Usb; Crystals; Mechanical Buttons - Atmel SAM4E Xplained Pro User Manual

Table 4-10 CAN Connections
SAM4E pin
PC12
PC15
4.2.6.

USB

The SAM4E Xplained Pro has a Micro-USB receptable for use with the SAM4E USB device module
labeled "target usb" on the board. To be able to detect when a USB cable is connected, a GPIO (PE2) is
used to detect the VBUS voltage on the connector.
Table 4-11 USB Connections
Table 4-11 USB Connections
SAM4E pin
PE2
PB10
PB11
4.2.7.

Crystals

The SAM4E Xplained Pro kit contains two crystals that can be used as clock sources for the SAM4E
device. Each crystal has a cut-strap next to it that can be used to measure the oscillator safety factor.
This is done by cutting the strap and adding a resistor across the strap. More information about oscillator
allowance and safety factor can be found in the Atmel application note
32kHz crystal oscillators for Atmel AVR
Table 4-12 External 32.768kHz Crystal
Pin on SAM4E
PA7
PA8
Table 4-13 External 12MHz Crystal
Pin on SAM4E
PB9
PB8
Important: Load capacitor calculation, selection and verification was done wrong in the design
of the SAM4E Xplained Pro evaluation kit, see the errata section for more information.
Related Links
12MHz Crystal Selection
4.2.8.

Mechanical Buttons

SAM4E Xplained Pro contains two mechanical buttons. One button is the RESET button connected to the
SAM4E reset line and the other is a generic user configurable button. When a button is pressed it will
Function CAN function
CANRX1 CAN RX
CANTX1 CAN TX
on page 22 lists all I/O-lines connected to the USB connector.
Function USB function
GPIO VBUS detection
DFSD_N USB D-
DFSD_P USB D+
microcontrollers.
on page 26
Shared functionality
Shared functionality
EXT2 GPIO
AVR4100: Selecting and testing
Function
XIN32
XOUT32
Function
XIN
XOUT
Atmel SAM4E Xplained Pro [USER GUIDE]
Atmel-42216B-SAM4E-Xplained-Pro_User Guide-09/2015
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