Atmel SAM4S Xplained Pro, User Manual

Page: 16 / 21

Atmel SAM4S Xplained Pro [USER GUIDE]
Atmel-42075B-MCU-Atmel SAM4S Xplained Pro-USER GUIDE-03/2013
16
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)