How to Create a Flight Controller Configuration File for Betaflight

Under construction.

This document describes how to create a flight controller configuration file for Betaflight 4.5 and is a work in progress.

Introduction

Firmware 4.5 no longer uses unified-targets but instead uses a configuration file for each flight controller. This guide will walk you through the process of creating a configuration file.

Overview

1. Create a new configuration file in the config repository.
2. The configuration file consists of defines and is independent from using CLI commands. All defines are in the format #define <setting> [value].
3. Other directives can be used in the configuration file, e.g. #ifdef, #else and #endif.

Configuration

License Information

The license information is used to identify the license of the firmware. The configuration file needs to start with:

/*
 * This file is part of Betaflight.
 *
 * Betaflight is free software. You can redistribute this software
 * and/or modify this software under the terms of the GNU General
 * Public License as published by the Free Software Foundation,
 * either version 3 of the License, or (at your option) any later
 * version.
 *
 * Betaflight is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this software.
 *
 * If not, see [http://www.gnu.org/licenses/](http://www.gnu.org/licenses/).
 */

#pragma once

Board Configuration

#define FC_TARGET_MCU ATF435M
#define BOARD_NAME AIRBOTF435
#define MANUFACTURER_ID AIRB

Hardware Defines

For a list of hardware defines please see Definitions for Targets.

Pin Resources

The pin resources are used to configure the pins on the flight controller.

Timer and Dma Resources

The timer and DMA resources are used to configure the timers and DMA on the flight controller. Configure the timer in CLI:

Example using a STM32F722:

#timer
timer A00 AF2
# pin A00: TIM5 CH1 (AF2)
timer A01 AF2
# pin A01: TIM5 CH2 (AF2)
timer A02 AF2
# pin A02: TIM5 CH3 (AF2)
timer A03 AF2
# pin A03: TIM5 CH4 (AF2)
timer B00 AF2
# pin B00: TIM3 CH3 (AF2)
timer B01 AF2
# pin B01: TIM3 CH4 (AF2)
timer C07 AF3
# pin C07: TIM8 CH2 (AF3)
timer C08 AF3
# pin C08: TIM8 CH3 (AF3)
timer C09 AF3
# pin C09: TIM8 CH4 (AF3)

Also set the DMA options, so the command timer map outputs the right values, else they will be -1 for dmaopt (which is unused).

e.g.

dma pin A01 0
# pin A01: DMA1 Stream 4 Channel 6
dma pin A00 0
# pin A00: DMA1 Stream 2 Channel 6

The below is an example of the output after running timer map in CLI:

#timer map

Timer Mapping:
    TIMER_PIN_MAP(0, PA0, 2, 0)
    TIMER_PIN_MAP(1, PA1, 2, 0)
    TIMER_PIN_MAP(2, PA2, 2, -1)
    TIMER_PIN_MAP(3, PA3, 2, -1)
    TIMER_PIN_MAP(4, PB0, 2, 0)
    TIMER_PIN_MAP(5, PB1, 2, 0)
    TIMER_PIN_MAP(6, PC7, 2, -1)
    TIMER_PIN_MAP(7, PC8, 2, -1)
    TIMER_PIN_MAP(8, PC9, 2, -1)

To enable the timer map command you need to add the define USE_TIMER_MAP_PRINT so use either:

make TARGET EXTRA_FLAGS="-DUSE_TIMER_MAP_PRINT"

The TIMER_PIN_MAP config statement is broken down as follows:

TIMER_PIN_MAP(WW, XX, YY, ZZ)

• WW - zero-indexed counter, increment by 1 for each line in the timer map
• XX - pin number to set the timer on
• YY - selected instance of the timer configuration where multiple options are available. See your MCU's target timer code for the list of options. For example F772 should reference this timer file.
• ZZ - DMA setting for that timer, same number as used in the dma pin <pin number> <dma> command.

Serial Configuration

The serial configuration is used to configure the serial ports on the flight controller. The following defines are available:

Value	Function define
1	MSP_UART
2	GPS_UART
64	SERIALRX_UART
32	SBUS_TELEMETRY_UART
1024	ESC_SENSOR_UART
2048	VTX_SMARTAUDIO_UART
8192	VTX_TRAMP_UART
131072	VTX_MSP_UART
131073	MSP_DISPLAYPORT_UART

The following example shows how to configure the serial ports for receiver, GPS and SmartAudio VTX.

#define SERIALRX_UART SERIAL_PORT_USART1
#define VTX_SMARTAUDIO_UART SERIAL_PORT_USART3
#define GPS_UART SERIAL_PORT_USART4

备注

Serial command is zero index based, so the first serial port is SERIAL_PORT_USART1 and not SERIAL_PORT_USART0.

The USART is meant to do all of the “heavy lifting” serial communication during periods of “high” energy consumption.

When the microcontroller is asleep and in a low power mode, though, the UART peripheral can handle low speed communications while offering a reduced energy footprint. Betaflight has UART4, UART5 and UART9. Other serial ports are USUART as some boards provide LPUART1

Gyro Alignment Settings

Gyro alignment configuration is mutual exclusive.

Default we use #define USE_GYRO_1_ALIGN ALIGNMENT

where ALIGNMENT preset is one of

CW0_DEG
CW90_DEG
CW180_DEG
CW270_DEG
CW0_DEG_FLIP
CW90_DEG_FLIP
CW180_DEG_FLIP
CW270_DEG_FLIP
ALIGN_CUSTOM

When using ALIGN_CUSTOM specify orientation in DECIDEGREES ranging from -3600-3600:

#define ALIGN_1_GYRO_ROLL DECIDEGREES
#define ALIGN_1_GYRO_PITCH DECIDEGREES
#define ALIGN_1_GYRO_YAW DECIDEGREES

Serial Receiver Provider

BNF boards may want to configure the serial receiver provider on the flight controller. Example:

#define SERIALRX_PROVIDER CRSF

ADC Configuration

The ADC configuration is used to configure the ADC on the flight controller.

Bus Configuration

The bus configuration is used to configure the I2C and SPI buses on the flight controller.

LED Configuration

The LED configuration is used to configure the LED on the flight controller.

OSD Configuration

The OSD configuration is used to configure the OSD on the flight controller.

VTX Configuration

The VTX configuration is used to configure the VTX on the flight controller.