SAE J2716 SENT Protocol Decoder
Decode SAE J2716 SENT fast-channel frames from nibble values or measured pulse tick counts. Inspect synchronization timing, status nibble, data nibbles, assembled sensor value, CRC nibble, pause pulse and total frame timing.
N using
12 + N ticks, so a 12-tick pulse represents 0 and a 27-tick
pulse represents 15.
| # | Field | Nibble | Hex | Pulse Ticks | Pulse Time |
|---|
—
What Is the SAE J2716 SENT Protocol?
SENT stands for Single Edge Nibble Transmission. It is a unidirectional digital communication protocol commonly used by automotive sensors to send measurement information to an electronic control unit.
Unlike protocols that encode information using conventional bytes and a separate clock line, SENT communicates values through the time between successive falling edges. Each status, data or CRC nibble is represented by a pulse period measured in protocol ticks.
SENT Pulse-to-Nibble Formula
Pulse Period =
12 + Nibble Value
Therefore:
Nibble Value =
Pulse Ticks - 12
The smallest ordinary nibble pulse is 12 ticks and represents hexadecimal
0. The largest is 27 ticks and represents hexadecimal
F.
SENT Pulse Tick Table
| Nibble | Pulse Length |
|---|---|
| 0x0 | 12 ticks |
| 0x1 | 13 ticks |
| 0x2 | 14 ticks |
| 0x3 | 15 ticks |
| 0x4 | 16 ticks |
| 0x5 | 17 ticks |
| 0x6 | 18 ticks |
| 0x7 | 19 ticks |
| 0x8 | 20 ticks |
| 0x9 | 21 ticks |
| 0xA | 22 ticks |
| 0xB | 23 ticks |
| 0xC | 24 ticks |
| 0xD | 25 ticks |
| 0xE | 26 ticks |
| 0xF | 27 ticks |
SENT Synchronization / Calibration Pulse
A fast-channel SENT message begins with a synchronization or calibration pulse. Its nominal period is 56 ticks and allows the receiver to determine the transmitter’s actual tick duration before decoding the following nibble pulses.
Nominal Sync Pulse:
56 ticks
Example tick:
3 µs
Sync Pulse Time:
56 × 3 µs
= 168 µsSENT Fast-Channel Frame Structure
Synchronization / Calibration Pulse
Status & Communication Nibble
Data Nibble 1
Data Nibble 2
...
Data Nibble N
CRC Nibble
Optional Pause PulseThe number and interpretation of data nibbles depends on the sensor and its defined SENT message format. This decoder therefore assembles the nibbles numerically without inventing physical units such as pressure, temperature or position.
Status and Communication Nibble
The first nibble following synchronization is the Status and Communication Nibble. Its four bits may carry sensor status and serial-message-related information depending on the SENT implementation.
Because the precise semantic meaning is sensor-specific, the calculator shows the nibble in hexadecimal and binary rather than assigning unsupported fault or operating-state names.
SENT Fast-Channel Data Value
When several data nibbles form one numeric fast-channel value, they can be concatenated in transmission order. For example, six nibbles contain 24 bits of raw information.
Data Nibbles:
1 2 3 4 5 6
Combined Hex:
0x123456
Combined Decimal:
1193046Whether those 24 bits represent one value, two 12-bit sensor values or another application-specific layout is defined by the sensor documentation.
SENT CRC Nibble
The fast-channel frame ends with a four-bit CRC nibble used to detect errors in the status and data nibbles. SAE J2716 has defined CRC behavior that has changed across protocol revisions and implementation profiles, so the calculator exposes its selected CRC model instead of assuming every sensor uses an undocumented variant.
This page uses the common SENT fast-channel CRC-4 implementation based on
polynomial x⁴ + x³ + x² + 1, represented as
0x0D for the four-bit register update, with initial seed
0x05. Sensor documentation should remain the final authority when
a device uses revision-specific CRC details.
SENT Pause Pulse
A pause pulse may follow the CRC nibble. It can be used to extend the total message duration so that consecutive frames maintain a desired repetition period.
The pause pulse does not represent another data nibble. If its length is known, this calculator can include it when estimating the total frame timing.
Example SENT Timing Calculation
Tick Time:
3 µs
Nibble:
0x5
Pulse Ticks:
12 + 5
= 17 ticks
Pulse Period:
17 × 3 µs
= 51 µsSENT vs PWM
SENT should not be interpreted as ordinary PWM duty-cycle encoding. The information is determined primarily by the measured period between defined signal edges, expressed in units of the calibrated SENT tick.
That makes edge timing and correct synchronization-pulse measurement important when decoding oscilloscope, logic-analyzer or timer-capture data.
SAE J2716 SENT Protocol Decoder FAQs
What does SENT stand for?
What standard defines SENT?
How is a SENT nibble encoded?
How many ticks represent SENT nibble 0?
How many ticks represent hexadecimal F?
How long is the SENT synchronization pulse?
What is the status nibble?
How many data nibbles does SENT use?
What is the SENT CRC nibble?
Can this decoder determine pressure or temperature automatically?
What is a SENT pause pulse?
Decode SENT Nibbles and Pulse Timing
Convert SAE J2716 pulse periods to nibble values, inspect status and data fields, assemble fast-channel values, check the CRC nibble and estimate SENT frame timing.