Pinout & Connectors

Complete pin assignments and connector reference for the H7-Digital flight controller, including all connectors, motor outputs, UARTs, and special functions.

Quick Reference
1. Board Specifications
2. Pinout Diagrams
UART Mapping
1. Complete UART Reference
2. ArduPilot Protocol Numbers
Power System
1. Battery Input
2. Regulated Power Outputs
Connectors
1. ESC Connector (8-pin JST-SH)
2. Motors 5-8 Connector (6-pin JST-SH)
3. RC Input Connector (4-pin JST-SH)
4. Servos Connector (4-pin JST-SH)
5. GPS/Compass Connector (6-pin JST-SH)
6. VTX (Video Transmitter) Connector (6-pin JST-SH)
7. Companion Computer Connector (4-pin JST-SH)
8. USB-C Connector
Motor Outputs (M1-M8)
1. Motor Pin Assignments
2. Motor Numbering Convention
3. Bidirectional DShot Support
Servo Outputs (S1-S2)
1. Servo Pin Assignments
Understanding ESC Telemetry Methods
1. Method 1: UART-Based ESC Telemetry (Traditional)
2. Method 2: Bidirectional DShot (Modern)
3. Method 3: Extended DShot Telemetry (EDT) - Best of Both Worlds
4. Comparison Table
5. Which Method Should I Use?
6. Performance Comparison
7. External Resources
I2C Ports
1. I2C Pin Assignments
SPI Ports
1. SPI1 (Internal IMU)
ADC Inputs (Analog Sensing)
GPIO and Special Functions
1. Status LEDs
2. VTX Power Control
3. BOOT Button
Board Orientation and Mounting
1. Board Orientation
2. Mounting Pattern
Wiring Best Practices
1. Cable Routing
Solder Pads (Alternate Connections)
Troubleshooting Connection Issues
Connector Standard
1. JST-SH Series
Cable Compatibility Matrix
1. Pre-Made Cable Sources
Related Documentation
External Resources
Support

Quick Reference

Board Specifications

Specification	Value
Board Size	41mm × 41mm
Mounting Holes	M3 (4 holes)
Mounting Pattern	30.5mm standard spacing
Connector Standard	JST-SH - BetaFlight Connector Standard
Signal Voltage	3.3V logic

Pinout Diagrams

H7-Digital Complete Pinout Diagram - Labeled wiring diagram showing all connector locations, pin assignments, and component layout for ESC, GPS, VTX, RC, and all other connections

Click image to view full size

Labeled wiring diagram showing all connector locations and pin assignments

The arrow on the board indicates the forward direction of the aircraft. Orient your flight controller with the arrow pointing toward the front of your vehicle.

UART Mapping

Complete UART Reference

UART	TX Pin	RX Pin	Default Protocol	DMA (ArduPilot)	DMA (BetaFlight)	Connector/Location	Primary Use
UART2	PA2	PA3	DisplayPort (42)	✓	※	VTX connector	MSP OSD to digital VTX
UART3	-	PD9	ESC Telemetry (16)	✗	※	ESC connector Pin 4	ESC RPM/voltage/current (RX only)
UART4	PD1	PD0	RCIN (23)	✓	※	RC connector	SBUS/CRSF/ELRS receiver
UART5	PB13	PB12	MAVLink2 (2)	✓	※	COMPUTER connector	Raspberry Pi/Jetson
UART7	-	PE7	None (0)	✓	※	VTX connector R7	DJI SBUS input (RX only)
UART8	PE1	PE0	GPS (5)	✓	※	GPS connector	GPS module

DMA Configuration:

ArduPilot: UART3 RX (ESC Telemetry) has DMA explicitly disabled. This is intentional for ESC telemetry, which defaults to a low 10Hz update rate. Without DMA, each received byte triggers a CPU interrupt. At 10Hz with 10-byte packets (100 bytes/sec at 115200 baud), interrupt overhead is negligible. DMA would provide no benefit at such low data rates, and the NODMA configuration frees up DMA channels for higher-bandwidth peripherals.

Betaflight: All UART DMAs are disabled by default to avoid DMA resource conflicts with bidirectional DShot. Betaflight prioritizes bidirectional DShot (400Hz motor telemetry) over UART DMA. (※ = Conditionally available when bidirectional DShot is disabled or on non-conflicting DMA streams)

ArduPilot Protocol Numbers

Common SERIALx_PROTOCOL values:

0 = None (disabled)
2 = MAVLink2 (telemetry/companion)
5 = GPS
16 = ESC Telemetry
23 = RC Input (SBUS/CRSF/etc.)
42 = MSP DisplayPort (OSD)

Power System

Battery Input

Connection	Location	Voltage Range	Notes
VBAT	ESC connector Pin 1	11.1V - 25.2V (3S-6S)	Main power input
GND	ESC connector Pin 2	Ground	Common ground

Regulated Power Outputs

Output	Voltage	Current	Available On	Purpose
5V	5.0V	2.5A peak, 2A continuous	Servos connector	Servo power (VBAT only)
4.5V	4.5V nominal	2.5A peak, 2A continuous	RC Input, GPS connectors	Peripherals (USB or VBAT)
10V	10.0V	2.5A peak, 2A continuous	VTX connector only	Digital HD VTX power

5V and 4.5V Rails Share Same BEC: Both the 5V and 4.5V outputs are powered from the same 5V BEC (2A continuous, 2.5A peak total). The difference:

5V rail: Direct BEC output (5V pads, e.g Servos connector) - only powered when VBAT is connected

4.5V rail: BEC or USB power auto-select (RC Input, GPS connectors) - powered when either USB is connected or VBAT

10V Output is VTX Only: The 10V BEC is designed exclusively for digital HD video transmitters. Do NOT connect standard 5V peripherals to the 10V output. Damage will occur.

USB Power for Bench Testing: The 4.5V rail is powered from either USB or battery (auto-select). You can test the flight controller with GPS, compass, and RC receiver via USB power alone (no battery required).

Connectors

ESC Connector (8-pin JST-SH)

Location: Bottom side, top edge, right
Connector Type: 8-pin JST-SH

Pin	Label	Signal	STM32 Pin	Timer	Voltage	Function
1	BAT	VBAT	-	-	11.1V - 25.2V	Battery positive (3S-6S)
2	G	GND	-	-	Ground	Battery negative / common ground
3	C	Current	PA1	ADC1	3.3V analog	Current sensor input from ESC
4	T	Telemetry	PD9	UART3 RX	3.3V UART	ESC telemetry (RX only)
5	M1	Motor 1	PE9	TIM1_CH1	3.3V PWM	Motor 1 signal
6	M2	Motor 2	PE11	TIM1_CH2	3.3V PWM	Motor 2 signal
7	M3	Motor 3	PE13	TIM1_CH3	3.3V PWM	Motor 3 signal
8	M4	Motor 4	PE14	TIM1_CH4	3.3V PWM	Motor 4 signal

Default Protocols:

Motor signals: DShot600 (recommended) or DShot300
Telemetry: ESC telemetry protocol (RX only on T pin) OR bidirectional DShot (on motor signal wires)

Configuration:

ArduPilot: SERIAL5_PROTOCOL = 16 (ESC Telemetry)
Betaflight: Ports tab → Enable “ESC” on UART3

Included Cable:

1x JST-SH 8-pin to JST-SH 8-pin cable (for 4-in-1 ESCs)

4-in-1 ESC Connection: Always double check that the intended ESC pinout matches the H7-Digital ESC pinout before using the included 8-pin JST-SH ESC connector. Manufacturers often use different/incompatible pinout standards.

ESC Telemetry Options: The H7-Digital supports three telemetry methods: UART-based ESC telemetry (via Pin 4), bidirectional DShot (via motor signal wires, RPM only), or Extended DShot Telemetry/EDT (via motor signal wires, comprehensive data). See Understanding ESC Telemetry Methods below for detailed comparison and configuration.

Wiring Notes:

Wire gauge: 22-24 AWG for ESC-to-FC connection (standard JST-SH pre-wired cables at <30mm length)
Motor signals: Keep as short as possible (≤15cm recommended)
Signal integrity: Route motor signal wires away from high-current VBAT wires

Motors 5-8 Connector (6-pin JST-SH)

Location: Bottom side, top edge, left
Connector Type: 6-pin JST-SH

Pin	Label	Signal	STM32 Pin	Timer	Voltage	Function
1	NC	Not Connected	-	-	-	Reserved (no connection)
2	G	GND	-	-	Ground	Common ground
3	M5	Motor 5	PD12	TIM4_CH1	3.3V PWM	Motor 5 signal
4	M6	Motor 6	PD13	TIM4_CH2	3.3V PWM	Motor 6 signal
5	M7	Motor 7	PD14	TIM4_CH3	3.3V PWM	Motor 7 signal
6	M8	Motor 8	PD15	TIM4_CH4	3.3V PWM	Motor 8 signal

Use Cases:

Octocopter / X8 configurations (8 motors total)
Hexacopter + camera gimbal control
Additional motor outputs for VTOL/tiltrotor

No Power Pin: This connector does not provide power from the second ESC.

RC Input Connector (4-pin JST-SH)

Location: Top side, top edge, right
Connector Type: 4-pin JST-SH

Pin	Label	Signal	STM32 Pin	Voltage	Function
1	4V5	Power	-	4.5V @ 2A	Receiver power (from 5V BEC or USB)
2	G	GND	-	Ground	Common ground
3	R4	RX	PD0	3.3V UART	Receiver signal input (UART4 RX)
4	T4	TX	PD1	3.3V UART	Receiver telemetry output (UART4 TX)

Supported Protocols:

SBUS (FrSky, Futaba)
CRSF (TBS Crossfire)
ELRS (ExpressLRS)
DSM/DSMX (Spektrum)
PPM (legacy)

Configuration:

ArduPilot: SERIAL4_PROTOCOL = 23 (RC Input)
Betaflight: Receiver tab → Serial-based receiver

Bidirectional Protocols: CRSF and ELRS support telemetry back to the transmitter (battery voltage, GPS, RSSI). Connect both RX and TX for full bidirectional communication.

USB Power for Bench Testing: The RC connector is powered from the 4.5V rail (5V BEC or USB). You can test RC binding via USB power alone (no battery required).

Servos Connector (4-pin JST-SH)

Location: Top side, top edge, left
Connector Type: 4-pin JST-SH

Pin	Label	Signal	STM32 Pin	Timer	Voltage	Function
1	5V	Power	-	-	5V @ 2A	Servo power (from 5V BEC)
2	G	GND	-	-	Ground	Common ground
3	S1	Servo 1	PC6	TIM3_CH1	3.3V PWM	Servo 1 signal (PWM output 9)
4	S2	Servo 2	PC7	TIM3_CH2	3.3V PWM	Servo 2 signal (PWM output 10)

Applications:

Camera gimbal (pan/tilt)
Landing gear retraction
Parachute deployment
Cargo drop mechanisms
Control surface mixing (for fixed-wing/VTOL)

PWM Frequency: Configurable 50Hz-490Hz (50Hz standard for analog servos)

Current Draw: The 5V BEC supplies up to 2A continuous (shared with 4.5V rail total). High-torque servos or multiple servos under load can exceed this limit. Monitor current draw and consider external BEC if needed.

GPS/Compass Connector (6-pin JST-SH)

Location: Top side, bottom edge, right (solder pads on opposite side of the board)
Connector Type: 6-pin JST-SH

Pin	Label	Signal	STM32 Pin	Voltage	Function
1	4V5	Power	-	4.5V @ 2A	GPS/compass module power (USB or VBAT)
2	G	GND	-	Ground	Common ground
3	R8	RX	PE0	3.3V UART	GPS data input (UART8 RX)
4	T8	TX	PE1	3.3V UART	GPS data output (UART8 TX)
5	SDA	I2C Data	PB7	3.3V I2C	Compass data (I2C4 SDA)
6	SCL	I2C Clock	PB6	3.3V I2C	Compass clock (I2C4 SCL)

Configuration:

ArduPilot: SERIAL8_PROTOCOL = 5 (GPS), I2C compass auto-detected
Betaflight: Ports tab → GPS on UART8, Compass auto-detected on I2C4

Compatible GPS Modules:

u-blox M8 (2014 generation, budget-friendly)
u-blox M9 (2019 generation, improved accuracy)
u-blox M10 (2020+ generation, fastest fix times - recommended)
GPS + Compass combo (e.g., Holybro M9N, Matek M10-5883)

Compass Recommended for ArduPilot: While ArduPilot allows compass-less operation in certain modes (e.g., GUIDED_NOGPS for companion computer control), a compass or alternative heading source is typically required for proper navigation and autonomous operation. The H7-Digital has no onboard compass. Use a GPS/compass combo module for full functionality.

USB Power for Bench Testing: The GPS connector is powered from the 4.5V rail (5V BEC or USB). You can test GPS lock and compass calibration via USB power alone (no battery required).

I2C Pull-ups: The board includes on-board I2C pull-up resistors. If using long cables (>30cm) or multiple I2C devices, you may need to adjust I2C speed to 400kHz (see I2C Ports).

VTX (Video Transmitter) Connector (6-pin JST-SH)

Location: Top side, bottom edge, left (solder pads on opposite side of the board)
Connector Type: 6-pin JST-SH

Pin	Label	Signal	STM32 Pin	Voltage	Function
1	10V	Power	-	10V @ 2A	VTX power (software-controlled)
2	G	GND	-	Ground	Common ground
3	T2	TX	PA2	3.3V UART	MSP DisplayPort to VTX (UART2 TX)
4	R2	RX	PA3	3.3V UART	VTX telemetry (UART2 RX)
5	G	GND	-	Ground	Additional ground
6	R7	RX	PE7	3.3V UART	DJI SBUS input (UART7 RX, optional)

Configuration:

ArduPilot: SERIAL2_PROTOCOL = 42 (MSP DisplayPort), OSD_TYPE = 5
Betaflight: Ports tab → MSP on UART2, OSD configured automatically

Supported Digital HD Systems:

✓ OpenIPC (MSP DisplayPort)
✓ DJI (MSP DisplayPort + R7 for DJI SBUS)
✓ Walksnail/Avatar (MSP DisplayPort)
✓ HDZero (MSP DisplayPort)

10V Power Control: The 10V BEC can be toggled ON/OFF via software:

ArduPilot: RELAY2 (GPIO 80) - assign to RC switch via RCx_OPTION = 34 (Relay2 On/Off)

Betaflight: PINIO1 (“10V BEC”) - select “10V BEC” mode in Modes tab to assign to RC switch

Default state: ON (HIGH)

10V is VTX Only: Do NOT connect 5V peripherals to the 10V rail. Damage will occur. Use 10V exclusively for digital HD VTX power.

DJI SBUS Input (R7):

For DJI goggles with integrated receiver (e.g., DJI FPV Goggles V2):

Connect DJI SBUS output to R7 (pin 6)
Disable UART4 RC input: SERIAL4_PROTOCOL = 0
Enable UART7: SERIAL7_PROTOCOL = 23 (RC Input)

Companion Computer Connector (4-pin JST-SH)

Location: Top side, left edge
Connector Type: 4-pin JST-SH

Pin	Label	Signal	STM32 Pin	Voltage	Function
1	NC	Not Connected	-	-	Reserved (no power on this pin)
2	G	GND	-	Ground	Common ground
3	R5	RX	PB12	3.3V UART	Companion TX → FC RX (UART5 RX)
4	T5	TX	PB13	3.3V UART	FC TX → Companion RX (UART5 TX)

Configuration:

ArduPilot: SERIAL5_PROTOCOL = 2 (MAVLink2), SERIAL5_BAUD = 115 (115200 baud)
Betaflight: Not typically used (ArduPilot feature)

Typical Baud Rates:

115200 - Default, reliable for most applications
921600 - High-bandwidth for vision processing, object detection, or high-rate telemetry (requires good cables, short runs <30cm)

Compatible Companion Computers:

Raspberry Pi (Zero 2 W, 3/4/5)
NVIDIA Jetson (Nano, Orin Nano)
Orange Pi, Banana Pi, etc.

Power Not Provided: This connector does not supply power. It is recommended (and best practice) to power your companion computer separately (from main battery via BEC or USB power).

Voltage Level Shifting: The H7-Digital uses 3.3V UART signals. Most Raspberry Pi GPIO is 3.3V native, so direct connection is safe. Verify your companion computer’s UART voltage before connecting.

High-Bandwidth Applications: For high-bandwidth applications (computer vision, object detection, etc.), configure UART5 to 921600 baud. Use short, high-quality cables (≤30cm) and ensure proper shielding to prevent signal degradation.

Wiring Example (Raspberry Pi):

H7-Digital          Raspberry Pi
---------           ------------
Pin 2 (G)    →      Pin 6 (GND)
Pin 3 (R5)   →      Pin 8 (GPIO14, TX)
Pin 4 (T5)   →      Pin 10 (GPIO15, RX)

See ArduPilot Companion Computer Documentation for detailed configuration.

USB-C Connector

Location: Top side, right edge
Connector Type: USB Type-C

Capabilities:

USB 2.0 Full Speed (12 Mbps)
Firmware flashing via DFU mode
Ground station connection (Mission Planner, QGroundControl, Betaflight Configurator)
5V power input (for bench testing without battery)

Supported Use Cases:

Configuration and tuning
Blackbox log download
Firmware updates (APJ/HEX files)
Real-time telemetry and monitoring

USB Power Limitation: USB provides only ~500mA. Sufficient for FC + minimal peripherals powered off of the 4.5V pads. Always use battery power for full system testing.

Motor Outputs (M1-M8)

Motor Pin Assignments

Output	STM32 Pin	Timer	DMA	BiDir DShot (BetaFlight)	BiDir DShot (ArduPilot)	Group
M1	PE9	TIM1_CH1	✓	✓	✓	1
M2	PE11	TIM1_CH2	✓	✓	✗	1
M3	PE13	TIM1_CH3	✓	✓	✓	1
M4	PE14	TIM1_CH4	✓	✓	✗	1
M5	PD12	TIM4_CH1	✓	✓	✓	2
M6	PD13	TIM4_CH2	✓	✓	✗	2
M7	PD14	TIM4_CH3	✓	✓	✓	2
M8	PD15	TIM4_CH4	✗	✗	✗	2

Motor Numbering Convention

Standard quadcopter motor numbering (for Betaflight “Quad X” layout):

Quadcopter X motor layout diagram showing motor positions M1 (front-right), M2 (back-left), M3 (front-left), M4 (back-right) with rotation directions and flight controller orientation

Output Group Restrictions: All motors in the same group must use the same protocol.

Group 1 (M1-M4): Must match

Group 2 (M5-M8): Must match

Group 3 (S1-S2): Must match

Bidirectional DShot Support

Quick Reference:

Betaflight: M1-M7 support bidirectional DShot (M8 lacks DMA)
ArduPilot: M1, M3, M5, M7 only (timer channels CH1/CH3)

For complete details on bidirectional DShot vs UART ESC telemetry, protocol requirements, ESC compatibility, and configuration, see Understanding ESC Telemetry Methods below.

Servo Outputs (S1-S2)

Servo Pin Assignments

Output	STM32 Pin	Timer	DMA (ArduPilot)	DMA (BetaFlight)	Group	Connector
S1	PC6	TIM3_CH1	✓	✗	3	SRVO Pin 3
S2	PC7	TIM3_CH2	✓	✗	3	SRVO Pin 4

Servo DMA Configuration:

ArduPilot: Servo outputs use DMA for efficient PWM generation

Betaflight: Servo outputs explicitly disable DMA to free DMA resources for motor outputs and bidirectional DShot

Use Cases:

Camera gimbal control (pan/tilt)
Landing gear deployment
Parachute release
Cargo drop mechanisms
Any standard servo (50Hz PWM)

Understanding ESC Telemetry Methods

The H7-Digital supports three methods for receiving ESC telemetry data. Understanding the differences helps you choose the right method for your application.

Method 1: UART-Based ESC Telemetry (Traditional)

Connection: Dedicated telemetry wire from ESC to UART3 RX (Pin 4 on ESC connector)

How It Works:

ESC sends telemetry data via dedicated UART wire
Provides comprehensive data: RPM, voltage, current, temperature, mAh consumed
Update rate: 10Hz default, configurable up to 100Hz maximum

Supported ESC Firmware:

✅ BLHeli_32 (with telemetry wire connected)
✅ AM32 (with telemetry wire connected)
✅ BLHeli_S (firmware supports protocol, but many ESCs don’t wire telemetry pin)

Check ESC Hardware: Many BLHeli_S ESCs do not have the telemetry wire physically connected internally, even if the firmware supports the telemetry protocol. Always verify your specific ESC hardware specifications before expecting UART telemetry.

Configuration:

ArduPilot:

SERIAL5_PROTOCOL = 16        (ESC Telemetry)
SERVO_BLH_TRATE = 10         (Telemetry rate in Hz, default 10, max 100)

Betaflight:

Ports tab → Enable “ESC” on UART3
ESC/Motor tab → ESC Telemetry enabled

Advantages:

✅ Works with all DShot speeds (150/300/600)
✅ Comprehensive telemetry data (voltage, current, temp, mAh)
✅ Lower CPU overhead (interrupt-based, no DMA needed)
✅ Compatible with more ESC hardware

Disadvantages:

❌ Requires dedicated telemetry wire
❌ Lower update rate (10-100Hz vs 400Hz for bidirectional)
❌ Many BLHeli_S ESCs don’t physically wire the telemetry pin

Method 2: Bidirectional DShot (Modern)

Connection: Uses motor signal wires for both commands (TX) and telemetry (RX)

How It Works:

Motor signal wire carries bidirectional communication
ESC responds with RPM data between command pulses
No dedicated telemetry wire needed

Supported ESC Firmware:

✅ BLHeli_32 v32.7+
✅ AM32
✅ BLHeli_S with BlueJay or JazzMaverick firmware
❌ Stock BLHeli_S (not supported)

Protocol Requirements:

Requires DShot300 or higher (DShot150 too slow for bidirectional timing)
DShot300 or DShot600 recommended
DShot1200 supported but not recommended (removed from Betaflight 4.1+, minimal ArduPilot testing)

Why DShot300/600? DShot150 has insufficient pulse width for the ESC to respond with telemetry data within the timing window. DShot300 and DShot600 provide adequate timing margins. DShot1200 is technically possible but has poor ESC support and stability issues.

H7-Digital Motor Support:

Motor	Pin	Timer	ArduPilot BiDir	Betaflight BiDir	Notes
M1	PE9	TIM1_CH1	✅	✅	Full support
M2	PE11	TIM1_CH2	❌	✅	ArduPilot limitation (CH2)
M3	PE13	TIM1_CH3	✅	✅	Full support
M4	PE14	TIM1_CH4	❌	✅	ArduPilot limitation (CH4)
M5	PD12	TIM4_CH1	✅	✅	Full support
M6	PD13	TIM4_CH2	❌	✅	ArduPilot limitation (CH2)
M7	PD14	TIM4_CH3	✅	✅	Full support
M8	PD15	TIM4_CH4	❌	❌	No DMA - Not supported

ArduPilot Limitation Explained: ArduPilot’s bidirectional DShot implementation only supports timer channels CH1 and CH3 (M1, M3, M5, M7) due to DMA allocation strategy. Bidirectional DShot cannot use complementary timer channels (CH1N, CH2N, CH3N, CH4N) which are hardware-paired with main channels on STM32 Advanced Timers. CH2 and CH4 share DMA resources in ways that prevent reliable bidirectional communication. Betaflight uses more aggressive DMA sharing and supports M1-M7 (all except M8, which has no DMA).

Configuration:

ArduPilot:

MOT_PWM_TYPE = 4             (DShot300)  OR
MOT_PWM_TYPE = 5             (DShot600)  [Recommended]
SERVO_BLH_BDMASK = 85        (Binary: 01010101 = M1,M3,M5,M7)

Betaflight:

ESC/Motor tab → Enable “Bidirectional DShot”
Ports tab → Note: UART DMA disabled by default when BiDir DShot enabled

Betaflight DMA Conflict: Enabling bidirectional DShot in Betaflight disables UART DMA by default to avoid DMA resource conflicts. This prioritizes bidirectional DShot (400Hz motor telemetry) over UART DMA.

Advantages:

✅ No dedicated telemetry wire needed (cleaner wiring)
✅ Higher update rate (up to 400Hz RPM data)
✅ Better for dynamic notch filtering and RPM-based features
✅ Industry standard for modern racing/freestyle setups

Disadvantages:

❌ Requires DShot300+ (can’t use DShot150)
❌ RPM data only (no voltage/current/temp from ESC) - unless using Extended DShot Telemetry (see Method 3)
❌ Not all ESCs support it (stock BLHeli_S doesn’t)
❌ ArduPilot limited to M1/M3/M5/M7 only
❌ In Betaflight, enabling BiDir DShot disables UART DMA by default

Method 3: Extended DShot Telemetry (EDT) - Best of Both Worlds

Connection: Uses motor signal wires (same as bidirectional DShot)

How It Works:

Expands bidirectional DShot to transmit additional sensor data alongside RPM
ESCs without dedicated telemetry UART can report voltage, current, temperature, and diagnostics
All data transmitted through the motor signal wire
No dedicated telemetry wire needed

What is EDT?

Extended DShot Telemetry (EDT) enables ESCs to transmit comprehensive telemetry data over the motor signal wire, combining the high update rate of bidirectional DShot with the rich data of UART telemetry.

EDT Versions:

EDTv1: Adds voltage, current, and temperature to RPM data

EDTv2: Includes advanced diagnostics:

ESC status events (stress level, stall, desync)
Demagnetization and cross-sequence anomaly detection

Data Provided:

✅ RPM (400Hz update rate, like standard bidirectional DShot)
✅ Voltage (like UART telemetry)
✅ Current (like UART telemetry) *
✅ Temperature (like UART telemetry)
✅ Advanced diagnostics (EDTv2):
- ESC stress level
- Stall events
- Desync events
- Demagnetization detection
- Cross-sequence anomalies

Current Telemetry on 4-in-1 ESCs: Current measurement typically unavailable on 4-in-1 ESCs due to single shared current sensor (not per-ESC). Individual ESCs may support per-ESC current measurement.

Supported ESC Firmware:

Firmware	Minimum Version	EDT Version	Notes
BlueJay (8-bit)	v0.19.2+	EDTv1	Recommended stable
BlueJay (8-bit)	v0.20.1-RC2+	EDTv2	Testing, includes advanced diagnostics
AM32 (32-bit)	v2.04+	EDTv1/v2	Full EDT support
BLHeli_32 (32-bit)	v32.9+	EDTv1	Not recommended (reported issues)
Stock BLHeli_S	N/A	❌	Not supported (use BlueJay alternative firmware)

BLHeli_32 EDT Issues: While BLHeli_32 v32.9+ added EDT support, it has reported issues. BlueJay and AM32 are recommended for reliable EDT operation.

Protocol Requirements:

Requires bidirectional DShot (DShot300+ recommended)
Same motor limitations as bidirectional DShot:
- ArduPilot: M1, M3, M5, M7 only (CH1/CH3 timer channels)
- Betaflight: M1-M7 (M8 no DMA)

Configuration:

ArduPilot:

MOT_PWM_TYPE = 4 or 5        (DShot300 or DShot600)
SERVO_BLH_BDMASK = 85        (Enable bidirectional on M1,M3,M5,M7)

EDT data automatically logged as EDT2 messages in flight logs (no additional config needed).

Betaflight:

ESC/Motor tab → Enable “Bidirectional DShot”
EDT data automatically detected and logged if ESC supports it
No additional configuration required

Automatic Operation: EDT operates transparently. If your ESC firmware supports EDT, the flight controller will automatically receive and log the extended telemetry data. No special configuration beyond enabling bidirectional DShot is required.

Advantages:

✅ Best of both worlds: High RPM rate (400Hz) + comprehensive data (voltage/current/temp)
✅ No dedicated telemetry wire needed (cleaner wiring)
✅ Advanced diagnostics for troubleshooting (stress, stalls, desyncs, demag)
✅ Ideal for performance analysis and ESC health monitoring
✅ Good firmware support (BlueJay, AM32)

Disadvantages:

❌ Requires DShot300+ (can’t use DShot150)
❌ ArduPilot limited to M1/M3/M5/M7 only (bidirectional DShot limitation)
❌ Not supported on stock BLHeli_S (requires BlueJay alternative firmware)
❌ BLHeli_32 EDT support has reported issues (use AM32 or BlueJay instead)
❌ Current telemetry typically unavailable on 4-in-1 ESCs (shared current sensor)
❌ Telemetry sent on “best efforts” basis (not guaranteed delivery)

When to Use EDT:

✅ You have BlueJay v0.19.2+ or AM32 v2.04+ ESCs
✅ You want comprehensive telemetry without extra wiring
✅ You prioritize both performance (400Hz RPM) and diagnostics (voltage/temp/current)
✅ You’re building a new quad and can choose EDT-compatible ESCs

Recommended Approach: For new builds, choose ESCs with AM32 v2.04+ or flash BLHeli_S ESCs with BlueJay v0.19.2+ firmware. EDT provides the benefits of both UART and bidirectional DShot telemetry in a single protocol - the best of both worlds.

Comparison Table

Feature	UART ESC Telemetry	Bidirectional DShot	Extended DShot Telemetry (EDT)
Wiring	Dedicated telemetry wire	Motor signal wire only	Motor signal wire only
Data Provided	RPM, voltage, current, temp, mAh	RPM only	RPM, voltage, current, temp, diagnostics
Update Rate	10-100Hz	Up to 400Hz	Up to 400Hz (RPM)
DShot Speed	All (150/300/600)	DShot300+ only	DShot300+ only
ESC Support	BLHeli_32, AM32, BLHeli_S*	BLHeli_32, AM32, BLHeli_S (BlueJay/JazzMaverick)	BlueJay v0.19.2+, AM32 v2.04+, BLHeli_32 v32.9+ (issues)
CPU Overhead	Low (interrupt-based)	Moderate (DMA-based)	Moderate (DMA-based)
ArduPilot Motors	All motors	M1, M3, M5, M7 only	M1, M3, M5, M7 only
Betaflight Motors	All motors	M1-M7 (M8 no DMA)	M1-M7 (M8 no DMA)
Special Notes	Many BLHeli_S ESCs don’t wire telemetry pin	Standard for modern racing/freestyle	Current unavailable on 4-in-1 ESCs
Best For	Autonomous flight, all-motor telemetry	Racing, freestyle, dynamic filtering	New builds wanting best of both worlds

*Many BLHeli_S ESCs don’t physically wire the telemetry pin

Which Method Should I Use?

Choose Extended DShot Telemetry (EDT) if: ⭐ Best option for new builds

✅ You have BlueJay v0.19.2+ or AM32 v2.04+ ESCs (or can flash BlueJay)
✅ You want both high RPM rate (400Hz) and comprehensive data (voltage/temp/current)
✅ You want cleaner wiring without telemetry wire
✅ You’re building a new quad and can choose EDT-compatible ESCs
✅ You want advanced diagnostics (stress, stalls, desyncs)

Choose UART ESC Telemetry if:

✅ You’re using DShot150 (long cable runs, noise immunity)
✅ Your ESC supports UART telemetry and wire is connected
✅ You need telemetry on all motors (ArduPilot: M1-M8, not just M1/M3/M5/M7)
✅ You’re running ArduPilot on a non-quad (M2/M4/M6 needed for motors)
✅ You want lower CPU overhead
✅ Your ESCs don’t support EDT (older BLHeli_32, stock BLHeli_S)

Choose Bidirectional DShot (RPM only) if:

✅ You only need RPM data (don’t need voltage/current/temp)
✅ You want maximum RPM telemetry rate (400Hz for dynamic filtering)
✅ You prefer cleaner wiring (no telemetry wire)
✅ You’re using ESCs that support BiDir but not EDT
✅ You prioritize flight performance over battery monitoring
✅ You’re building a racing or freestyle quad (EDT is better if ESCs support it)

Cannot Use UART and Bidirectional/EDT Simultaneously: Choose one telemetry method. Enabling both will cause conflicts. EDT is an extension of bidirectional DShot, so enabling BiDir DShot with EDT-compatible ESCs automatically provides EDT data.

Performance Comparison

UART ESC Telemetry:

Update rate: 10Hz default, 100Hz maximum
CPU overhead: Low (interrupt-based reception, no DMA)
Data richness: High (RPM + voltage + current + temp + mAh)
Best for: Autonomous flight, long-range, battery monitoring, all-motor telemetry

Bidirectional DShot (RPM only):

Update rate: 400Hz (4x faster than UART max)
CPU overhead: Moderate (DMA-based communication)
Data richness: Low (RPM only)
Best for: Racing, freestyle, aggressive dynamic filtering when voltage/temp not needed

Extended DShot Telemetry (EDT): ⭐ Recommended for new builds

Update rate: 400Hz (RPM), periodic (voltage/current/temp)
CPU overhead: Moderate (DMA-based communication, same as BiDir DShot)
Data richness: Very high (RPM + voltage + current + temp + advanced diagnostics)
Best for: Modern racing/freestyle builds, performance analysis, comprehensive monitoring with clean wiring

External Resources

For detailed configuration, parameters, and troubleshooting:

ArduPilot ESC Telemetry Documentation
Betaflight ESC Firmware Guide - EDT information
Betaflight Bidirectional DShot Setup

I2C Ports

I2C Pin Assignments

Port	SCL Pin	SDA Pin	Usage	Connector	Default Speed
I2C1	PB8	PB9	Internal	Barometer (on-board)	400kHz (AP), 800kHz (BF)
I2C4	PB6	PB7	External	GPS connector	400kHz (AP), 800kHz (BF)

Connected Devices:

I2C1: DPS368 barometer (address 0x76)
I2C4: External compass (address varies by model)

If experiencing I2C sensor detection issues in Betaflight, reduce speed to 400kHz via CLI:
set i2c1_clockspeed_khz = 400
set i2c4_clockspeed_khz = 400

SPI Ports

SPI1 (Internal IMU)

Signal	Pin	Usage
SCK	PA5	Clock
MISO	PA6	Master In Slave Out
MOSI	PA7	Master Out Slave In
CS	PB0	Chip Select (IMU)

Connected Device:

ICM-42688-P 6-axis IMU (gyro + accelerometer)

SPI1 is dedicated to the IMU. Do not attempt to connect external SPI devices without proper hardware modification and firmware changes.

ADC Inputs (Analog Sensing)

ADC	Pin	Function	Scaling
ADC1	PA0	Battery Voltage	11.0:1 divider
ADC2	PA1	Battery Current	18.0 mV/A

Battery Monitoring Configuration:

ArduPilot: BATT_MONITOR = 4, BATT_VOLT_PIN = 16, BATT_CURR_PIN = 17
Betaflight: Automatic detection, scales configurable in Power tab

GPIO and Special Functions

Status LEDs

LED	Color	Pin	Function
LED0	Blue	PD8	Primary flight status
LED1	Green	PB15	Secondary status (armed indicator)
LED2	Amber	PB14	Tertiary status (DFU mode indicator)

See LED Quick Reference in Specifications for detailed LED pattern meanings.

VTX Power Control

Function	Pin	Default	Control
10V BEC Enable	PE2	ON (HIGH)	ArduPilot: RELAY2 (GPIO 80), Betaflight: PINIO1 (“10V BEC”)

Configuration:

ArduPilot: Assign to RC channel via RCx_OPTION = 34 (Relay2 On/Off)
Betaflight: Select “10V BEC” mode in Modes tab to assign to RC switch

BOOT Button

Function	Pin	Usage
Enter DFU Mode	BOOT0	Hold during power-on to enter firmware flashing mode

Board Orientation and Mounting

Board Orientation

The forward arrow on the board indicates aircraft forward direction.

Default IMU Orientation (in firmware):

ArduPilot: ROLL_180_YAW_90
Betaflight: Configured in Board Alignment tab if needed

If you mount the flight controller in a non-standard orientation (rotated or inverted), you must configure the board alignment in your firmware to match your physical installation.

Mounting Pattern

Specification	Measurement
Board Size	41mm × 41mm
Mounting Holes	M3 (4 holes)
Mounting Pattern	30.5mm (standard 30.5mm stack spacing)

Always use soft-mount dampers (included) to isolate the flight controller from frame vibrations. Hard mounting can cause gyroscope noise and degraded flight performance.

Wiring Best Practices

Cable Routing

Keep signal wires short - Minimize EMI pickup
Separate power and signal - Route high-current wires away from UART/I2C
Use twisted pairs - Twist TX/RX pairs together for better noise immunity
Secure connections - Use hot glue or zip ties to prevent vibration-induced disconnects
Strain relief - Don’t put tension on connector solder joints

Solder Pads (Alternate Connections)

The H7-Digital provides solder pads for all connectors for builders who prefer direct soldering or custom cable routing.

Available as Pads:

RC: adjacent to connector
SRVO: adjacent to connector
COMPUTER: adjacent to connector
ESC: adjacent to connector
M5+: adjacent to connector
VTX: 6-pin JST-SH pads (bottom edge, left)
GPS/Compass: 6-pin JST-SH pads (bottom edge, right)

When to Use Solder Pads:

Custom cable lengths or routing
Weight reduction (no connectors)
Permanent installation (no disconnection needed)
Space-constrained builds

When to Use Pre-installed Connectors:

Standard cables available
Frequent disassembly/reassembly
No soldering skills/equipment
Rapid prototyping

Troubleshooting Connection Issues

Symptom	Likely Cause	Solution
No GPS fix	TX/RX swapped	Swap R8 and T8 connections
No RC input	Wrong UART protocol	Verify UART4 protocol = 23 (ArduPilot) or enabled in Betaflight
OSD not showing	VTX not powered or wrong UART	Check 10V enabled, verify UART2 = DisplayPort
ESC not arming	Motor signal issue	Check motor protocol (DShot), verify ESC calibration
Compass not detected	I2C speed too high	Reduce I2C4 to 400kHz in CLI

Connector Standard

JST-SH Series

The H7-Digital uses JST-SH connectors exclusively, adhering to the BetaFlight Connector Standard.

Advantages:

✓ No soldering required for most connections
✓ Standardized pinouts across manufacturers
✓ Small form factor (1mm pitch)
✓ Wide availability of compatible cables

Connector Types Used:

8-pin JST-SH - ESC (M1-M4 motors)
6-pin JST-SH - Motors 5-8, GPS, VTX
4-pin JST-SH - RC Input, Companion Computer, Servos

Cable Compatibility: All JST-SH cables following the BetaFlight standard will work with the H7-Digital. Look for “Betaflight-compatible” or BetaFlight logo when purchasing cables.

Cable Compatibility Matrix

Pre-Made Cable Sources

Cable Type	Compatibility
JST-SH to JST-SH 8-pin	Included with H7-Digital
JST-SH 4-pin	RC receivers, servos
JST-SH 6-pin	GPS, VTX modules
JST-SH 8-pin	4-in-1 ESCs

Specifications - Complete technical specifications
Power System - Power architecture and battery monitoring
Sensors - IMU, barometer, and external sensor details

External Resources

BetaFlight Connector Standard - Official JST-SH pinout standard
ArduPilot Serial Port Configuration - UART protocol setup
Betaflight Ports Configuration - Ports tab guide

Support

For pinout and connector questions:

Email: support@aerocogito.com

Pinout & Connectors

Table of Contents

Quick Reference

Board Specifications

Pinout Diagrams

UART Mapping

Complete UART Reference

ArduPilot Protocol Numbers

Power System

Battery Input

Regulated Power Outputs

Connectors

ESC Connector (8-pin JST-SH)

Motors 5-8 Connector (6-pin JST-SH)

RC Input Connector (4-pin JST-SH)

Servos Connector (4-pin JST-SH)

GPS/Compass Connector (6-pin JST-SH)

VTX (Video Transmitter) Connector (6-pin JST-SH)

Companion Computer Connector (4-pin JST-SH)

USB-C Connector

Motor Outputs (M1-M8)

Motor Pin Assignments

Motor Numbering Convention

Bidirectional DShot Support

Servo Outputs (S1-S2)

Servo Pin Assignments

Understanding ESC Telemetry Methods

Method 1: UART-Based ESC Telemetry (Traditional)

Method 2: Bidirectional DShot (Modern)

Method 3: Extended DShot Telemetry (EDT) - Best of Both Worlds

Comparison Table

Which Method Should I Use?

Performance Comparison

External Resources

I2C Ports

I2C Pin Assignments

SPI Ports

SPI1 (Internal IMU)

ADC Inputs (Analog Sensing)

GPIO and Special Functions

Status LEDs

VTX Power Control

BOOT Button

Board Orientation and Mounting

Board Orientation

Mounting Pattern

Wiring Best Practices

Cable Routing

Solder Pads (Alternate Connections)

Troubleshooting Connection Issues

Connector Standard

JST-SH Series

Cable Compatibility Matrix

Pre-Made Cable Sources

Related Documentation

External Resources

Support