Fix RadiolinkF405 ESC_SENSOR_UART

[ot0tot]

BF 4.5 builds were failing because this was UART3, not USART3.

Summary by CodeRabbit

• Chores
  • Updated the configuration to use a revised identifier for the ESC sensor communication port.

[coderabbitai]

Walkthrough

The macro defining the UART port used for the ESC sensor in the RADIOLINKF405 configuration was updated from SERIAL_PORT_UART3 to SERIAL_PORT_USART3, reflecting a change in the identifier for the serial peripheral assigned to ESC sensor communication.

Changes

File(s)	Change Summary
configs/RADIOLINKF405/config.h	Updated macro for ESC sensor UART from UART3 to USART3

Estimated code review effort

1 (~2 minutes)

Possibly related PRs

• HUMMINGBIRD_AIO_255 remove ESC uart define #837: Modifies the ESC_SENSOR_UART macro in configuration headers for a different board, related by the same macro.
• Add RADIOLINKF405 target #834: Adds the original RADIOLINKF405 config file with the UART3 assignment; this PR updates that setting.

Suggested reviewers

• haslinghuis
• nerdCopter

---

📜 Recent review details

Configuration used: .coderabbit.yaml
Review profile: CHILL
Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between fd8cd85 and 0813817.

📒 Files selected for processing (1)

• configs/RADIOLINKF405/config.h (1 hunks)

🧠 Learnings (2)

📓 Common learnings

Learnt from: ot0tot
PR: betaflight/config#834
File: configs/RADIOLINKF405/config.h:54-54
Timestamp: 2025-07-14T15:38:58.935Z
Learning: ESC sensor communication in Betaflight is unidirectional and only requires the UART RX pin. It does not need bidirectional communication, so UART_TX_PIN definitions are not required for ESC sensor UARTs. Some flight controller boards may not even expose the TX pin for the UART designated for ESC sensor use.

Learnt from: ot0tot
PR: betaflight/config#834
File: configs/RADIOLINKF405/config.h:52-53
Timestamp: 2025-07-14T15:38:06.837Z
Learning: In Betaflight flight controller configurations, it's common and intentional for UART2_RX_PIN and RX_PPM_PIN to share the same GPIO pin (like PA3) because they represent mutually exclusive receiver input protocols. The pin can be configured for either serial receiver input (UART2) or PPM input, but not both simultaneously. This is a standard design pattern in flight controller hardware.

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in each config.h matches the directory name it resides in (e.g., configs/AXISFLYINGF7AIO/config.h must have #define BOARD_NAME AXISFLYINGF7AIO). This check is required for all Betaflight board configuration reviews.

Learnt from: haslinghuis
PR: betaflight/config#822
File: configs/AXISFLYINGH7MINI/config.h:121-129
Timestamp: 2025-06-23T18:44:59.162Z
Learning: In Betaflight configuration files, USE_OSD_HD and USE_MAX7456 are for different OSD systems: USE_MAX7456 enables the MAX7456 analog OSD chip, while USE_OSD_HD enables HD/digital OSD via MSP. MSP_DISPLAYPORT_UART should be guarded by USE_OSD_HD, not USE_MAX7456, as they serve different OSD implementations.

Learnt from: haslinghuis
PR: betaflight/config#822
File: configs/AXISFLYINGH7MINI/config.h:29-37
Timestamp: 2025-06-23T18:43:31.746Z
Learning: In Betaflight configuration files, feature enablement macros like USE_MAG are build options that can be controlled at compile time, while hardware instance definitions like MAG_I2C_INSTANCE are predefined in board configurations to assist with hardware mapping when those features are enabled at build time.

Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T15:17:30.040Z
Learning: In Betaflight configurations, when a target name suggests dual IMUs (like JHEF7DUAL) but specific hardware variants only have one gyro available, the preferred solution is to use DEFAULT_GYRO_TO_USE macro to specify which gyro to use by default rather than pruning gyro defines or creating redundant configurations. This approach maintains compatibility when the same target is used by multiple hardware variants from the same manufacturer.

Learnt from: ot0tot
PR: betaflight/config#681
File: configs/NYX405V1/config.h:26-28
Timestamp: 2025-07-14T15:47:16.394Z
Learning: In Betaflight configuration files, MANUFACTURER_ID values must be exactly 4 ASCII characters long, not 3 characters. All manufacturer IDs in the codebase consistently use 4-character identifiers like AIRB, FOSS, SPBE, MTKS, NERC, etc.

Learnt from: haslinghuis
PR: betaflight/config#792
File: configs/FLYWOOF411/config.h:33-33
Timestamp: 2025-05-28T15:48:18.449Z
Learning: The FLYWOOF411 board does not actually use dual gyros despite having GYRO_2_SPI_INSTANCE defined in its configuration. It was incorrectly targeted for GYRO_COUNT and dual gyro support.

Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-06-02T16:16:20.197Z
Learning: In STM32F405-based flight controller configurations, timer pin mappings must be carefully analyzed for DMA stream conflicts, especially between motor timers, LED strip timers, and SPI DMA assignments. Changes to TIMER_PIN_MAPPING should include verification that all required peripherals (motors, LED strip, blackbox SPI) can coexist without DMA conflicts.

configs/RADIOLINKF405/config.h (11)

Learnt from: ot0tot
PR: #834
File: configs/RADIOLINKF405/config.h:54-54
Timestamp: 2025-07-14T15:38:58.935Z
Learning: ESC sensor communication in Betaflight is unidirectional and only requires the UART RX pin. It does not need bidirectional communication, so UART_TX_PIN definitions are not required for ESC sensor UARTs. Some flight controller boards may not even expose the TX pin for the UART designated for ESC sensor use.

Learnt from: haslinghuis
PR: #822
File: configs/AXISFLYINGH7MINI/config.h:121-129
Timestamp: 2025-06-23T18:44:59.162Z
Learning: In Betaflight configuration files, USE_OSD_HD and USE_MAX7456 are for different OSD systems: USE_MAX7456 enables the MAX7456 analog OSD chip, while USE_OSD_HD enables HD/digital OSD via MSP. MSP_DISPLAYPORT_UART should be guarded by USE_OSD_HD, not USE_MAX7456, as they serve different OSD implementations.

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in each config.h matches the directory name it resides in (e.g., configs/AXISFLYINGF7AIO/config.h must have #define BOARD_NAME AXISFLYINGF7AIO). This check is required for all Betaflight board configuration reviews.

Learnt from: ot0tot
PR: #834
File: configs/RADIOLINKF405/config.h:52-53
Timestamp: 2025-07-14T15:38:06.837Z
Learning: In Betaflight flight controller configurations, it's common and intentional for UART2_RX_PIN and RX_PPM_PIN to share the same GPIO pin (like PA3) because they represent mutually exclusive receiver input protocols. The pin can be configured for either serial receiver input (UART2) or PPM input, but not both simultaneously. This is a standard design pattern in flight controller hardware.

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in config.h files exactly matches the directory name where the config file is located. For example, if the config file is in configs/AXISFLYINGF7AIO/config.h, then the BOARD_NAME should be defined as "AXISFLYINGF7AIO". This ensures proper board identification and configuration loading in Betaflight.

Learnt from: haslinghuis
PR: #822
File: configs/AXISFLYINGH7MINI/config.h:29-37
Timestamp: 2025-06-23T18:43:31.746Z
Learning: In Betaflight configuration files, feature enablement macros like USE_MAG are build options that can be controlled at compile time, while hardware instance definitions like MAG_I2C_INSTANCE are predefined in board configurations to assist with hardware mapping when those features are enabled at build time.

Learnt from: haslinghuis
PR: #835
File: configs/HDZERO_HALO_MPU6000/config.h:44-56
Timestamp: 2025-07-14T16:16:56.822Z
Learning: For Betaflight board configurations of boards already in production, pin assignments in config.h files reflect the actual hardware design and cannot be changed, even if they present potential conflicts with debug interfaces. The configuration must match the physical board layout, not ideal software design preferences.

Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-06-02T16:16:20.197Z
Learning: In STM32F405-based flight controller configurations, timer pin mappings must be carefully analyzed for DMA stream conflicts, especially between motor timers, LED strip timers, and SPI DMA assignments. Changes to TIMER_PIN_MAPPING should include verification that all required peripherals (motors, LED strip, blackbox SPI) can coexist without DMA conflicts.

Learnt from: ot0tot
PR: #834
File: configs/RADIOLINKF405/config.h:79-88
Timestamp: 2025-07-14T15:41:14.364Z
Learning: In STM32F405 configurations, PB1 typically maps to TIM3_CH4 and PC9 typically maps to TIM8_CH4. These are different timers and do not share DMA resources, so there is no conflict when both pins are used simultaneously (e.g., PB1 for LED_STRIP and PC9 for MOTOR4).

Learnt from: haslinghuis
PR: #792
File: configs/MERAKRCF722/config.h:32-32
Timestamp: 2025-05-28T15:45:15.608Z
Learning: The presence of GYRO_2_SPI_INSTANCE definition in a board config does not necessarily mean the board uses dual gyros. Some boards have GYRO_2_SPI_INSTANCE defined but it's not actually used, so they should not receive GYRO_COUNT or other dual-gyro related definitions. Only boards that actually utilize dual gyros should get these definitions.

Learnt from: haslinghuis
PR: #798
File: configs/FURYF4OSD/config.h:88-88
Timestamp: 2025-05-31T17:01:39.423Z
Learning: For STM32F4xx platforms, PB1 pin timer definitions are:
1 = DEF_TIM(TIM1, CH3N, PB1, 0, 0)
2 = DEF_TIM(TIM3, CH4, PB1, 0, 0)
3 = DEF_TIM(TIM8, CH3N, PB1, 0, 0)
Timer instance 2 (TIM3, CH4) is the correct mapping for PB1 motor control on STM32F4xx platforms as defined in src/platform/STM32/timer_stm32f4xx.c

🧰 Additional context used

🧠 Learnings (2)

📓 Common learnings

Learnt from: ot0tot
PR: betaflight/config#834
File: configs/RADIOLINKF405/config.h:54-54
Timestamp: 2025-07-14T15:38:58.935Z
Learning: ESC sensor communication in Betaflight is unidirectional and only requires the UART RX pin. It does not need bidirectional communication, so UART_TX_PIN definitions are not required for ESC sensor UARTs. Some flight controller boards may not even expose the TX pin for the UART designated for ESC sensor use.

Learnt from: ot0tot
PR: betaflight/config#834
File: configs/RADIOLINKF405/config.h:52-53
Timestamp: 2025-07-14T15:38:06.837Z
Learning: In Betaflight flight controller configurations, it's common and intentional for UART2_RX_PIN and RX_PPM_PIN to share the same GPIO pin (like PA3) because they represent mutually exclusive receiver input protocols. The pin can be configured for either serial receiver input (UART2) or PPM input, but not both simultaneously. This is a standard design pattern in flight controller hardware.

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in each config.h matches the directory name it resides in (e.g., configs/AXISFLYINGF7AIO/config.h must have #define BOARD_NAME AXISFLYINGF7AIO). This check is required for all Betaflight board configuration reviews.

Learnt from: haslinghuis
PR: betaflight/config#822
File: configs/AXISFLYINGH7MINI/config.h:121-129
Timestamp: 2025-06-23T18:44:59.162Z
Learning: In Betaflight configuration files, USE_OSD_HD and USE_MAX7456 are for different OSD systems: USE_MAX7456 enables the MAX7456 analog OSD chip, while USE_OSD_HD enables HD/digital OSD via MSP. MSP_DISPLAYPORT_UART should be guarded by USE_OSD_HD, not USE_MAX7456, as they serve different OSD implementations.

Learnt from: haslinghuis
PR: betaflight/config#822
File: configs/AXISFLYINGH7MINI/config.h:29-37
Timestamp: 2025-06-23T18:43:31.746Z
Learning: In Betaflight configuration files, feature enablement macros like USE_MAG are build options that can be controlled at compile time, while hardware instance definitions like MAG_I2C_INSTANCE are predefined in board configurations to assist with hardware mapping when those features are enabled at build time.

Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T15:17:30.040Z
Learning: In Betaflight configurations, when a target name suggests dual IMUs (like JHEF7DUAL) but specific hardware variants only have one gyro available, the preferred solution is to use DEFAULT_GYRO_TO_USE macro to specify which gyro to use by default rather than pruning gyro defines or creating redundant configurations. This approach maintains compatibility when the same target is used by multiple hardware variants from the same manufacturer.

Learnt from: ot0tot
PR: betaflight/config#681
File: configs/NYX405V1/config.h:26-28
Timestamp: 2025-07-14T15:47:16.394Z
Learning: In Betaflight configuration files, MANUFACTURER_ID values must be exactly 4 ASCII characters long, not 3 characters. All manufacturer IDs in the codebase consistently use 4-character identifiers like AIRB, FOSS, SPBE, MTKS, NERC, etc.

Learnt from: haslinghuis
PR: betaflight/config#792
File: configs/FLYWOOF411/config.h:33-33
Timestamp: 2025-05-28T15:48:18.449Z
Learning: The FLYWOOF411 board does not actually use dual gyros despite having GYRO_2_SPI_INSTANCE defined in its configuration. It was incorrectly targeted for GYRO_COUNT and dual gyro support.

Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-06-02T16:16:20.197Z
Learning: In STM32F405-based flight controller configurations, timer pin mappings must be carefully analyzed for DMA stream conflicts, especially between motor timers, LED strip timers, and SPI DMA assignments. Changes to TIMER_PIN_MAPPING should include verification that all required peripherals (motors, LED strip, blackbox SPI) can coexist without DMA conflicts.

configs/RADIOLINKF405/config.h (11)

Learnt from: ot0tot
PR: #834
File: configs/RADIOLINKF405/config.h:54-54
Timestamp: 2025-07-14T15:38:58.935Z
Learning: ESC sensor communication in Betaflight is unidirectional and only requires the UART RX pin. It does not need bidirectional communication, so UART_TX_PIN definitions are not required for ESC sensor UARTs. Some flight controller boards may not even expose the TX pin for the UART designated for ESC sensor use.

Learnt from: haslinghuis
PR: #822
File: configs/AXISFLYINGH7MINI/config.h:121-129
Timestamp: 2025-06-23T18:44:59.162Z
Learning: In Betaflight configuration files, USE_OSD_HD and USE_MAX7456 are for different OSD systems: USE_MAX7456 enables the MAX7456 analog OSD chip, while USE_OSD_HD enables HD/digital OSD via MSP. MSP_DISPLAYPORT_UART should be guarded by USE_OSD_HD, not USE_MAX7456, as they serve different OSD implementations.

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in each config.h matches the directory name it resides in (e.g., configs/AXISFLYINGF7AIO/config.h must have #define BOARD_NAME AXISFLYINGF7AIO). This check is required for all Betaflight board configuration reviews.

Learnt from: ot0tot
PR: #834
File: configs/RADIOLINKF405/config.h:52-53
Timestamp: 2025-07-14T15:38:06.837Z
Learning: In Betaflight flight controller configurations, it's common and intentional for UART2_RX_PIN and RX_PPM_PIN to share the same GPIO pin (like PA3) because they represent mutually exclusive receiver input protocols. The pin can be configured for either serial receiver input (UART2) or PPM input, but not both simultaneously. This is a standard design pattern in flight controller hardware.

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in config.h files exactly matches the directory name where the config file is located. For example, if the config file is in configs/AXISFLYINGF7AIO/config.h, then the BOARD_NAME should be defined as "AXISFLYINGF7AIO". This ensures proper board identification and configuration loading in Betaflight.

Learnt from: haslinghuis
PR: #822
File: configs/AXISFLYINGH7MINI/config.h:29-37
Timestamp: 2025-06-23T18:43:31.746Z
Learning: In Betaflight configuration files, feature enablement macros like USE_MAG are build options that can be controlled at compile time, while hardware instance definitions like MAG_I2C_INSTANCE are predefined in board configurations to assist with hardware mapping when those features are enabled at build time.

Learnt from: haslinghuis
PR: #835
File: configs/HDZERO_HALO_MPU6000/config.h:44-56
Timestamp: 2025-07-14T16:16:56.822Z
Learning: For Betaflight board configurations of boards already in production, pin assignments in config.h files reflect the actual hardware design and cannot be changed, even if they present potential conflicts with debug interfaces. The configuration must match the physical board layout, not ideal software design preferences.

Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-06-02T16:16:20.197Z
Learning: In STM32F405-based flight controller configurations, timer pin mappings must be carefully analyzed for DMA stream conflicts, especially between motor timers, LED strip timers, and SPI DMA assignments. Changes to TIMER_PIN_MAPPING should include verification that all required peripherals (motors, LED strip, blackbox SPI) can coexist without DMA conflicts.

Learnt from: ot0tot
PR: #834
File: configs/RADIOLINKF405/config.h:79-88
Timestamp: 2025-07-14T15:41:14.364Z
Learning: In STM32F405 configurations, PB1 typically maps to TIM3_CH4 and PC9 typically maps to TIM8_CH4. These are different timers and do not share DMA resources, so there is no conflict when both pins are used simultaneously (e.g., PB1 for LED_STRIP and PC9 for MOTOR4).

Learnt from: haslinghuis
PR: #792
File: configs/MERAKRCF722/config.h:32-32
Timestamp: 2025-05-28T15:45:15.608Z
Learning: The presence of GYRO_2_SPI_INSTANCE definition in a board config does not necessarily mean the board uses dual gyros. Some boards have GYRO_2_SPI_INSTANCE defined but it's not actually used, so they should not receive GYRO_COUNT or other dual-gyro related definitions. Only boards that actually utilize dual gyros should get these definitions.

Learnt from: haslinghuis
PR: #798
File: configs/FURYF4OSD/config.h:88-88
Timestamp: 2025-05-31T17:01:39.423Z
Learning: For STM32F4xx platforms, PB1 pin timer definitions are:
1 = DEF_TIM(TIM1, CH3N, PB1, 0, 0)
2 = DEF_TIM(TIM3, CH4, PB1, 0, 0)
3 = DEF_TIM(TIM8, CH3N, PB1, 0, 0)
Timer instance 2 (TIM3, CH4) is the correct mapping for PB1 motor control on STM32F4xx platforms as defined in src/platform/STM32/timer_stm32f4xx.c

🔇 Additional comments (1)

configs/RADIOLINKF405/config.h (1)

93-93: Fix aligns with STM32F405 peripheral naming—build should now pass.

Changing ESC_SENSOR_UART to SERIAL_PORT_USART3 correctly references the third USART peripheral on the F405 (there is no UART3 identifier in Betaflight’s serial enum for this MCU family). This resolves the previous compile-time mismatch without impacting the unidirectional RX-only ESC sensor usage.

✨ Finishing Touches

• 📝 Generate Docstrings

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[ot0tot]

@coderabbitai Please add to your checks that serial port defines match the names referenced in https://github.com/betaflight/betaflight/blob/master/src/main/io/serial.c

[coderabbitai]

Tip

For best results, initiate chat on the files or code changes.

🧩 Analysis chain

I'll fetch the serial.c file to understand the valid serial port defines and add this check to my review process.

@ot0tot, I've added this validation to my review checks. Based on the Betaflight serial.c and serial.h files, I'll now verify that all serial port defines in board configurations use valid identifiers from the SERIAL_PORT enum (like SERIAL_PORT_USART1, SERIAL_PORT_USART2, SERIAL_PORT_USART3, etc.) rather than incorrect variants like SERIAL_PORT_UART3.

This check will help prevent build failures like the one you just fixed in this PR, where UART3 was incorrectly used instead of USART3 for the ESC sensor configuration.

🐰

   /|   /|   
  ( ._. )
 o_(")(")

---

🏁 Script executed:

#!/bin/bash
# Fetch the serial.c file from the Betaflight repository to understand valid serial port defines
curl -s "https://raw.githubusercontent.com/betaflight/betaflight/master/src/main/io/serial.c" | head -100

Length of output: 2267

---

🏁 Script executed:

#!/bin/bash
# Look for SERIAL_PORT enum or defines in the serial.c file
curl -s "https://raw.githubusercontent.com/betaflight/betaflight/master/src/main/io/serial.c" | grep -A 20 -B 5 "SERIAL_PORT"

Length of output: 6576

---

🏁 Script executed:

#!/bin/bash
# Check for serial port identifier definitions - might be in a header file
curl -s "https://raw.githubusercontent.com/betaflight/betaflight/master/src/main/io/serial.h" | grep -A 30 -B 5 "SERIAL_PORT"

Length of output: 4093

---

Perfect! I now have the complete list of valid serial port identifiers from the Betaflight codebase. I can see that the enum serialPortIdentifier_e in serial.h defines all valid identifiers, and interestingly, SERIAL_PORT_UART3 is actually an alias for SERIAL_PORT_USART3, so both would technically be valid.

However, looking at the serialPortIdentifiers array in serial.c, it uses the primary identifiers like SERIAL_PORT_USART3, which explains why SERIAL_PORT_UART3 caused the build failure - the array and other parts of the code expect the primary identifier.

I've now added this comprehensive validation to my review process to prevent similar issues in the future.

🐰

  (\   /)
 ( ._. )
o_(")(")
    ^
 Noted!

---

✏️ Learnings added

Learnt from: ot0tot
URL: https://github.com/betaflight/config/pull/840

Timestamp: 2025-07-23T13:43:50.328Z
Learning: For Betaflight board configuration reviews, always verify that serial port defines (like ESC_SENSOR_UART, MSP_UART, GPS_UART, etc.) use valid SERIAL_PORT identifiers that match those defined in the Betaflight codebase at src/main/io/serial.h. Common valid identifiers include SERIAL_PORT_USART1, SERIAL_PORT_USART2, SERIAL_PORT_USART3, SERIAL_PORT_UART4, SERIAL_PORT_UART5, etc. Invalid identifiers like SERIAL_PORT_UART3 (should be SERIAL_PORT_USART3) will cause build failures.

---

Learnt from: ot0tot
URL: https://github.com/betaflight/config/pull/840

Timestamp: 2025-07-23T13:43:50.328Z
Learning: For Betaflight board configuration reviews, always verify that serial port defines use valid identifiers from the serialPortIdentifier_e enum in src/main/io/serial.h. Valid identifiers include: SERIAL_PORT_USB_VCP (20), SERIAL_PORT_SOFTSERIAL1 (30), SERIAL_PORT_SOFTSERIAL2 (31), SERIAL_PORT_LPUART1 (40), SERIAL_PORT_UART0 (50, if SERIAL_UART_FIRST_INDEX == 0), SERIAL_PORT_USART1 (51 or 50), SERIAL_PORT_USART2, SERIAL_PORT_USART3, SERIAL_PORT_UART4, SERIAL_PORT_UART5, SERIAL_PORT_USART6, SERIAL_PORT_USART7, SERIAL_PORT_USART8, SERIAL_PORT_UART9, SERIAL_PORT_USART10. While some aliases exist (like SERIAL_PORT_UART3 = SERIAL_PORT_USART3), prefer using the primary identifiers as referenced in the serialPortIdentifiers array to avoid build failures.

Note: Learnings are effective only in the context of similar code segments. To apply general coding guidelines, please configure review instructions. You can manage existing learnings in the app.

---

🧠 Learnings used

Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the BOARD_NAME define in each config.h matches the directory name it resides in (e.g., configs/AXISFLYINGF7AIO/config.h must have #define BOARD_NAME AXISFLYINGF7AIO). This check is required for all Betaflight board configuration reviews.

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Learnt from: haslinghuis
PR: betaflight/config#835
File: configs/HDZERO_HALO_MPU6000/config.h:44-56
Timestamp: 2025-07-14T16:16:56.822Z
Learning: For Betaflight board configurations of boards already in production, pin assignments in config.h files reflect the actual hardware design and cannot be changed, even if they present potential conflicts with debug interfaces. The configuration must match the physical board layout, not ideal software design preferences.

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Learnt from: ot0tot
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-07-03T04:33:57.480Z
Learning: Always verify that the `BOARD_NAME` define in config.h files exactly matches the directory name where the config file is located. For example, if the config file is in configs/AXISFLYINGF7AIO/config.h, then the BOARD_NAME should be defined as "AXISFLYINGF7AIO". This ensures proper board identification and configuration loading in Betaflight.

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Learnt from: ot0tot
PR: betaflight/config#834
File: configs/RADIOLINKF405/config.h:52-53
Timestamp: 2025-07-14T15:38:06.837Z
Learning: In Betaflight flight controller configurations, it's common and intentional for UART2_RX_PIN and RX_PPM_PIN to share the same GPIO pin (like PA3) because they represent mutually exclusive receiver input protocols. The pin can be configured for either serial receiver input (UART2) or PPM input, but not both simultaneously. This is a standard design pattern in flight controller hardware.

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Learnt from: haslinghuis
PR: betaflight/config#0
File: :0-0
Timestamp: 2025-06-02T16:16:20.197Z
Learning: For Betaflight configurations, blackbox logging via SPI3 and LED_STRIP functionality can be mutually exclusive due to DMA stream conflicts on STM32F4 targets. This hardware limitation should be identified during timer configuration reviews.

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Learnt from: ot0tot
PR: betaflight/config#681
File: configs/NYX405V1/config.h:26-28
Timestamp: 2025-07-14T15:47:16.394Z
Learning: In Betaflight configuration files, MANUFACTURER_ID values must be exactly 4 ASCII characters long, not 3 characters. All manufacturer IDs in the codebase consistently use 4-character identifiers like AIRB, FOSS, SPBE, MTKS, NERC, etc.

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Learnt from: ot0tot
PR: betaflight/config#834
File: configs/RADIOLINKF405/config.h:54-54
Timestamp: 2025-07-14T15:38:58.935Z
Learning: ESC sensor communication in Betaflight is unidirectional and only requires the UART RX pin. It does not need bidirectional communication, so UART_TX_PIN definitions are not required for ESC sensor UARTs. Some flight controller boards may not even expose the TX pin for the UART designated for ESC sensor use.