This page is for the STM32F4 Discovery board with STM32F407VGT6, STM32F4 Disco is a familiar board with STM32F401VCT6, do not use this Files for the Disco board !

Overview

STMicroelectronics STM32F4VGT6 Cortex M4 MCU, up to 168Mhz with floating point unit (FPU), 192 KB RAM, 1024 KB Flash
on-board STLinkv2 with SWD header (capable of programming onboard or external MCU)
on-board power regulator for the MCU (3V or 5V Input)
1 x user push button
4(5) x LED (orange, green, red, blue, green)
4(6) x UART (UART1, UART2, UART3, (UART4, UART5), UART6)
1(3) x SPI (SPI1, (SPI2, SPI3))
2(3) x I2C (I2C1, I2C2, (I2C3))
6 x ADC inputs (one is used for BAT voltage)
1 x PPM input
1 x Spektrum input (with bind pin)
97 x 66 mm PCB
4 x status LED (USB red, USB green, power, USB OTG green, USB OTG red)
LIS302DL MEMS 3 axis accelerometer on SPI1

Pinout

The Discovery has a male 100 pin (2x25pin on both sides, also accessible on both sides of the pcb) pinout.

**LED**
Pin #	Name	Type	Description	Color
PD13	LED_3	Out	above LIS302DL	Orange
PD12	LED_4	Out	left of LIS302DL	Green
PD14	LED_5	Out	right of LIS302DL	Red
PD15	LED_6	Out	below LIS302DL	Blue
PA9	LED_9	Out	same as USB power (VBUS, needs to be enabled in header file)	Green

**UART1**
Pin #	Name	Type	Description
PB6	UART1 TX	Out	UART1 Serial Output, 4k7 pullup for I2C
PB7	UART1 RX	In	UART1 Serial Input

**UART2**
Pin #	Name	Type	Description
PD5	UART2 TX	Out	UART2 Serial Output (usb otg power management fault output open drain)
PD6	UART2 RX	In	UART2 Serial Input, also used for Spektrum input

**UART3**
Pin #	Name	Type	Description
PD8	UART3 TX	Out	UART3 Serial Output
PD9	UART3 RX	In	UART3 Serial Input

**UART4 (Can NOT be used if SPI_3 is active!)**
Pin #	Name	Type	Description
PC10	UART4 TX	Out	UART4 Serial Output
PC11	UART4 RX	In	UART4 Serial Input

**UART5 (Can NOT be used if SPI_3 is active!)**
Pin #	Name	Type	Description
PC12	UART5 TX	Out	UART5 Serial Output
PD2	UART5 RX	In	UART5 Serial Input

**UART6**
Pin #	Name	Type	Description
PC6	UART6 TX	Out	UART6 Serial Output
PC7	UART6 RX	In	UART6 Serial Input

**SPI1 (for onboard LIS302DL)**
Pin #	Name	Type	Description
PA5	SPI1 SCK	I/O	SPI1 Serial clock
PA6	SPI1 MISO	I/O	SPI1 Master In Slave Out
PA7	SPI1 MOSI	I/O	SPI1 Master Out Slave In
PE3	SPI SS2	I/O	SPI1 Select Slave2

**SPI1**
Pin #	Name	Type	Description
PB3	SPI1 SCK	I/O	SPI1 Serial clock
PB4	SPI1 MISO	I/O	SPI1 Master In Slave Out
PB5	SPI1 MOSI	I/O	SPI1 Master Out Slave In
PE2	SPI SS0	I/O	SPI1 Select Slave0

**SPI2 (Can NOT be used if PWM10 & PWM11 is active!)**
Pin #	Name	Type	Description
PB13	SPI2 SCK	I/O	SPI2 Serial clock
PB14	SPI2 MISO	I/O	SPI2 Master In Slave Out
PB15	SPI2 MOSI	I/O	SPI2 Master Out Slave In
PE7	SPI SS1	I/O	SPI2 Select Slave1

**SPI3 (Can NOT be used if UART4 & UART5 is active!)**
Pin #	Name	Type	Description
PC10	SPI3 SCK	I/O	SPI3 Serial clock
PC11	SPI3 MISO	I/O	SPI3 Master In Slave Out
PC12	SPI3 MOSI	I/O	SPI3 Master Out Slave In
PE3	SPI SS2	I/O	SPI3 Select Slave2 (also used for LIS302DL (SPI1) Slave Select)

**I2C1**
Pin #	Name	Type	Description
PB8	I2C1 SCL	I/O	I2C1 Serial Clock
PB9	I2C1 SDA	I/O	I2C1 Serial Data

**I2C2**
Pin #	Name	Type	Description
PB10	I2C2 SCL	I/O	I2C2 Serial Clock (also used for MP45DT02 MEMS MIC clock in)
PB11	I2C2 SDA	I/O	I2C2 Serial Data

**I2C3 (Can NOT be used if Spektrum bind / PPM input is active!)**
Pin #	Name	Type	Description
PA8	I2C3 SCL	I/O	I2C3 Serial Clock
PC9	I2C3 SDA	I/O	I2C3 Serial Data

Note: is disabled in header file, PA8 is used as Spektrum bind pin, PC9 is used as PPM (not Spektrum) input

**ADC**
Pin #	Name	Type	Description
PB1	AUX1	I/O	ADC_1
PC5	AUX2	I/O	ADC_2
PC4	AUX3	I/O	ADC_3
PA4	AUX4/BAT	I/O	ADC_4, is used for BAT voltage
PC1	AUX5	I/O	ADC_5
PC2	AUX6	I/O	ADC_6

**PWM**
Pin #	Name	Type	Description
PE9	PWM0	Out	Servo 1
PE11	PWM1	Out	Servo 2
PE13	PWM2	Out	Servo 3
PE14	PWM3	Out	Servo 4
PE5	PWM4	Out	Servo 5
PE6	PWM5	Out	Servo 6
PA3	PWM6	Out	Servo 7
PA2	PWM7	Out	Servo 8
PA1	PWM8	Out	Servo 9
PA0	PWM9	Out	Servo 10
PB14	PWM10	Out	Servo 11, Can not be used if SPI2 is active
PB15	PWM11	Out	Servo 12, Can not be used if SPI2 is active

**PPM**
Pin #	Name	Type	Description
PC9	PPM	In	PPM input (remember, you need 100 Ohm serial termination in order to use this)

**Spektrum**
Pin #	Name	Type	Description
PA8	Bind	Out	Spektrum bind pin
PA10	PPM	IN	Spektrum PPM in

Jumper

**Jumper**
Pin #	Name	Type	Description
JP1	JP1	Switch	MCU Current can be measured here
CN3	CN3	Switch	closed: STLinkV2 is connected to onboard MCU, open: is not connectec to onboard, only external header

**Soolder Jumper**
Pin #	Name	Type	Description
SB17	SB17	Switch	Bypass for JP1, close this for security ! (if JP1 gets loose there is no power supply for the mcu)

Daughterboard

Currently we have two different breakout/baughter boards.

SMD & Molex

Another option with Molex connectors, levelshifters for I2C and SPI, as well as connectors for Spektrum satellites and a can phy would be:

Currently under testing, eagle files are coming, when its completely finished and airworthy :-)

THT

Target for this board is to be a ultra low cost THT daughterboard which should provide as many functions as possible. Also it should be as simple as possible (hence no SMD Components were used).

Notes

Tall screw terminals can touch the THT solder joints from the discovery board. No electrical but a mechanical contact can appear. Don't force both pcb's all the way together (leave a small gap).
Only mount the components needed.
If IR_Sensors are used used, maybe the diodes shouldn't be mounted and the voltage divider should be changed.
If you use the 22k/2.2k voltage divider for the BAT input, you need to change the VoltageOfAdc see Airframe_Configuration#Battery.

Servo Power options

External power source (to power servos with a higher voltage or an other voltage regulator, only GND stays connected).
Power servos from the 5V rail, solder the two solder bridges near the three row header.

The servo rail also powers the RC receiver directly (PPM and Spektrum), take care of that if this rail runs on a higher voltage than 5V!
Servo and 5V net share the same GND!

IMU mounting options

Drotek 10 DOF can be soldered on the appropriate footprint. (phi, theta and psi need to be 180 degree offset)
Other IMUs (e.g. MPU6050 breakout) can be soldered on the prototyling area. Use wires to connect it to the Droteks I2C2 pins e.g..
Mount IMU elsewhere and connect it with cables.

BAT voltage

If you use the 22k/2.2k Resistor divider, you will need to redefine the values for the ADC conversation.

File: conf/airframes/myplane.xml

  <section name="BAT">
    ...
    <define name="VOLTAGE_ADC_SCALE" value="0.008864469"/> <!-- R1 (Bat - ADC input) = 22k, R2 (ADC input - GND) = 2.2K--->
    <define name="VOLTAGE_OFFSET" value="0" unit="V"/>
    <define name="VoltageOfAdc(adc)" value="(VOLTAGE_ADC_SCALE * adc + VOLTAGE_OFFSET)"/>
  </section>

Also see Airframe_Configuration#Battery.

Firmware Flashing

FLASH_MODE=STLINK is set as default

STM32F4 Discovery can mainly be programmed in two different ways:

STLINK

with onboard STLinkV2 over SWD
required hardware: usb to mini USB cable
required software: st_flash and st_util from Texane
more information: STLink page

DFU-UTIL

with the MCU native (embedded in rom) DFU USB bootloader over the micro USB AB connector
required hardware: USB to micro and USB to mini usb cable
required external software: dfu-util
push MCU in DFU mode: connect mini(for power) and micro USB to PC, connect pin BOOT0 with 3V, press reset button(LED LD7 should light up now), disconnect BOOT0
more information: DFU page

Supplier

THe STM discovery boards look all quite alike. To make sure you get the right board here a direct [link at Farnell] Whatever supplier yo choose make sure it is a STM32F407 ,mind the 07 in the end, board.

STM32F4 Discovery

Contents

Overview