
Always Enabled
IFF2/No Seed/2
IFF Keys
* Seed transmissions are allowed till the sychroniza-
tion counter crosses a XX7F₁₆ boundary. e.g. If the
counter is initialized to 0000₁₆ when the device is
programmed, seed transmissions will be allowed
until the counter wraps from 007F₁₆ to 0080₁₆ giving
the user 127 transmissions before seed transmis-
sions are disabled.
3.7.4 OSC: OSCILLATOR TUNING BITS
These bits allow the onboard oscillator to be tuned to
within 10% of the nominal oscillator speed over both
temperature and voltage.
TABLE 3-2: OSCILLATOR TUNING
OSC
Description
1000
1001
1010
•
•
•
1111
0000
0001
0010
•
•
•
0110
0111
Fastest
Faster
Nominal
Slower
Slowest
TABLE 3-3: BAUD RATE SELECTION
Code Hopping Transmissions (TE)
Transponder Communication (TE)
BSL 1
BSL 0
PWM
Manchester
Codes Word
Transmitted*
TBSL
PPM
0
0
400 μs
800 μs
All
0
0
1
200 μs
400 μs
1 of 2
—
1
0
100 μs
200 μs
1 of 2
—
1
1
100 μs
200 μs
1 of 4
1
Note: *If code word blanking is enabled.
200 μs
—
—
100 μs
DS40158F-page 20
© 2011 Microchip Technology Inc.