96Boards Avenger96

Overview

96Boards Avenger96 board is based on ST Microelectronics STM32MP157A multi-core processor, composed of a dual Cortex®-A7 and a single Cortex®-M4 core. Zephyr OS is ported to run on the Cortex®-M4 core.

  • Board features:
    • PMIC: STPMIC1A
    • RAM: 1024 Mbyte @ 533MHz
    • Storage:
      • eMMC: v4.51: 8 Gbyte
      • QSPI: 2Mbyte
      • EEPROM: 128 byte
      • microSD Socket: UHS-1 v3.01
    • Ethernet: 10/100/1000 Mbit/s, IEEE 802.3 Compliant
    • Wireless:
      • WiFi: 5 GHz & 2.4GHz IEEE 802.11a/b/g/n/ac
      • Bluetooth: v4.2 (BR/EDR/BLE)
    • USB:
      • Host - 2x type A, 2.0 high-speed
      • OTG: - 1x type micro-AB, 2.0 high-speed
    • HDMI: WXGA (1366x768)@ 60 fps, HDMI 1.4
    • Connectors:
      • 40-Pin Low Speed Header
      • 60-Pin High Speed Header
    • LEDs:
      • 4x Green user LEDs
      • 1x Blue Bluetooth LED
      • 1x Yellow WiFi LED
      • 1x Red power supply LED
96Boards Avenger96

More information about the board can be found at the 96Boards website.

Hardware

The STM32MP157A SoC provides the following hardware capabilities:

  • Core:
    • 32-bit dual-core Arm® Cortex®-A7
      • L1 32-Kbyte I / 32-Kbyte D for each core
      • 256-Kbyte unified level 2 cache
      • Arm® NEON™
    • 32-bit Arm® Cortex®-M4 with FPU/MPU
      • Up to 209 MHz (Up to 703 CoreMark®)
  • Memories:
    • External DDR memory up to 1 Gbyte.
    • 708 Kbytes of internal SRAM: 256 KB of AXI SYSRAM + 384 KB of AHB SRAM + 64 KB of AHB SRAM in backup domain.
    • Dual mode Quad-SPI memory interface
    • Flexible external memory controller with up to 16-bit data bus
  • Clock management:
    • Internal oscillators: 64 MHz HSI oscillator, 4 MHz CSI oscillator, 32 kHz LSI oscillator
    • External oscillators: 8-48 MHz HSE oscillator, 32.768 kHz LSE oscillator
    • 6 × PLLs with fractional mode
  • General-purpose input/outputs:
    • Up to 176 I/O ports with interrupt capability
  • Interconnect matrix
  • 3 DMA controllers
  • Communication peripherals:
    • 6 × I2C FM+ (1 Mbit/s, SMBus/PMBus)
    • 4 × UART + 4 × USART (12.5 Mbit/s, ISO7816 interface, LIN, IrDA, SPI slave)
    • 6 × SPI (50 Mbit/s, including 3 with full duplex I2S audio class accuracy)
    • 4 × SAI (stereo audio: I2S, PDM, SPDIF Tx)
    • SPDIF Rx with 4 inputs
    • HDMI-CEC interface
    • MDIO Slave interface
    • 3 × SDMMC up to 8-bit (SD / e•MMC™ / SDIO)
    • 2 × CAN controllers supporting CAN FD protocol, TTCAN capiblity
    • 2 × USB 2.0 high-speed Host+ 1 × USB 2.0 full-speed OTG simultaneously
    • 10/100M or Gigabit Ethernet GMAC (IEEE 1588v2 hardware, MII/RMII/GMII/RGMI)
    • 8- to 14-bit camera interface up to 140 Mbyte/s
    • 6 analog peripherals
    • 2 × ADCs with 16-bit max. resolution.
    • 1 × temperature sensor
    • 2 × 12-bit D/A converters (1 MHz)
    • 1 × digital filters for sigma delta modulator (DFSDM) with 8 channels/6 filters
    • Internal or external ADC/DAC reference VREF+
  • Graphics:
    • 3D GPU: Vivante® - OpenGL® ES 2.0
    • LCD-TFT controller, up to 24-bit // RGB888, up to WXGA (1366 × 768) @60 fps
    • MIPI® DSI 2 data lanes up to 1 GHz each
  • Timers:
    • 2 × 32-bit timers with up to 4 IC/OC/PWM or pulse counter and quadrature (incremental) encoder input
    • 2 × 16-bit advanced motor control timers
    • 10 × 16-bit general-purpose timers (including 2 basic timers without PWM)
    • 5 × 16-bit low-power timers
    • RTC with sub-second accuracy and hardware calendar
    • 2 × 4 Cortex®-A7 system timers (secure, non-secure, virtual, hypervisor)
    • 1 × SysTick Cortex®-M4 timer
  • Hardware acceleration:
    • HASH (MD5, SHA-1, SHA224, SHA256), HMAC
    • 2 × true random number generator (3 oscillators each)
    • 2 × CRC calculation unit
  • Debug mode:
    • Arm® CoreSight™ trace and debug: SWD and JTAG interfaces
    • 8-Kbyte embedded trace buffer
    • 3072-bit fuses including 96-bit unique ID, up to 1184-bit available for user

More information about STM32P157A can be found here:

Supported Features

The Zephyr 96b_avenger96 board configuration supports the following hardware features:

Interface Controller Driver/Component
NVIC on-chip nested vector interrupt controller
GPIO on-chip gpio
UART on-chip serial port-polling; serial port-interrupt
PINMUX on-chip pinmux

The default configuration can be found in the defconfig file: boards/arm/96b_avenger96/96b_avenger96_defconfig

Connections and IOs

96Boards Avenger96 Board schematic is available here: Avenger96 board schematics.

Default Zephyr Peripheral Mapping:

  • UART_7 TX/RX/RTS/CTS : PE8/PE7/PE9/PE10 (UART console)
  • UART_4 TX/RX : PD1/PB2

System Clock

The Cortex®-M4 Core is configured to run at a 209 MHz clock speed.

Serial Port

96Boards Avenger96 board has 3 U(S)ARTs. The Zephyr console output is assigned by default to the RAM console to be dumped by the Linux Remoteproc Framework on Cortex®-A7 core. Alternatively, Zephyr console output can be assigned to UART7 which is disabled by default. UART console can be enabled through board’s device tree and 96b_avenger96_defconfig board file (or prj.conf project files), and will disable existing RAM console output. Default UART console settings are 115200 8N1.

Programming and Debugging

The STM32MP157A doesn’t have QSPI flash for the Cortex®-M4 and it needs to be started by the Cortex®-A7 core. The Cortex®-A7 core is responsible to load the Cortex®-M4 binary application into the RAM, and get the Cortex®-M4 out of reset. The Cortex®-A7 can perform these steps at bootloader level or after the Linux system has booted.

The Cortex®-M4 can use up to 2 different RAMs. The program pointer starts at address 0x00000000 (RETRAM), the vector table should be loaded at this address These are the memory mappings for Cortex®-A7 and Cortex®-M4:

Region Cortex®-A7 Cortex®-M4 Size
RETRAM 0x38000000-0x3800FFFF 0x00000000-0x0000FFFF 64KB
MCUSRAM 0x10000000-0x1005FFFF 0x10000000-0x1005FFFF 384KB
DDR 0xC0000000-0xFFFFFFFF   up to 1 GB

Refer to stm32mp157 boot Cortex-M4 firmware wiki page for instruction to load and start the Cortex-M4 firmware.

Debugging

You can debug an application using OpenOCD and GDB. The Solution proposed below is based on the Linux STM32MP1 SDK OpenOCD and is available only for a Linux environment. The firmware must first be loaded by the Cortex®-A7. Developer then attachs the debugger to the running Zephyr using OpenOCD.

Prerequisite

install stm32mp1 developer package.

  1. start OpenOCD in a dedicated terminal

    • Start up the sdk environment:

      source <SDK installation directory>/environment-setup-cortexa7hf-neon-vfpv4-openstlinux_weston-linux-gnueabi
      
    • Start OpenOCD:

      ${OECORE_NATIVE_SYSROOT}/usr/bin/openocd -s ${OECORE_NATIVE_SYSROOT}/usr/share/openocd/scripts -f board/stm32mp15x_ev1_jlink_jtag.cfg
      
  2. run gdb in Zephyr environment

    # On Linux
    cd $ZEPHYR_BASE/samples/hello_world
    mkdir -p build && cd build
    
    # Use cmake to configure a Ninja-based build system:
    cmake -GNinja -DBOARD=96b_avenger96 ..
    
    # Now run ninja on the generated build system:
    ninja debug