11.
Processor and Architecture
11.1. Cortex M0+ Processor
The Atmel SAM L22 implements the ARM ARM
®
Cortex
™
-M0+ processor, based on the ARMv6
Architecture and Thumb
®
-2 ISA. The Cortex M0+ is 100% instruction set compatible with its predecessor,
the Cortex-M0 core, and upward compatible to Cortex-M3 and M4 cores. The implemented ARM Cortex-
M0+ is revision r0p1. For more information refer to
11.1.1. Cortex M0+ Configuration
Table 11-1. Cortex M0+ Configuration
Features
Cortex-M0+ options
SAM L22 configuration
Interrupts
External interrupts 0-32
27
Data endianness
Little-endian or big-endian
Little-endian
SysTick timer
Present or absent
Present
Number of watchpoint comparators
0, 1, 2
2
Number of breakpoint comparators
0, 1, 2, 3, 4
4
Halting debug support
Present or absent
Present
Multiplier
Fast or small
Fast (single cycle)
Single-cycle I/O port
Present or absent
Present
Wake-up interrupt controller
Supported or not supported
Not supported
Vector Table Offset Register
Present or absent
Present
Unprivileged/Privileged support
Present or absent
Present
Memory Protection Unit
Not present or 8-region
8-region
Reset all registers
Present or absent
Absent
Instruction fetch width
16-bit only or mostly 32-bit
32-bit
The ARM Cortex-M0+ core has two bus interfaces:
•
Single 32-bit AMBA-3 AHB-Lite system interface that provides connections to peripherals and all
system memory, which includes flash and RAM.
•
Single 32-bit I/O port bus interfacing to the PORT and DIVAS with 1-cycle loads and stores.
11.1.2. Cortex M0+ Peripherals
•
System Control Space (SCS)
–
The processor provides debug through registers in the SCS. Refer to the Cortex-M0+
Technical Reference Manual for details (
)
•
Nested Vectored Interrupt Controller (NVIC)
–
External interrupt signals connect to the NVIC, and the NVIC prioritizes the interrupts.
Software can set the priority of each interrupt. The NVIC and the Cortex-M0+ processor core
are closely coupled, providing low latency interrupt processing and efficient processing of late
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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