Table of Contents

Devo F4 Hardware Connections

The following documents the hardware inside the Devo-F4 transmitter

STM32 Connections

NOTE: These are from the Devo-7e. they may need to be updated! '*' Indiciates updated values

Pin Desription
BOOT0 CON2
NRST Debugger (NRESET)

GPIOA

Pin Desription
*0 5.8GHz Receiver channel0 pin
1 Piezo speaker
2 output to 0 to shut off Tx
3 power-switch in 'off' position (goes high on 'off')
*4 5.8GHz signal strength
5 (SPI1_SCK) SPI Flash, LCD
6 (SPI1_MISO) SPI Flash, LCD
7 (SPI1_MOSI) SPI Flash, LCD
*8 5.8GHz Receiver channel1 pin
9 (USART1_TX) Trainer Rx?
10 (USART1_RX) Trainer Tx?
11 (USBDM) USB+
12 (USBDP) USB-
13 (SWDIO) Debugger SWDIO (TMS)
14 (SWCLK) Debugger SWCLK (TCK)
*15 5.8GHz Receiver channel2 pin

GPIOB

Pin Desription
0 LCD Chip Enable
1 LCD Backlight
2 (BOOT1) SPI Flash Chip-Enable
*3 Mix0 Switch
*4 Mix2 Switch
5 Button Matrix Col 1
6 Button Matrix Col 2
7 Button Matrix Col 3
8 Button Matrix Col 4
9 5.8GHz Receiver on/off
10 USB Enable (enable Low)
11 TxModule pin 10 - CYRF6936 Reset
12 (SPI2_NSS?) TxModule pin 1
13 (SPI2_SCK?) TxModule pin 3
14 (SPI2_MISO?) TxModule pin 9
15 (SPI2_MOSI?) TxModule pin 7

GPIOC

Pin Desription
0 (ADC_IN_10) Right Vertical Stick
1 (ADC_IN_11) Left Vertical Stick
2 (ADC_IN_12) Left Horizontal stick
3 (ADC_IN_13) Right Horizontal Stick
4 (ADC_IN_14) Battery Voltage
5 LCD Data/Command mode
6 Button Matrix Row 1
7 Button Matrix Row 2
8 Button Matrix Row 3
9 Button Matrix Row 4
10 FMode2 Switch
11 FMode0 Switch
*12 Hold Switch
13 AIL DR Switch
14 Gear Swicth
*15 TRN Switch

GPIOD

Pin Desription
2 Haptic vibration motor

The battery voltage (ADC1_14) is calculated by the formula:
V = 0.0021x + 0.3026

Button Matrix

B.5 B.6 B.7 B.8
C.6 L- DN- Aileron TL Throttle TD
C.7 R+ UP+ Aileron TR Elevator TD
C.8 Ent Ext Rudder TL Throttle TU
C.9 NC NC Rudder TR Elevator TU

TL: Trim Left TR: Trim Right TU: Trim Up TD: Trim down

FCC Report

FCCID: S29 DEVO-F4

Schematic available here courtesy of user Buoncristiani: schemadevof4v2.pdf

Switch MOD for DEVO F4

see this post