Protocols
AMBA (Advanced Microcontroller Bus Architecture)
ARM's open standard for on-chip interconnect specification, including APB, AHB, and AXI protocols.
Detailed Explanation
AMBA defines a family of bus protocols for connecting functional blocks in a System-on-Chip (SoC). The protocols are hierarchical: AXI (Advanced eXtensible Interface) handles high-performance connections between processors and memory; AHB (Advanced High-performance Bus) serves mid-tier peripherals; APB (Advanced Peripheral Bus) connects low-bandwidth peripherals.
Each protocol balances complexity against performance. APB is simple with two-phase transactions. AXI supports out-of-order completion, multiple outstanding transactions, and separate read/write channels for maximum throughput.