Datasheet

11096AS–ATARM–4-Oct-11

SAM9N12

8.3 Peripheral Interrupts and Clock Control

8.3.1 System Interrupt

The System Interrupt in Source 1 is the wired-OR of the interrupt signals coming from:

• the DDR2/LPDDR Controller

• the Debug Unit

• the Periodic Interval Timer

• the Real-Time Clock

• the Watchdog Timer

• the Reset Controller

• the Power Management Controller

The clock of these peripherals cannot be deactivated and Peripheral ID 1 can only be used

within the Advanced Interrupt Controller.

8.3.2 External Interrupts

All external interrupt signals, i.e., the Fast Interrupt signal FIQ or the Interrupt signal IRQ, use a

dedicated Peripheral ID. However, there is no clock control associated with these peripheral IDs.

8.4 Peripheral Signal Multiplexing on I/O Lines

The SAM9N12 features 4 PIO controllers, PIOA, PIOB, PIOC and PIOD, which multiplex the I/O

lines of the peripheral set.

Each PIO Controller controls 32 lines, 19 lines, 32 lines and 22 lines respectively for PIOA, PIOB,

PIOC and PIOD. Each line can be assigned to one of three peripheral functions, A, B or C.

Refer to Section 4. “Package and Pinout” and the package pinout table, Table 4-1, depending on

the package.

8.4.1 Reset State

The column “Reset State” (Table 4-1) indicates the reset state of the line with mnemonics.

• “PIO”/”signal”

Indicates whether the PIO Line resets in I/O mode or in peripheral mode. If “PIO” is mentioned,

the PIO Line is maintained in a static state as soon as the reset is released. As a result, the bit

corresponding to the PIO Line in the register PIO_PSR (Peripheral Status Register) resets low.

If a signal name is mentioned in the “Reset State” column, the PIO Line is assigned to this func-

tion and the corresponding bit in PIO_PSR resets high. This is the case on pins controlling

memories, in particular the address lines, which require the pin to be driven as soon as the reset

is released.

27 Reserved

28 SSC Synchronous Serial Controller

29 Reserved

30 TRNG True Random Number Generator

31 AIC Advanced Interrupt Controller IRQ

Table 8-1. SAM9N12 Peripheral Identifiers (Continued)

Instance ID Instance name Instance description External interrupt Wired-or interrupt