Atmel SAM4S-XPLD Atmel ATSAM4S-XPLD ATSAM4S-XPLD Hoja De Datos

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SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

The SAM-BA

Boot Program integrates an array of programs permitting download and/or upload into the different

memories of the product.



SAM-BA Boot uses the first 2048 bytes of the SRAM for variables and stacks. The remaining available size can be 
used for user's code.



USB Requirements:



 with frequency of:

11,289 MHz

12,000 MHz

16,000 MHz

18,432 MHz



UART0 requirements: None

Note:

1.

Must be 2500 ppm and 1.2V Square Wave Signal.

The SAM-BA Boot program seeks to detect a source clock either from the embedded main oscillator with external crystal
(main oscillator enabled) or from a supported frequency signal applied to the XIN pin (Main oscillator in bypass mode).

If a clock is found from the two possible sources above, the boot program checks to verify that the frequency is one of the
supported external frequencies. If the frequency is one of the supported external frequencies, USB activation is allowed,
else (no clock or frequency other than one of the supported external frequencies), the internal 12 MHz RC oscillator is
used as main clock and USB clock is not allowed due to frequency drift of the 12 MHz RC oscillator.

UART0

URXD0

PA9

UART0

UTXD0

PA10

Device

Setup

Character

received

from UART0

Run SAM-BA Monitor

USB Enumeration

Successful

Yes

Run SAM-BA Monitor

Yes

No

No