STM32F746G-DISCO

User Manual

Introduction

The STM32F746G-DISCO discovery board (32F746GDISCOVERY) is a complete demonstration and development platform for STMicroelectronics ARM® Cortex®-M7 corebased STM32F746NGH6 microcontroller. This microcontroller features four I2Cs, six SPIs with three multiplexed simplex I2S, SDMMC, four USARTs, four UARTs, two CANs, three 12-bit ADCs, two 12-bit DACs, two SAIs, 8- to 14-bit digital camera module interface, internal 320+16+4-Kbyte SRAM and 1-Mbyte Flash memory, USB HS OTG, USB FS OTG, Ethernet MAC, FMC interface, Quad-SPI interface, SWD debugging support. This discovery board offers everything required for users to get started quickly and develop applications easily.

The full range of hardware features on the board helps users to evaluate almost all peripherals (USB OTG HS, USB OTG FS, 10/100-Mbit Ethernet, microSD card, USART, SAI Audio DAC stereo with audio jack input and output, MEMS digital microphones, SDRAM, Quad-SPI Flash memory, 4.3-inch color LCD-TFT with a capacitive multi-touch panel, SPDIF RCA input, etc.) and to develop their applications. Arduino Uno V3 connectors make it possible to easily connect extension shields or a daughterboard for users’ specific applications. The integrated ST-LINK/V2-1 provides an embedded in-circuit debugger and programmer for the STM32.

The STM32F746G-DISCO board comes with the STM32 comprehensive software HAL library together with various packaged software examples, as well as a direct access to ARM® mbed online resources at http://mbed.org.

 

Features

Supported by a wide choice of integrated development environments

 

Embedded ST-LINK/V2-1

The ST-LINK/V2-1 programming and debugging tool is integrated on the  

STM32F746G-DISCO discovery board. Compared to ST-LINK/V2 the changes are listed below.

The new features supported on ST-LINK/V2-1 are:

For all general information concerning debugging and programming features common between V2 and V2-1 refer to ST-LINK/V2 in-circuit debugger/programmer for STM8 and STM32 User manual (UM1075).

 

Power supply

The STM32F746G-DISCO discovery board is designed to be powered by 5V DC power supply. It is possible to configure the discovery board to use any of the following five sources for the power supply:

Programming/debugging when the power supply is not from

ST-LINK (5V link)

It is mandatory to power the board first using JP1 (5V ext) or (usb_hs) or (usb_fs), then connecting the USB cable to the PC. Proceeding this way ensures that the enumeration succeeds thanks to the external power source.

The following power sequence procedure must be respected:

  1. Connect the jumper JP1 on (5V ext) or (usb_hs) or (usb_fs)
  2. Connect the external power source to JP2 or CN6 or CN12 or CN13
  3. Check the red LED LD2 is turned ON
  4. Connect the PC to USB connector CN14

     

    If this order is not respected, the board may be powered by VBUS first from ST-LINK, and the following risks may be encountered:

  1. If more than 500 mA current is needed by the board, the PC may be damaged or current can be limited by the PC. As a consequence the board is not powered correctly.
  2. 500 mA will be requested at the enumeration, so there is a risk that the request is rejected and enumeration does not succeed if the PC cannot provide such current.

Clock sources

Up to 3 clock sources as described below:

Reset sources

The reset signal of STM32F746G-DISCO discovery board is active low and the reset sources include:

Audio

An audio codec WM8994ECS/R from CIRRUS with 4 DACs and 2ADCs is connected to SAI interface of STM32F746NGH6. It communicates with STM32F746NGH6 via I2C bus shared with the camera module and I2C extension connector.

USB OTG FS

The STM32F746G-DISCO discovery board supports USB OTG full speed communication via a USB micro-AB connector (CN13) and USB power switch (U6) connected to VBUS. The discovery board can be powered by this USB connection at 5V DC with 500mA current limitation.

A green LED LD5 will be lit in one of these cases:

USB OTG HS

The STM32F746G-DISCO discovery board supports the USB OTG high speed communication via a USB micro-AB connector (CN12), USB high speed PHY (U15) USB3320C-EZK from MICROCHIP for high speed function.

The discovery board can be powered by the USB connectors (CN12) at 5V DC with 500mA current limitation.

A USB power switch (U7) is also connected on VBUS and provides power to CN12.

The green LED LD4 will be lit in one of these cases:

•   Power switch (U17) is ON and STM32F746G-DISCO works as an USB host  •   VBUS is powered by another USB host when STM32F746G-DISCO works as an USB device.

The red LED LD3 will be lit when an overcurrent occurs.

Note:           STM32F746G-DISCO board should be powered by an external power supply when using OTG function.

microSD card

The 2-Gbyte (or more) microSD card connected to the SDMMC1 port of the STM32F746NGH6 is supported by the board.

Ethernet

The STM32F746G-DISCO discovery board supports 10/100-Mbit Ethernet communication by a PHY LAN8742A-CZ-TR (U9) from MICROCHIP and RJ45 jack (CN9). Ethernet PHY is connected to STM32F746NGH6 via RMII interface.

25 MHz clock for the PHY is generated by the oscillator X2, the 50 MHz clock for the STM32F746NGH6 is generated by the PHY RMII_REF_CLK.

SDRAM memory

128-Mbit SDRAM (MT48LC4M32B2B5-6A from MICRON) is connected to the FMC interface of the STM32F746NGH6. Only the lowest 16-bit data are used (64-Mbit accessible). DQ16 to DQ31 are unused and connected to a 10K ohm pull-down resistor.

Quad-SPI Nor Flash memory

128-Mbit Quad-SPI Nor Flash memory (N25Q128A13EF840E from MICRON) is connected to the Quad-SPI interface of the STM32F746NGH6.

Camera module

A connector P1 with the DCMI signals is available to connect a camera module such as STM32F4DIS-CAM (ST order code).

Display LCD-TFT

The color display from ROCKTECH, 4.3-inch 480x272 LCD-TFT with capacitive touch panel is connected to RGB LCD interface of the STM32F746NGH6.