ARM V2M MPS2 Armv7-m (AN385/AN386/AN500)

Overview

The mps2/an385, mps2/an386, and mps2/an500 board targets are three of the mps2 Armv7-m based board targets supported in Zephyr. This document provides details about the support provided for these three Armv7-m mps2 board targets (AN385, AN386, AN500) and the following devices:

  • Nested Vectored Interrupt Controller (NVIC)

  • System Tick System Clock (SYSTICK)

  • Cortex-M System Design Kit UART

ARM V2M MPS2

In addition to enabling actual hardware usage, these board targets can also use FVP to emulate the platforms running on the MPS2+.

More information about the board can be found at the V2M MPS2 Website.

The application note for each of the board can be found as follows:

AN385 is also supported to run with QEMU, and is set to run with QEMU by default.

Note

These board targets makes no claims about its suitability for use with actual MPS2 hardware systems, or any other hardware system.

Hardware

ARM V2M MPS2 provides the following hardware components:

  • ARM Cortex-M Chip

  • ARM IoT Subsystem for Cortex-M

  • Form factor: 140x120cm

  • ZBTSRAM: 8MB single cycle SRAM, 16MB PSRAM

  • Video: QSVGA touch screen panel, 4bit RGB VGA connector

  • Audio: Audio Codec

  • Debug:

    • ARM JTAG20 connector

    • ARM parallel trace connector (MICTOR38)

    • 20 pin Cortex debug connector

    • 10 pin Cortex debug connector

    • ILA connector for FPGA debug

  • Expansion

    • GPIO

    • SPI

Note

4 MB of flash memory (in ZBTSRAM 1, starting at address 0x00400000) and 4 MB of RAM (in ZBTSRAM 2 & 3, starting at address 0x20000000) are available.

Supported Features

The mps2/an385, mps2/an386, and mps2/an500 board targets support the following hardware features:

Interface

Controller

Driver/Component

NVIC

on-chip

nested vector interrupt controller

SYSTICK

on-chip

systick

UART

on-chip

serial port-polling; serial port-interrupt

GPIO

on-chip

gpio

WATCHDOG

on-chip

watchdog

TIMER

on-chip

counter

DUALTIMER

on-chip

counter

Other hardware features are not currently supported by the port. See the V2M MPS2 Website for a complete list of V2M MPS2 board hardware features.

The default configuration can be found in boards/arm/mps2/mps2_an385_defconfig or similarly in mps2_anxxx_defconfig for the other applicable boards.

Interrupt Controller

MPS2 is a Cortex-M based SoC and has 15 fixed exceptions and 45 IRQs.

A Cortex-M3/4/7-based board uses vectored exceptions. This means each exception calls a handler directly from the vector table.

Handlers are provided for exceptions 1-6, 11-12, and 14-15. The table here identifies the handlers used for each exception.

Exc#

Name

Remarks

Used by Zephyr Kernel

1

Reset

system initialization

2

NMI

system fatal error

3

Hard fault

system fatal error

4

MemManage

MPU fault

system fatal error

5

Bus

system fatal error

6

Usage fault

undefined instruction, or switch attempt to ARM mode

system fatal error

11

SVC

system calls, kernel run-time exceptions, and IRQ offloading

12

Debug monitor

system fatal error

14

PendSV

context switch

15

SYSTICK

system clock

Pin Mapping

The ARM V2M MPS2 Board has 4 GPIO controllers. These controllers are responsible for pin muxing, input/output, pull-up, etc.

All GPIO controller pins are exposed via the following sequence of pin numbers:

  • Pins 0 - 15 are for GPIO 0

  • Pins 16 - 31 are for GPIO 1

  • Pins 32 - 47 are for GPIO 2

  • Pins 48 - 51 are for GPIO 3

Mapping from the ARM MPS2 Board pins to GPIO controllers:

  • D0 : EXT_0

  • D1 : EXT_4

  • D2 : EXT_2

  • D3 : EXT_3

  • D4 : EXT_1

  • D5 : EXT_6

  • D6 : EXT_7

  • D7 : EXT_8

  • D8 : EXT_9

  • D9 : EXT_10

  • D10 : EXT_12

  • D11 : EXT_13

  • D12 : EXT_14

  • D13 : EXT_11

  • D14 : EXT_15

  • D15 : EXT_5

  • D16 : EXT_16

  • D17 : EXT_17

  • D18 : EXT_18

  • D19 : EXT_19

  • D20 : EXT_20

  • D21 : EXT_21

  • D22 : EXT_22

  • D23 : EXT_23

  • D24 : EXT_24

  • D25 : EXT_25

  • D26 : EXT_26

  • D27 : EXT_30

  • D28 : EXT_28

  • D29 : EXT_29

  • D30 : EXT_27

  • D31 : EXT_32

  • D32 : EXT_33

  • D33 : EXT_34

  • D34 : EXT_35

  • D35 : EXT_36

  • D36 : EXT_38

  • D37 : EXT_39

  • D38 : EXT_40

  • D39 : EXT_44

  • D40 : EXT_41

  • D41 : EXT_31

  • D42 : EXT_37

  • D43 : EXT_42

  • D44 : EXT_43

  • D45 : EXT_45

  • D46 : EXT_46

  • D47 : EXT_47

  • D48 : EXT_48

  • D49 : EXT_49

  • D50 : EXT_50

  • D51 : EXT_51

Peripheral Mapping:

  • UART_3_RX : D0

  • UART_3_TX : D1

  • SPI_3_CS : D10

  • SPI_3_MOSI : D11

  • SPI_3_MISO : D12

  • SPI_3_SCLK : D13

  • I2C_3_SDA : D14

  • I2C_3_SCL : D15

  • UART_4_RX : D26

  • UART_4_TX : D30

  • SPI_4_CS : D36

  • SPI_4_MOSI : D37

  • SPI_4_MISO : D38

  • SPI_4_SCK : D39

  • I2C_4_SDA : D40

  • I2C_4_SCL : D41

For more details please refer to MPS2 Technical Reference Manual (TRM).

System Clock

The V2M MPS2 main clock is 24 MHz.

Serial Port

The V2M MPS2 processor has five UARTs. Both the UARTs have only two wires for RX/TX and no flow control (CTS/RTS) or FIFO. The Zephyr console output, by default, is utilizing UART0.

Programming and Debugging

Flashing

V2M MPS2 provides:

  • A USB connection to the host computer, which exposes a Mass Storage and an USB Serial Port.

  • A Serial Flash device, which implements the USB flash disk file storage.

  • A physical UART connection which is relayed over interface USB Serial port.

Flashing an application to V2M MPS2

Here is an example for the Hello World application with AN385.

# From the root of the zephyr repository
west build -b mps2/an385 samples/hello_world

Connect the V2M MPS2 to your host computer using the USB port and you should see a USB connection which exposes a Mass Storage and a USB Serial Port. Copy the generated zephyr.bin in the exposed drive. Reset the board and you should be able to see on the corresponding Serial Port the following message:

Hello World! arm

Running an applicatoin with FVP

Here is the same example for running with FVP. Set the ARMFVP_BIN_PATH environemnt variable to the location of your FVP you have downloaded from here

export ARMFVP_BIN_PATH=/home/../FVP_MPS2/

Then build with the same command you would use normally, and run with west build -t run_armfvp.