SAM4S Xplained

Overview

The SAM4S Xplained evaluation kit is a development platform to evaluate the Atmel SAM4S series microcontrollers.

SAM4S Xplained

Hardware

  • ATSAM4S16C ARM Cortex-M4 Processor

  • 12 MHz crystal oscillator

  • internal 32.768 kHz crystal oscillator

  • IS66WV51216DALL 8 Mb SRAM

  • Micro-AB USB device

  • Micro-AB USB debug interface supporting SEGGER OB and Virtual COM Port and Data

  • One reset and one user pushbutton

  • 2 yellow user LEDs

  • IC pads for external flash chip

Supported Features

The sam4s_xplained board configuration supports the following hardware features:

Interface

Controller

Driver/Component

NVIC

on-chip

nested vector interrupt controller

SYSTICK

on-chip

systick

UART

on-chip

serial port

USART

on-chip

serial port

I2C

on-chip

i2c

SPI

on-chip

spi

WATCHDOG

on-chip

watchdog

GPIO

on-chip

gpio

HWINFO

on-chip

Unique device serial number

SMC

on-chip

memc (PSRAM)

PWM

on-chip

pwm

ADC

on-chip

adc

Other hardware features are not currently supported by Zephyr.

The default configuration can be found in the Kconfig boards/arm/sam4s_xplained/sam4s_xplained_defconfig.

Connections and IOs

Download the SAM4S Xplained Design Files [2] for more information. It has full schematic and gerbers files.

System Clock

The SAM4S MCU is configured to use the 12 MHz internal oscillator on the board with the on-chip PLL to generate an 84 MHz system clock.

Serial Port

The ATSAM4S16C MCU has 2 UARTs and 2 USARTs. One of the UARTs (UART0) is connected to the Segger J-Link OB chip (the AT91SAM3U4 is programmed to be Segger J-Link OB). Segger J-Link OB brings the UART out as a virtual COM port. The section flashing uses the UART from the Segger USB debug connection.

Programming and Debugging

The SAM4S Xplained board comes with Segger J-Link OB. This provides a debug interface to the SAM4S16C chip. You can use Ozone or JLink to communicate with the SAM4S16C.

Flashing

For flash the board Zephyr provides two paths. One uses the default JLink tool and the second one uses SAM Boot Assistant (SAM-BA).

Using SAM-BA bootloader

  1. Close the J25 jumper on the SAM4S Xplained board. Power on the board for 10s.

  2. Open the J25 jumper.

  3. Connect the SAM4S Xplained board to your host computer using the SoC USB port. Then build and flash the Hello World application.

    # From the root of the zephyr repository
    west build -b sam4s_xplained samples/hello_world
    
    $ west flash -r bossac
    

Visualizing the message

  1. Run your favorite terminal program to listen for output. Under Linux the terminal should be /dev/ttyACM0. For example:

    $ minicom -D /dev/ttyACM0 -o
    

    The -o option tells minicom not to send the modem initialization string. Connection should be configured as follows:

    • Speed: 115200

    • Data: 8 bits

    • Parity: None

    • Stop bits: 1

  2. Press reset button

    You should see “Hello World! sam4s_xplained” in your terminal.

Debugging

You can debug an application in the usual way. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b sam4s_xplained samples/hello_world
west debug

References