User manual

Atmel SAM4S Xplained Pro [USER GUIDE]

Atmel-42075B-MCU-Atmel SAM4S Xplained Pro-USER GUIDE-03/2013

Table 4.10. External 12MHz crystals

Pin on SAM4S Function

PB9 XIN0

PB8 XOUT0

4.2.4 Mechanical buttons

SAM4S Xplained Pro contains two mechanical buttons. One button is the RESET button connected to the

SAM4S reset line and the other is a generic user configurable button. When a button is pressed it will drive the

I/O line to GND.

Table 4.11. Mechanical buttons

Pin on SAM4S Silkscreen text

NRST RESET

PC24 SW0

4.2.5 LED

There is one yellow LED available on the SAM4S Xplained Pro board that can be turned on and off. The LED

can be activated by driving the connected I/O line to GND.

Table 4.12. LED connections

Pin on SAM4S LED

PC23 Yellow LED0

4.2.6 Analog reference

An adjustable voltage reference is implemented on the kit to have a reference for the ADC or DAC. The

reference can be adjusted with the on-board multiturn trimmer potentiometer. Next to the potentiometer, a 2-pin

header is available to measure the reference voltage for the AREF pin of the SAM4S. The voltage output range

for the reference is 0V - 3.36V.

4.3 Embedded Debugger implementation

SAM4S Xplained Pro contains an Embedded Debugger (EDBG) that can be used to program and debug the

ATSAM4SD32C using Serial Wire Debug (SWD). The Embedded Debugger also include a Virtual Com port

interface over UART, an Atmel Data Gateway Interface over SPI and TWI and it monitors four of the SAM4S

GPIOs. Atmel Studio can be used as a front end for the Embedded Debugger.

4.3.1 Serial Wire Debug

The Serial Wire Debug (SWD) use two pins to communicate with the target. For further information on how to

use the programming and debugging capabilities of the EDBG, see “Embedded Debugger” on page 6.

Table 4.13. SWD connections

Pin on SAM4S Function

PB7 SWD clock

PB6 SWD data

PB5 SWD trace output

PB12 Erase

4.3.2 Virtual COM port

The Embedded Debugger act as a Virtual Com Port gateway by using one of the ATSAM4SD32C UARTs. For

further information on how to use the Virtual COM port see “Embedded Debugger” on page 6.

Table 4.14. Virtual COM port connections

Pin on SAM4S Function

PB3 UART TXD (SAM4S TX line)