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Cortex-A characteristics

All Cortex-A based processors share a commonly supported architecture and feature set. ARMv7-A processors support a 32-bit instruction set and data path as well as the mixed 16/32-bit Thumb2 instruction set. ARMv8-A Cortex-A processors add support for a 64-bit data path and the AArch64 execution state while retaining full backward compatibility with ARMv7-A in the AArch32 execution state. This backwards compatibility strengthens the ARM ecosystem and preserves more than a decade worth of ecosystem development.

Cortex-A processors offer support for a range of full Operating Systems including Linux, as well as others requiring a Memory Management Unit such as Android, Chrome and MontaVista.

Cortex-A series processors have been developed to run a number of architecture extensions:

• ARM TrustZone®, to provide support for security 
• SIMD and Advanced SIMD (NEON) technologies 
• ARM Floating Point architecture (VFP)
• big.LITTLE technology
• Large Physical Address Extension (LPAE) addressing up to 1TB of physical memory on some of the 32-bit ARMv7-A processors.

Multicore technology

All ARMv7-A and ARMv8-A based processor cores featured in the current ARM Processor Portfolio support ARM's multicore cache memory architecture:

• Single to quad-core configurations with full hardware coherence 
• Supports symmetric and asymmetric OS implementations 
• Coherency with external non-cached bus masters via the Accelerator Coherency Port (ACP) 
• Coherency with other CPU clusters through AMBA® 4 ACE (AMBA Coherency Extension) and AMBA 5 CHI (Coherent Hub Interface). This enables big.LITTLE designs as well as large core count systems for network infrastructure and the data center.