TI TRC1300

TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
D
D
D
D
D
D
Devices can be Configured as an Encoder
or a Decoder
Hopping 40-Bit Security Code† (More Than
1 Trillion Combinations) and
Transmitter-Lock Provide Extremely High
Security
Four Independent Inputs/Outputs Allow For
Control of Up To 15 Functions
Internal EEPROM and Programming Charge
Pump
No Programming Station Required –
Self-Programming Encoder
Smart Decoder Learns Up To Four Different
Encoders
D
D
D
D
Adjustable Internal Clock Provides Wide
Range of Data-Rate Speeds
Internal Amplifier and Comparator for
Amplification and Shaping of Low-Level
Input Signals With Autobias Adaptive
Threshold Circuitry using
Switched-Capacitor Technology
Minimum Number of Required External
Components and Surface-Mount Packaging
for Extremely Small Circuit Footprint
Advanced CMOS Processing Technology
for Minimum Power Consumption and 2.7-V
to 15 -V Operation
D PACKAGE
(TOP VIEW)
DIN/DOUT
CONF
PROG
LED
OSCC
OSCR
GND
1
2
3
4
5
6
7
14
13
12
11
10
9
8
N PACKAGE
(TOP VIEW)
VCC/CAP
VCC
TEST
VRC/TX4
VRC/TX3
VRC/TX2
VRC/TX1
DIN/DOUT
CONF
PROG
LED
OSCC
NC
OSCR
GND
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC/CAP
VCC
TEST
VRC/TX4
VRC/TX3
NC
VRC/TX2
VRC/TX1
NC – No internal connection
description
The TRC1300 and TRC1315 are remote control serial-data encoders and decoders, and are members of the
MARCSTAR (Multichannel Advanced Remote Control Serial Transmitter and Receiver) family of remote
control serial-data devices. Each can be configured to perform as either the encoder or the decoder in a remote
control system. The TRC1300 and TRC1315 are designed for use in high-volume remote control products such
as automobile and home security systems, consumer electronics, electronic keys, and remote keyless entry
applications. They are low-power devices and are well suited to battery operation with a supply voltage of 2.7 V
to 6 V for the TRC1300 and 2.7 V to 15 V for the TRC1315.
Four independent encoder inputs/decoder outputs allow for control of up to 15 functions. Forty bits of hopping
code provide high security, more than one trillion possible combinations, so that the same code will never be
used twice by a MARCSTAR device over several lifetimes of a typical system. The MARCSTAR devices are
self-programming with internal charge-pump programming circuitry. A smart decoder design learns up to four
different encoders, all in a high-security hopping-code format.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
MARCSTAR and Transmitter-Lock are trademarks of Texas Instruments Incorporated.
† The coding algorithm and other MARCSTAR functionality are patented or are patent pending.
Copyright  1997, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
description (continued)
The TRC1300 and TRC1315 include several on-chip functions that normally require additional circuitry in a
system design. These include an amplifier/comparator for detection and shaping of input signals as low as a
few millivolts (typically when an RF link is used) and a variable-frequency internal oscillator to clock the
transmitted or received security code.
The TRC1300 and TRC1315 MARCSTAR I E/D remote control encoder/decoders are characterized for
operation over the temperature range of – 40°C to 85°C and are available in 14-pin SOIC small-outline IC
surface-mount (D) and 16-pin PDIP plastic dual in-line (N) packages.
functional block diagram
VCC
13
VCC/CAP
14
OSCC
5
OSCR
6
Mux
Voltage Regulator
(TRC1315 Only)
8
Clock/
Oscillator
9
Mux
DIN/DOUT 1
Input Buffer
Amplifier/Comparator
Shift
Register
Decoder
Logic
10
11
VRC/TX1
VRC/TX2
VRC/TX3
VRC/TX4
CONF 2
LED 4
TEST 12
Configuration
Logic
Encoder Logic
EEPROM Memory Cells
(192 bits)
4 Banks of 40 Security Bits
and 8 Check-Sum Bits
7
GND
NOTE A: Terminal numbers are for the D package.
2
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• DALLAS, TEXAS 75265
Programming
Logic
(with charge pump)
3
PROG
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
Terminal Functions
TERMINAL
NO.
I/O
DESCRIPTION
2
I
Device configuration select. When CONF is held at a high logic level, the device assumes the encoder
mode. CONF is internally pulled up, and no connection to CONF is required for the encoder mode of
operation. When CONF is held at a low logic level at power up, the device assumes the decoder mode.
Note that this terminal is read only at device power up; CONF must be tied to GND before VCC is applied
to select the decoder mode.
1
1
I/O
Serial data input/output. In the decoder mode, DIN/DOUT becomes an input to receive serial data from
up to four remote encoders. In the learn mode, DIN/DOUT becomes an input to learn code from up
to four remote encoders. In the encoder mode, DIN/DOUT becomes an output for the encoded data.
DIN/DOUT is clocked by the internal variable oscillator.
GND
7
8
LED
4
4
NAME
D
N
CONF
2
DIN/DOUT
Analog and logic ground
O
Status indicator. The LED terminal goes low, causing an LED connected from VCC (anode) to the LED
terminal (cathode) through a current-limiting resistor to light, indicating the following conditions:
•
Encoder mode. When the device is configured as an encoder, the LED terminal is active during
the transmission of data (including the blank time between frames).
•
Program mode (encoder). When the device is configured as an encoder and placed in the
program mode, the LED terminal is active until the device has generated and stored a new 40-bit
security code.
•
Learn mode (decoder). When the device is configured as a decoder and placed in the program
mode, the LED terminal is active until the device has successfully stored 40 bits of security code
received from an encoder through terminal DIN/DOUT.
•
Test mode. When the device is placed in the self-test mode, the results are indicated by flashing
the LED connected to the LED terminal.
OSCC
5
5
I/O
Internal oscillator frequency control. A capacitor connected from OSCC to GND and a resistor
connected from OSCR to OSCC determine the frequency of the internal oscillator.
OSCR
6
7
I/O
Internal oscillator frequency control. A resistor connected from OSCR to OSCC and a capacitor
connected from OSCC to GND determine the frequency of the internal oscillator.
PROG
3
3
I
Programming enable. When PROG is held at a logic-high, device enters the programming mode. In
the encoder mode, a new 40-bit security code is generated and stored in EEPROM. In the decoder
mode, the device enters a learn cycle that continues until it has successfully received 40 bits of code
from an encoder and stored them in EEPROM. PROG is internally pulled down and debounced.
TEST
12
14
I
Test mode select. When TEST is momentarily taken high, the device enters a self-test mode with the
results of the self-test mode displayed by flashing the LED connected to the LED terminal. TEST is
internally pulled down.
VCC
(TRC1300)
13
15
Not used.
VCC
(TRC1315)
13
15
Power supply input for the TRC1315 only. The voltage range for VCC is 4.5 V to 15 V. A 0.1-µF bypass
capacitor should be connected from VCC to GND.
VCC/CAP
(TRC1300)
14
16
Power supply input for the TRC1300 only. The voltage range for VCC/CAP is 2.7 V to 6 V. A 0.1-µF
bypass capacitor should be connected from VCC/CAP to GND.
VCC/CAP
(TRC1315)
14
16
Regulated voltage output for the TRC1315 only. This terminal provides a regulated 4.5 V to 5.5 V
output. A 1-µF and a 0.1-µF bypass capacitor should be connected from VCC/CAP to GND.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
Terminal Functions
TERMINAL
NO.
I/O
DESCRIPTION
9
I/O
Function 1 VRC (valid received code) output and function 1 encode enable. In the decode mode,
VRC/TX1 is an output that goes to a logic-low state (for one frame — 768 clocks) when the device
receives the correct 40 bits of security code and function data (4 bits) matching function 1. In the
encoder mode, VRC/TX1 is an input that initiates the encoding of function 1 and output of function 1
data. When VRC/TX1 is pulled to GND, the device continuously outputs the function-1 code sequence
stored in EEPROM memory from DIN/DOUT up to 360 times. The device cannot transmit function-1
code again until VRC/TX1 is again pulled to GND. VRC/TX1 has an internal pullup resistor in both the
encoder and decoder modes, and switch debouncing in the encoder mode.
9
10
I/O
Function 2 VRC (valid received code) output and function 2 encode enable. In the decode mode,
VRC/TX2 is an output that goes to a logic-low state (for one frame — 768 clocks) when the device
receives the correct 40 bits of security code and function data (4 bits) matching function 2. In the
encoder mode, VRC/TX2 is an input that initiates the encoding of function 2 and output of function 2
data. When VRC/TX2 is pulled to GND, the device continuously outputs the function-2 code sequence
stored in EEPROM memory from DIN/DOUT up to 360 times. The device cannot transmit function-2
code again until VRC/TX2 is again pulled to GND. VRC/TX2 has an internal pullup resistor in both the
encoder and decoder modes, and switch debouncing in the encoder mode.
VRC/TX3
10
12
I/O
Function 3 VRC (valid received code) output and function 3 encode enable. In the decode mode,
VRC/TX3 is an output that goes to a logic-low state (for one frame — 768 clocks) when the device
receives the correct 40 bits of security code and function data (4 bits) matching function 3. In the
encoder mode, VRC/TX3 is an input that initiates the encoding of function 3 and output of function 3
data. When VRC/TX3 is pulled to GND, the device continuously outputs the function-3 code sequence
stored in EEPROM memory from DIN/DOUT up to 360 times. The device cannot transmit function-3
code again until VRC/TX3 is again pulled to GND. VRC/TX3 has an internal pullup resistor in both the
encoder and decoder modes, and switch debouncing in the encoder mode.
VRC/TX4
11
13
I/O
Function 4 VRC (valid received code) output and function 4 encode enable. In the decode mode,
VRC/TX4 is an output that goes to a logic-low state (for one frame — 768 clocks) when the device
receives the correct 40 bits of security code and function data (4 bits) matching function 4. In the
encoder mode, VRC/TX4 is an input that initiates the encoding of function 4 and output of function 4
data. When VRC/TX4 is pulled to GND, the device continuously outputs the function-4 code sequence
stored in EEPROM memory from DIN/DOUT up to 360 times. The device cannot transmit function-4
code again until VRC/TX4 is again pulled to GND. VRC/TX4 has an internal pullup resistor in both the
encoder and decoder modes, and switch debouncing in the encoder mode.
NAME
D
N
VRC/TX1
8
VRC/TX2
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, TRC1300, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.6 V to 7 V
TRC1315, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.6 V to 15 V
Input voltage, logic/analog signals, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.6 V to 7 V
Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 40°C to 85°C
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 65°C to 150°C
ESD protection, all terminals, human body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 kV
machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 V
JEDEC latchup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 mA or 13.2 V
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: Voltage values are with respect to GND.
4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
recommended operating conditions
encoder VCC
Supply voltage
voltage, device configured as an encoder,
Supply voltage,
voltage device configured as a decoder,
decoder VCC
MIN
MAX
TRC1300
2.7
6
TRC1315
2.7
15
TRC1300
4.5
6
TRC1315
4.5
15
Low-level input voltage, VIL, at VRC/TX1 – VRC/TX4, TEST, CONF, PROG
High-level input voltage, VIH, at VRC/TX1 – VRC/TX4, TEST, CONF, PROG
Operating free-air temperature, TA
Input voltage to amplifier/comparator, VI(PP), at DIN/DOUT
UNIT
V
V
0.5
VCC /CAP– 0.5
– 40
V
V
°C
85
10
Common-mode input voltage range, amplifier/comparator
mV
GND + 0.2
VCC /CAP– 0.2
V
electrical characteristics over recommended ranges of supply voltage and free-air temperature
(unless otherwise noted)
digital interface
PARAMETER
TEST CONDITIONS
VOL
Low-level output voltage
VRC/TX1 – VRC/TX4,
DIN/DOUT, LED
IOL = 5 mA
VOH
High-level output voltage
VRC/TX1 – VRC/TX4,
DIN/DOUT, LED
IOH = –4 mA
MIN
TYP
0.5
VCC /CAP– 0.5
CONF
VI = 0 to VIL
–20
–12
–5
–20
–11
–5
PROG
1
TEST
1
DIN/DOUT
5
High-level input current
CONF
µA
20
VRC/TX1 – VRC/TX4
IIH
V
1
VRC/TX1 – VRC/TX4
Low-level input current
UNIT
V
DIN/DOUT
IIL
MAX
1
VI = VIH to VCC/CAP
1
PROG
2
5
8
TEST
5
12
20
TYP
MAX
1.8
2.2
µA
decoder supply current, VCC/CAP = 6 V, TA = 25°C
PARAMETER
MIN
Supply current
UNIT
mA
encoder supply current, TRC1300, VCC/CAP= 6 V, TA = 25°C
TYP
MAX
UNIT
Supply current, standby
PARAMETER
MIN
35
500
nA
Supply current, code transmission
1.5
1.7
mA
TYP
MAX
3
µA
1.4
1.9
mA
encoder supply current, TRC1315, VCC = 15 V, TA = 25°C
PARAMETER
MIN
Supply current, standby
Supply current, code transmission
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
UNIT
5
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
regulated output source current, TRC1315, active state, decoder mode, TA = 25°C
PARAMETER
TEST CONDITIONS
Maximum current at VCC/CAP for 5 V ± 10% output
Maximum current at VCC/CAP for 5 V ± 10% output
MIN
TYP
VCC = 6.4 V
VCC = 12 V
MAX
UNIT
8
mA
30
mA
oscillator characteristics
PARAMETER
TEST CONDITIONS
MIN
MAX
5
50
kHz
500
5 000
Hz
Sample-clock frequency, f(SCLK)
Data-clock frequency, f(DCLK)
(temperature VCC) using external capacitor
Frequency spread (temperature,
UNIT
± 7%
VCC/CAP 4 V – 6 V (decoder)
VCC/CAP 2.7 V – 6 V (encoder)
0.5 fRX†
Required encoder frequency accuracy for synchronization
† fRX is decoder frequency.
± 10%
2 fRX†
encoder self programming
PARAMETER
MIN
Minimum time for PROG low to generate a new 40-bit security code
MAX
UNIT
300
µs
EEPROM write/erase endurance
PARAMETER
Number of program cycles
MIN
TYP
100 000
1 000 000
MAX
UNIT
cycles
EEPROM data retention
PARAMETER
MIN
Data retention
TYP
MAX
10
UNIT
years
function switch input characteristics
PARAMETER
TEST CONDITION
Pulldown current at DIN/DOUT,
DIN/DOUT PROG,
PROG TEST
Pulldown resistor value at DIN/DOUT,
DIN/DOUT PROG,
PROG TEST
TX1 TX4 CONF,
CONF LED
Pullup current at TX1–TX4,
Pullup resistor value at TX1
TX1–TX4,
TX4 CONF
CONF, LED
6
TYP
MAX
UNIT
7.7
µA
4.8
µA
VCC/CAP = 3 V
VCC/CAP = 2.4 V
2.3
µA
1.3
µA
VCC/CAP = 5 V
VCC/CAP = 4 V
649
kΩ
833
kΩ
1304
kΩ
VCC/CAP = 3 V
VCC/CAP = 2.4 V
1846
kΩ
VCC/CAP = 5 V
VCC/CAP = 4 V
7.7
µA
4.8
µA
VCC/CAP = 3 V
VCC/CAP = 2.4 V
2.4
µA
1.3
µA
VCC/CAP = 5 V
VCC/CAP = 4 V
649
kΩ
VCC/CAP = 3 V
VCC/CAP = 2.4 V
POST OFFICE BOX 655303
MIN
VCC/CAP = 5 V
VCC/CAP = 4 V
• DALLAS, TEXAS 75265
833
kΩ
1250
kΩ
1846
kΩ
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
switching characteristics over recommended ranges of supply voltage and free-air temperature
(see Figure 1)
PARAMETER
tc
tc(0)
MIN
Cycle time of sample clock (SCLK)
Oscillating period
20
Cycle time of data clock (DCLK)
Oscillating period
200
TYP
MAX
UNIT
200
µs
2000
µs
Cycle time of logic-0 symbol
3 tc
µs
tc(1)
Cycle time of logic-1 symbol
tc(sync) Cycle time of sync pulse
3 tc
µs
2 tc
µs
tc
µs
tw
Pulse duration of dummy pulse
PARAMETER MEASUREMENT INFORMATION
SCLK
DCLK = SCLK ÷ 10
tc
DCLK
tc(sync)
tc(1)
tc(0)
tw
VIH
DOUT
VIL
Figure 1. Timing Diagram
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TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
general
Operation of the MARCSTAR I E/D devices is shown in Figure 2. The devices have two primary modes of
operation: encoder mode and decoder mode. Additional modes and functions include programming and
learning mode, self-testing mode, security code generation, and clock generation.
Power-On Reset
Low (Decoder Mode)
TEST
†
Low
CONF
†
High
High
Test Mode
TEST
†
Low
Low
PROG
†
High
Program (PROG)
Low
PROG
†
High
(PROG)
Decoder
Learn Path
LED On
Learn Code
LED Off
High (Encoder Mode)
Encoder
Path
Normal
Decode Path
Flag
Low
High
Attempting To Retransmit
Received-Code Path
Store a New Code
LED On (2 s)
Set Flag High
Reset Flag
PROG
†
Low
Normal Encode Path
High
Decoder Mode
Encoder Mode
Figure 2. Top Level Operational Flow
8
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† = Terminals
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
general (continued)
Each of the TRC1300 and TRC1315 MARCSTAR I E/D devices can be pin-selected for operation as either an
encoder on the transmitter end of a remote control system, or as a decoder on the receiver end. The intervening
medium can be a wired, RF, IR, or any other type of link with sufficient bandwidth to pass the signal. The objective
is to transmit a function code to the remote receiver to initiate an event or for some other purpose, with the
highest level of certainty that the function code is only accepted from the matching encoder and not from any
other.
A MARCSTAR I E/D device operating in the encoder mode can send four different function codes either
individually or in any combination to activate up to 15 different functions at the decoder.
Once a decoder learns a security code from an encoder, it then responds only to that particular encoder. A
MARCSTAR I E/D device operating in the decoder mode can learn and respond to as many as four different
encoders and provides four independent function outputs. These outputs can be further decoded (externally)
to provide a 1-of-15 function output.
hopping code
The MARCSTAR I E/D devices use an advanced hopping-code algorithm to significantly increase the security
level of the system. The security code sent by the encoder and the security code accepted as valid by the
decoder change after each transmission. This is done independently for each of the four separate encoder
security codes learned by the decoder.
As an encoder, the MARCSTAR I E/D is shipped from the factory with a unique 40-bit security code stored in
on-board nonvolatile memory (EEPROM). Since every device shipped has a unique code, it is ready for
immediate use and requires no reprogramming. Then, each time a function input is activated, the encoder
fetches the 40-bit security code from EEPROM and encrypts it. Next, the encoder assembles the data frame
to be output, and then sends it out. The data frame consists of the synchronizing bits, the encrypted security
bits, the function data bits, a dummy bit, and the blank-time bits. After the data frames output ends, the encoder
immediately increments the 40-bit security code by applying the special hopping-code algorithm to it and then
stores the results in EEPROM for the next time a function input is activated. Thus, each time a function input
is activated, the 40-bit security code that is sent out is different from the security code in the previous
transmission. And with more than a trillion possible combinations, the same code is never sent twice over the
lifetime of a system.
As a decoder, the MARCSTAR I E/D initially learns the 40-bit security code stored in a particular encoder by
receiving it and storing it in on-board EEPROM. Each time a security code is received from an encoder, the
device decrypts the received 40-bit security code and compares it with the next security code expected from
any of the learned encoders. The next expected security code is calculated by applying the same hopping-code
algorithm used in the encoder to the 40-bit code stored in the decoder memory. If the received security code
matches the next security code expected from one of the learned encoders, it is declared valid and the attached
function code is decoded. If the function code is valid, the appropriate function output or outputs are asserted.
The just-received 40-bit security code is then incremented according to the algorithm, becoming the next
security code expected from that encoder, and stored in EEPROM for next time. If the received security code
does not match the next expected code from one of the learned encoders, the received function data and
security code are ignored.
Because the decoder activates function outputs only when the next expected code in the hopping-code
sequence is received, interception and subsequent retransmission of the same code does not activate the
decoder function outputs.
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9
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
hopping code (continued)
In some cases, the encoder is activated and sends security and function data code without the decoder
receiving and decoding the signal (if the receiver is out of range, for example). This would normally cause the
encoder and decoder to fall out of sync with each other. MARCSTAR I E/D devices circumvent this by allowing
the decoder to activate the function outputs when any one of the next 256 expected security codes is received
from a learned encoder. The 256 expected security codes are based on the currently-stored 40-bit security
code. In rare cases, the encoder might be activated more than 256 times without being near the decoder,
requiring the encoder and decoder pair to be manually resynchronized. In this case, the decoder can simply
learn the current encoder security code, using the procedure detailed in the decoder programming section of
this document, resynchronizing the pair.
Hopping code provides extremely high security for the encoder/decoder pair and prevents unauthorized access
to the receiver and decoder by means of signal interception and retransmission of the intercepted signal.
Transmitter-Lock
Since the MARCSTAR I E/D devices have a pin-selectable encoder/decoder mode, a safeguard
(Transmitter-Lock) has been designed into the devices. Transmitter-Lock prevents unauthorized parties from
defeating the MARCSTAR security by using a MARCSTAR I E/D device to intercept a transmitted security code
and then transmit the next expected security code to the decoder. The received security code would then be
recognized as coming from the original encoder and, therefore, valid causing the decoder function outputs to
be activated.
The safeguard works by setting an internal flag, stored in EEPROM, whenever the device, in the decoder mode,
learns a code from an encoder. This flag then causes a new 40-bit security code to be generated and stored
in the EEPROM if the device is later placed in the encoder mode and a transmission is ever attempted. So, once
a decoder learn cycle has occurred in a particular MARCSTAR I E/D device, the learned security code will be
overwritten by a new 40-bit security code before output in the encoder mode is permitted. This feature allows
the MARCSTAR I E/D devices to be used as either an encoder or a decoder without sacrificing the security
provided by separate dedicated encoder and decoder devices.
device/system security
Statistically, the probability that a random code would activate the MARCSTAR I E/D devices operating in the
decoder mode is calculated using the formula shown in equation 1.
Probability
valid
+ possible
valid = the number of security codes that activate the device
possible = the total number of possible security codes
where
(1)
A MARCSTAR I E/D device operating in the decoder mode responds to a total of 28 (256) security codes
(including the 256-code look-ahead feature) for each of the four encoders it can learn (256 × 4 valid security
codes).
The total number of possible 40-bit security codes is 240 (1.0995 trillion).
Inserting this into the formula gives equation 2.
Probability
+ 28240 4 +
1
2 30
+
1
1.074
(2)
10 9
Therefore, the security of the entire system is one in 1.074 billion — there is one chance in 1.074 billion that
a random security code would be recognized as valid by a MARCSTAR I E/D device operating in the decoder
mode.
10
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
encoder mode
The MARCSTAR I E/D encoder mode operational flow chart is shown in Figure 3.
Start
N
Sleep Mode
Switch Active
Y
N
Switch Active
Y
Sample Inputs, S1 Data
Read Security Code
Encrypt Security Code
Turn TX LED On
Output Sync Pulses
Output Security Code
Sample Inputs, S2 Data
Output S1 Data
Output S2 Data
Output Dummy Pulse
Wait 150 Bit Times
Turn TX LED Off
N
360 Frames
Y
Y
Switch Active
N
Increment Security Code
and Store in EEPROM
Figure 3. Encoder Mode Operational Flow
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
11
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
encoder mode (continued)
TRC1300 and TRC1315 MARCSTAR I E/D devices are configured as an encoder by holding the CONF terminal
high or by not connecting CONF and allowing the internal pullup to hold it high (a connection to CONF is not
required to select the encoder mode).
In the encoder mode, the device sends a maximum of 360 frames of data out through the DIN/DOUT terminal
when one or any combination of VRC/TX1 – VRC/TX4 terminals is pulled low — when buttons on a remote
transmitter are pressed, for example. The following list and Figure 4 detail the response to various button-press
inputs.
D
D
D
D
D
When a button is pressed, a maximum of 360 frames of data are sent.
Multiple button presses can occur during the output of the 360 frames.
If all buttons are released before all 360 frames are sent, output of data ceases at that point and the timeout
counter resets.
If any buttons are still pressed after all 360 frames have been sent, no additional data is sent and the timeout
counter is not reset.
The timeout counter resets only when all buttons are released, allowing the device to enter a low-power
standby mode while it waits to detect a button press.
Encoder
VRC/TX1-4
Less than
1 Frame
> 360 Frames
n Frames
Encoder
DOUT
1 Frame
343 DCLKs
n Frames
360 Frame Max
Encoder
LED
Figure 4. Encoder Timing
12
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
encoder mode (continued)
Two or more buttons can be pressed at the same time to activate additional functions. Since it is not possible
to press them at exactly the same time, a form of debouncing ensures that only a single function code is received
as valid. Function data is sent in two 12-bit packets. The first function-data packet is derived from the first sample
of the buttons (S1) at the beginning of the frame, and the second function-data packet is derived from the second
sample of the buttons (S2) immediately after the 40-bit security code (see Figure 5). This gives an effective 168
data-clock debounce time because the MARCSTAR I E/D, configured as a decoder, activates function outputs
only when the two function data packets in the frame are identical. When valid function data has been received
in the first packet but the second packet in a frame contains different function data (caused by a second button
being down at sample 2 time), both data packets are discarded and the decoder function outputs remain in their
previous state.
VRC/TX1 –
VRC/TX 4
(active low)
360 Frames
DIN/DOUT
One Complete Frame (343 Bits)
Blank-Time (150 Bits)
Frame Data (193 Bits)
48 Bits
Precode
(Sync)
150 Zero Bits
40 Symbols (120 bits)
Security Code
25 Bits
S1 – Button
Sample 1
Function Data (24 Bits)
4 Symbols
4 Symbols
(12 Bits)
(12 Bits)
S2 – Button Sample 2
Data Packet 1
Data Packet 2
Dummy Pulse (1 Bit)
Figure 5. Transmitted Data Format
If the user is holding buttons B1 and B2 on the transmitter down, both the first button sample (S1) and the second
button sample (S2) should find both buttons down as the next frame is prepared and sent. So, the next frame
that is transmitted should contain the same function data in both the first and the second function data packets,
and the decoder activates function outputs 1 and 2. So as an example, if transmitter button B1 activates the door
locks, button B2 activates the alarm, and both button B1 and button B2 pressed at the same time activates the
trunk lock, the MARCSTAR sampling/debouncing function prevents the door locks and alarm from being
activated when the user intent is to activate only the trunk lock.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
13
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
encoder timing
The rate of the transmitted data is variable from 500 Hz to 5 KHz (adjustable using an external resistor and
optional capacitor) so that the time to send the data in one frame (193 bits) varies from 386 ms to 38.6 ms. When
one or any combination of VRC/TX1 – VRC/TX4 terminals is pulled low, the device outputs up to 360 frames
of data and then stops. This is to prevent indefinite code transmission (and battery depletion) when a transmit
button is pressed continuously, and increases the opportunity for the decoder to detect the transmitted code.
The decoder activates a function output on the first valid received code. The data portions of the transmitted
frames are separated by one dummy pulse and 150 data clock cycles. This gives a lower effective frame duty
cycle, so that the average power output of an interfaced RF oscillator is reduced, and higher peak power can
be used for increased range.
The range of frame duty cycle is dependent on the security and function codes, and can vary as calculated:
D
D
D
D
D
D
D
D
D
Frame duty cycle = total frame high time / total frame time.
Total frame time = 48 + 120 + 24 + 1 + 150 = 343 data clock cycles.
The precode (48 bits) always has a duty cycle of 50%.
The security code (120 bits) duty cycle can vary from 66% (all ones) to 33% (all zeros).
The function data (24 bits) duty cycle can vary from 58% (one function enabled) to 33% (all functions
enabled).
The dummy pulse (1 bit) always has a duty cycle of 100%.
The blank time between frames (150 bits) always has a duty cycle of 0%.
Highest possible duty cycle (48 (0.5) + 120 (0.66) + 24 (0.58) + 1 (1) + 150 (0)) / 343 = 34%.
Lowest possible duty cycle (48 (0.5) + 120 (0.33) + 24 (0.33) +1 (1) + 150 (0)) / 343 = 21%.
Transmitted code format duty cycle is an important consideration when modulating an RF carrier because
regulations in many countries concerning maximum RF power output are specified as average power. In that
respect, higher peak RF power levels can be used, giving increased range, with lower duty-cycle code formats,
such as that found in MARCSTAR systems. In the case of the U.S. FCC (Federal Communications Commission)
regulations, the average radiated field strength is measured, and the 100 ms sliding window of the highest
powered portion of the code frame from the RF transmitter, or the first repeating frame of data, whichever is
shorter, is sampled for average power.
The MARCSTAR I E/D device, configured as an encoder, has a 360 frame transmission timeout. When any
combination of VRC/TX1 – VRC/TX4 terminals are continuously held low, with a 500-Hz data clock rate, the
total transmission time before timeout is 360 × (2 × 10-3 seconds × 343) = 4.1 minutes. Likewise, for a 5-KHz
data clock rate, the total transmission time before timeout is 360 × (2 × 10-4 seconds × 343) = 25 seconds. At
a 1-KHz clock rate, the total transmission time before timeout is 360 × (1 × 10-3 seconds × 343) = 123 seconds.
14
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
transmitted code bit sequence, symbol format, and function code
The effective bit-length of a complete MARCSTAR I E/D encoder output code sequence is 193 bits, as shown
in Figure 5. The output bits, which include the precode, security code, function data, and dummy pulse, change
only on the rising edges of an internal data clock (DCLK). The 150 bit-time blank interval completes the data
frame, which then has a 343 bit-time duration.
When a MARCSTAR I E/D encoder function input is activated, the stored 40 bits of security code are first
translated into 40 symbols, with each symbol consisting of three bits, before being output by the device. A
security code zero bit is translated into symbol 0, which is represented by the bit sequence 100. A security code
one bit is translated into symbol 1, which is represented by the bit sequence 110. The function data is also
translated into symbols of this format before being output.
The result of using these particular bit sequences to represent a 1 or 0 symbol is an increase in decoder function
robustness. It also simplifies and improves the accuracy of the comparator adaptive threshold circuitry (see
Amplifier/Comparator section).
Function differentiation is provided by four function bits that are translated into symbols by the encoder and
sent twice in each data frame to identify the functions that are to be activated at the decoder. Function data is
transmitted twice per frame to reduce the probability that accurate security code data and corrupt function data
could cause unwanted activation of a function.
After the 40 symbols are decoded into 40 security code bits and found to match a 40-bit security code stored
in the decoder EEPROM memory, the next four symbols are decoded into the first set of four function code bits,
and the final four symbols are decoded into the second set of four function code bits. The two sets of 4-bit
function code are then compared, and if found to match, the function code is used to enable the appropriate
function output as shown in Table 1.
Table 1. Function Code
FUNCTION
BIT 1
BIT 2
BIT 3
BIT 4
1
0
1
1
1
2
1
0
1
1
3
1
1
0
1
4
1
1
1
0
More than one encoder function input can be activated at the same time. An external 4-bit binary decoder can
be used to control up to 15 devices, one at a time, based on the four MARCSTAR I E/D decoder function outputs.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
15
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
decoder mode
The MARCSTAR I E/D decoder mode operational flow is shown in Figure 6.
Start
Measure Sync Pulse
Identify Valid Sync
N
Sync Complete
Y
Wait for Dummy Pulse
N
8 Valid Sync
Pulses
Y
Receive Security Code
Wait for Dummy Pulse
N
Valid Code
Y
Receive S1 Data
Receive S2 Data
Assert Outputs
Y
Data Valid
N
Update Security Code
Reset Frame Counter
Figure 6. Decoder Mode Operational Flow
16
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
decoder mode (continued)
The TRC1300 and TRC1315 MARCSTAR I E/D devices are configured as a decoder by holding the CONF
terminal low before the device is powered up (the device reads the CONF terminal during POR, power-on reset).
In the decoder mode, the device receives serial data from input terminal DIN/DOUT. The input data signal is
first passed through the internal amplifier/comparator for signal conditioning before being decoded and
compared with the four 40-bit security codes stored in EEPROM memory. When a match is found with one or
more received data frames, the appropriate function output terminals, VRC/TX1 – VRC/TX4, are enabled
(active-low). The decoder activates a function output only when two identical function data packets are received
in the same frame. The function output remains active for a minimum period of 768 data clock cycles, which
can range from 154 ms to 1.54 seconds, depending on the clock frequency used. With a 1-KHz data clock rate,
for example, a function output is asserted for a minimum of 768 ms. The decoder keeps the appropriate function
output terminals (VRC/TX1 – VRC/TX4) active as long as it receives valid code, and through the blank time
between each frame, which is 150 clock cycles. The function outputs go inactive when invalid function data code
is received.
Configured as a decoder, the MARCSTAR I E/D samples the incoming serial data at 10 times the expected
transmitted data rate. As each symbol is sampled, an integrator determines if it represents a 1 or 0 by the total
number of high and low samples. A high symbol (110) has a high level for approximately two-thirds of the symbol
period, while a low symbol (100) is high for only one-third of the symbol period. Therefore, if five or more out
of eight of the samples are high, the symbol is decoded as a 1, and if three or fewer of the samples are high,
the symbol is decoded as a 0. The symbol format also improves synchronization of the decoder with the
incoming serial data. A transition from low to high always signifies the beginning of a symbol.
The method of synchronization employed by MARCSTAR I E/D uses a precode sync pattern that precedes the
security and function data portions of each frame sent by the encoder. The precode consists of 24 pulses with
a 50% duty cycle, each being high or low for one period of the data clock. This equates to a total of 48 bit times.
amplifier/comparator
A representation of the amplifier/comparator section of the MARCSTAR I E/D devices is shown in Figure 7. This
circuit is used to amplify and wave-shape low-level input signals to logic levels for input to the shift registers.
The internal R1 and C1 components combination form a reference-setting (autobias) network, and the time
constant of this network is about three symbols, or 12 bits of code. The internal components R2 and C2 form
a low-pass network with a time constant equal to approximately one-tenth of one DCLK period so that
high-frequency transients are attenuated before reaching the comparator.
IN
+
DIN/DOUT _
Unity-Gain
Buffer
R2
+
_
Amplifier/
Comparator
R1
C1
To Shift
Registers
C2
Figure 7. Amplifier/Comparator Equivalent Schematic
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
17
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
amplifier/comparator (continued)
The amplifier/comparator is implemented with advanced switched-capacitor technology. This is done for two
primary reasons. First, since the TRC1300 and TRC1315 devices are variable frequency, the values of R1, C1,
R2, and C2 must change depending on the received data rate. Since they are a switched-capacitor design, the
filter characteristics scale depending on the oscillator in the decoder device, which must match the encoder
oscillator frequency. With this scheme, the amplifier/comparator section functions at all received code data
rates. The second reason for using switched-capacitor filters is the increased accuracy and precise filter
response that they provide.
programming mode
The MARCSTAR I E/D devices have been designed so that no programming station is required to load the
security codes into the EEPROM memory. When the device is configured as an encoder, it generates a 40-bit
security code and stores it in EEPROM memory. When configured as a decoder, the device learns the security
code from up to four different encoders.
EEPROM stored-code format
The EEPROM memory contains four banks that are used for 40 bits of security code for each of the four channels
and an additional 32 bits (eight bits per channel) for error detection. The total EEPROM memory is 192 bits.
When configured as a decoder, these EEPROM banks store up to four learned 40-bit security codes; when
configured as an encoder, only the first bank of 40 bits is used for the security code.
programming — encoder
When a MARCSTAR I E/D device is configured as an encoder and placed in the programming mode, it
generates a 40-bit security code and stores it in the first 40-bit EEPROM memory bank. The remaining three
40-bit memory banks are unused. An LED connected to the LED terminal is required to verify a proper write
sequence to EEPROM. The LED anode should be connected to the positive supply and the cathode should be
connected to the LED terminal of the MARCSTAR I E/D through a current-limiting resistor.
The procedure for programming a MARCSTAR I E/D device configured as an encoder is described in the
following steps:
1. Connect the proper RC combination to the OSCR and OSCC terminals to set the frequency of the
internal oscillator.
2. Connect GND and then apply VCC.
3. Apply a logic high to PROG (the PROG terminal is internally pulled down and debounced). The device
assumes the program mode. The LED lights, the device generates a new 40-bit security code internally,
it loads the first memory bank with that code, and then extinguishes the LED.
4. The MARCSTAR I E/D encoder is now programmed with a new 40-bit security code. Each time step 3 is
repeated, a new 40-bit security code is generated and then loaded into the first EEPROM memory
location, overwriting the previous security code.
18
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
programming — smart decoder (learn mode)
The MARCSTAR I E/D configured as a smart decoder has the capability of learning up to four 40-bit security
codes from four separate encoders. If the decoder attempts to learn a fifth encoder security code, the decoder
logic overwrites the first stored security code with the fifth encoder security code. This FIFO (first in, first out)
operation always causes the oldest code to be overwritten. When an encoder is lost and a new encoder is
learned by the decoder, all four of the encoders now being used with the decoder should be relearned to ensure
that the decoder contains all the current encoder security codes and no longer stores the security code from
the lost encoder. When there are fewer than four encoders being used with a particular decoder, any of them
can be learned more than once (for a total of four) to fill the remaining decoder security code storage locations
and ensure that the code for the lost encoder has been overwritten.
Each 40-bit security code is loaded into a EEPROM in a single write sequence. An LED connected to the LED
terminal is required to verify a proper write sequence to EEPROM memory. The LED anode should be
connected to positive supply and the cathode to the LED terminal of the MARCSTAR I E/D through a
current-limiting resistor (the LED terminal is active low).
The procedure to write each 40-bit security code into the decoder EEPROM is as follows:
1. Connect the proper RC combination to the OSCR and OSCC terminals to set the frequency of the
internal oscillator.
2. Connect the CONF terminal to GND. CONF, which is internally pulled up, must be tied to GND before the
device is powered up so that when the internal microcontroller reads the CONF terminal during POR
(power on reset), CONF will already be at GND.
3. Connect the device to system GND and then VCC.
4. Apply a logic high to PROG (the PROG terminal is internally pulled down and debounced). The device
assumes the program mode and the LED lights. The PROG terminal must be held at logic high for the
duration of the programming sequence.
5. Apply the MARCSTAR I E/D encoder security code data to be programmed to DIN/DOUT. The first
received frame of data is decoded into a 40-bit security code sequence and loaded into the first memory
bank of the EEPROM. The LED turns off after the device has decoded and stored the received data. The
logic high should now be removed from the PROG terminal. The LED stays on if an attempt is made to
exit the programming mode without learning a code.
6. To learn up to four encoder security codes, repeat steps 4 and 5. Each time the device is programmed,
the next available memory bank is used, up to four banks.
NOTE: In order to prevent unauthorized programming of the decoder, it is suggested that access to the learn mode be limited to the
manufacturer or dealer. In cases where end-user programming is required, a key-switch can limit programming to authorized
individuals only.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
19
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
oscillator
An internal variable-rate clock runs at the SCLK (sample clock) frequency, and is adjustable from 5 kHz to
50 kHz. DCLK (data clock) is derived from SCLK so that both clocks are synchronous. DCLK runs at one-tenth
the speed of SCLK and clocks the transmitted data at a rate variable from 500 bps to 5 kbps. SCLK is used to
sample the received data at 10 times the received data rate. The high sampling rate in the decoder combined
with the symbol code format and the internal signal-conditioning amplifier circuitry provides accurate correlation
of the received signal. The SCLK frequency is set by an external RC at terminals OSCR and OSCC.
The encoder and decoder should be set to the same clock rates; however, the device allows a wide frequency
tolerance to increase the robustness of the communications link. The encoder can vary from one-half to two
times the decoder clock speed and synchronization still results. This allows for internal oscillator tolerance and
frequency change due to external component tolerances and temperature changes. For example, if a serial data
speed of 1.5 kbps (DCLK) is desired, then both the encoder and the decoder oscillators (SCLK) must be set
to be 10 times the data rate frequency, or 15 kHz. Both the encoder and decoder can vary ± 33% in frequency,
or from 10 kHz to 20 kHz, and the devices still synchronize successfully. For the worst case example, the
encoder SCLK would be running at 10 kHz and the decoder SCLK at 20 kHz, or twice the encoder frequency.
The absolute maximum and minimum clock frequency of 5 kHz to 50 kHz must never be violated. Because the
device introduces up to ± 7% frequency variation, the external RC components can have as much as ± 26%
tolerance, for a total of ± 33% frequency variation.
The encoder and decoder internal SCLK clock rate is set by connecting a resistor between the OSCR and OSCC
terminals and an optional capacitor between the OSCC terminal and GND on each device. Equation 3 defines
the internal sample clock (SCLK) as a function of the external resistor and capacitor.
f
osc
+
1.386
ǒ
R
Ǔǒ
1
3
10
)2
ext
C
) 20
ext
10
Ǔ
(3)
–12
The 2 × 10 3 value (2 kΩ) shown in equation 3 is the internal series resistance with OSCR. The
20 × 10 –12 value (20 pF) is the internal capacitance value of the OSCC bond pad (a parasitic shunt capacitance
to GND). Figure 8 shows typical Rext values vs. SCLK frequency.
50
Cext = 0.001 µF
f – Frequency – kHz
40
30
20
10
0
12
16
20
24
28
32
36
40
44
48
52
56
60
Rext – External Resistance – kΩ
Figure 8. External Resistance vs. Sample Clock Frequency (SCLK)
20
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
64
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
PRINCIPLES OF OPERATION
test mode
TRC1300 and TRC1315 MARCSTAR I E/D devices are equipped with a self-test function that checks the RAM,
ROM, and EEPROM memory areas:
D
D
D
The RAM is tested by writing checkerboard bit patterns into the RAM and then reading them back. The test
is passed if the correct data is read from the RAM.
The ROM is tested by calculating a new checksum for each location containing data and then comparing
it to a predetermined value. The test is passed if the two values match.
The EEPROM is tested by calculating a new checksum for each of the four 40-bit locations and comparing
them with checksum values stored in EEPROM. The test is passed if the two values match.
When TEST is momentarily held at VCC, the device enters the self-test mode. While in this mode, the device
runs through the tests and then indicates results with a flashing LED. The result codes are shown in Table 2.
Table 2. LED Flashing Self-Test Error Codes
LED FLASHES
CONDITION
0
No tests passed
1
Passed EEPROM test only
2
Passed ROM test only
3
Passed ROM and EEPROM tests
4
Passed RAM test only
5
Passed RAM and EEPROM tests
6
Passed RAM and ROM tests
7
Passed all tests
The switch that initiates the test mode should be momentary — the device continues to run through the tests
as long as TEST is held at VCC.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
21
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
APPLICATION INFORMATION
4-channel, direct-wired
Figure 9 shows an example of MARCSTAR I E/D devices in a single-wire direct connection. This configuration
is typically used in cable-box decoders, remote lighting, and wired home-security-system applications. U1 is
a TRC1300 configured as an encoder by not connecting the CONF terminal (which is internally pulled up, so
no connection is required). U2, a TRC1315, is configured as a decoder by tying CONF low (CONF must be low
before VCC is applied). PROG is held low by an internal pulldown to disable the program mode. Closing the
Learn switch places U2 in the program mode so that the security code from an encoder can be learned. Both
the encoder and decoder are set to a 2-kHz data clock (DCLK) frequency (20 kHz sample clock, SCLK) using
an external RC at OSCC and OSCR. An LED is connected through a resistor to the LED terminal of the encoder
and indicates transmission of code. When momentary switches S1 – S4 are pressed, the corresponding outputs
on the U2 decoder go low and LEDs D1 – D4 light.
3V
1 µF
0.1 µF
Channel 4
1 kΩ 1
4
12
13
7
1 kΩ 1
VRC/TX1
GND
8
VRC/TX2
9
VCC
10
VRC/TX3
11
VRC/TX4
OSCR
6
2
3
4
TEST
U2 TRC1315 (decoder)
LED
GND
VCC
TEST
LED
PROG
3
RX
5
OSCC
VRC/TX1
More Than One Switch
Can Be Pressed At a
Time
U1 TRC1300 (encoder)
2
14
CONF
8
Channel 1
DIN/DOUT VCC/CAP
9
VRC/TX2
10
VRC/TX3
11
R1– R4
220 kΩ
33 kΩ
Channel 2
VRC/TX4
6
OSCR
OSCC
5
CONF
TX
DIN/DOUT VCC/CAP
14
0.001 µF
Channel 3
33 kΩ
PROG
0.001 µF
D1– D4
0.1 µF
12
13
7
0.1 µF
Learn
NOTE A: Terminal numbers are for the D package.
Figure 9. A 4-Channel, Single-Wire Connection
22
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
12 V
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
APPLICATION INFORMATION
4-channel, infrared or RF connection
Figure 10 shows an example of MARCSTAR I E/D devices in an infrared or RF connection, typically used in
automobile RKE or security systems. U1 is a TRC1300 configured as an encoder by not connecting the CONF
terminal (which is internally pulled up, so no connection is required). U2, a TRC1315, is configured as a decoder
by tying CONF low (CONF must be low before VCC is applied). PROG is held low by an internal pulldown to
disable the program mode. Closing the Learn switch places U2 in the program mode so that the security code
from an encoder can be learned. Both the encoder and decoder are set to a 2-kHz data clock (DCLK) frequency
(20 kHz sample clock, SCLK) using an external RC at OSCC and OSCR. An LED is connected through a resistor
to the LED terminal of the encoder and indicates transmission of code. Momentary switches S1 – S4 are
internally debounced and pulled up at device inputs VRC/TX1– VRC/TX4. When S1– S4 is pressed, the
corresponding outputs on the U2 decoder go low and LEDs D1 – D4 light.
3V
D1– D4
0.1 µF
S4 — Channel 4
S3 — Channel 3
S2 — Channel 2
S1 — Channel 1
1 kΩ
1
4
12
13
7
1 kΩ 1
TX
8
VRC/TX1
9
VRC/TX2
10
VRC/TX3
11
VRC/TX4
6
OSCR
5
2
3
4
12
13
GND
VCC
TEST
U2 TRC1315 (decoder)
LED
GND
RX
VCC
TEST
LED
PROG
3
14
More Than One Switch
Can Be Pressed At a Time
U1 TRC1300 (encoder)
2
33 kΩ
PROG
8
R1– R4
1 kΩ
0.001 µF
OSCC
9
VRC/TX1
10
VRC/TX3
11
VRC/TX4
6
OSCR
OSCC
5
CONF
TX
DIN/DOUT VCC/CAP
14
VRC/TX2
33 kΩ
1 µF
CONF
0.001 µF
DIN/DOUT VCC/CAP
0.1 µF
7
0.1 µF
RX
Learn
12 V
NOTE A: Terminal numbers are for the D package.
Figure 10. A 4-Channel, RF/Infrared Connection
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
23
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
APPLICATION INFORMATION
16-channel, infrared or RF connection
Figure 11 shows an example of MARCSTAR I E/D devices in a 16-channel infrared or RF connection, typically
used in consumer electronics (TV, VCR, etc.) or remote-control toy applications. U1 is a TRC1300 configured
as an encoder by not connecting the CONF terminal (which is internally pulled up, so no connection is required).
U2, a TRC1315, is configured as a decoder by tying CONF low (CONF must be low before VCC is applied).
PROG is held low by an internal pulldown to disable the program mode. Closing the Learn switch places U2
in the program mode so that the security code from an encoder can be learned. Both the encoder and decoder
are set to a 2-kHz data clock (DCLK) frequency (20 kHz sample clock, SCLK) using an external RC at OSCC
and OSCR. An LED is connected to the LED terminal of the encoder and indicates transmission of code. The
outputs of a 4-bit binary encoder are connected to inputs VRC/TX1 – VRC/TX4 of the MARCSTAR I E/D encoder.
When one of the 16 momentary switches (S1 – S16) is pressed, the binary equivalent is encoded by U3 and
applied to the MARCSTAR I E/D encoder (U1) inputs. The binary equivalent is transmitted to the MARCSTAR
I E/D decoder (U2) where the corresponding outputs go low. The inputs of a 4-bit binary decoder are connected
to the VRC/TX1 – VRC/TX4 outputs of the MARCSTAR I E/D decoder. When these terminals output the received
binary function data, they are then decoded by U4, and the appropriate U4 output is activated. The outputs can
be used to control one of 15 devices at a time, or for a 15 position semiproportional control.
S1
U3
One Switch at
a Time May Be
Pressed
3V
U4 4-Bit Binary Decoder
QA
QD
QC
QB
4-Bit
Binary
Encoder
0.1 µF
1 µF
0.1 µF
1 kΩ
1
R1– R4
22 kΩ
0.001 µF
QD
33 kΩ
QB
QA
0.001 µF
2
3
4
12
13
7
1 kΩ
TX
RX
1
2
3
12
13
VRC/TX1
GND
7
0.1 µF
Figure 11. A 16-Channel, RF or Infrared Connection
• DALLAS, TEXAS 75265
VCC
TEST
LED
4
Learn
NOTE A: Terminal numbers are for the D package.
POST OFFICE BOX 655303
8
U2 TRC1315 (decoder)
12 V
24
9
VRC/TX2
10
VRC/TX3
11
VRC/TX4
6
OSCR
OSCC
5
PROG
GND
RX
VCC
TEST
LED
PROG
U1 TRC1300 (encoder)
14
CONF
8
33 kΩ
S16
DIN/DOUT V /CAP
CC
9
VRC/TX1
10
VRC/TX3
11
VRC/TX2
QC
VRC/TX4
6
OSCR
OSCC
5
CONF
DIN/DOUT VCC /CAP
14
TX
Output 16
Output 1
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
MECHANICAL DATA
D (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
14 PIN SHOWN
PINS **
0.050 (1,27)
8
14
16
A MAX
0.197
(5,00)
0.344
(8,75)
0.394
(10,00)
A MIN
0.189
(4,80)
0.337
(8,55)
0.386
(9,80)
DIM
0.020 (0,51)
0.014 (0,35)
14
0.010 (0,25) M
8
0.244 (6,20)
0.228 (5,80)
0.008 (0,20) NOM
0.157 (4,00)
0.150 (3,81)
1
Gage Plane
7
A
0.010 (0,25)
0°– 8°
0.044 (1,12)
0.016 (0,40)
Seating Plane
0.069 (1,75) MAX
0.010 (0,25)
0.004 (0,10)
0.004 (0,10)
4040047 / B 03/95
NOTES: A.
B.
C.
D.
E.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion, not to exceed 0.006 (0,15).
Four center pins are connected to die mount pad.
Falls within JEDEC MS-012
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
25
TRC1300, TRC1315
MARCSTAR I E/D
REMOTE CONTROL ENCODER/DECODERS
SLWS011D – AUGUST 1996 – REVISED JANUARY 1997
MECHANICAL DATA
N (R-PDIP-T**)
PLASTIC DUAL-IN-LINE PACKAGE
16 PIN SHOWN
PINS **
14
16
18
20
A MAX
0.775
(19,69)
0.775
(19,69)
0.920
(23.37)
0.975
(24,77)
A MIN
0.745
(18,92)
0.745
(18,92)
0.850
(21.59)
0.940
(23,88)
DIM
A
16
9
0.260 (6,60)
0.240 (6,10)
1
8
0.070 (1,78) MAX
0.035 (0,89) MAX
0.310 (7,87)
0.290 (7,37)
0.020 (0,51) MIN
0.200 (5,08) MAX
Seating Plane
0.125 (3,18) MIN
0.100 (2,54)
0.021 (0,53)
0.015 (0,38)
0.010 (0,25) M
0°– 15°
0.010 (0,25) NOM
14/18 PIN ONLY
4040049/C 08/95
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. Falls within JEDEC MS-001 (20 pin package is shorter then MS-001.)
26
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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