Read Address Channel (AR)

Complete technical reference for AXI4 Read Address Channel - master all AR signals, handshaking protocols, burst address generation, and implementation details for high-performance SoC design.

ARADDR Signal Design

Address bus width configuration, byte addressing, word alignment, and address space mapping.

ARLEN Burst Length

Burst length encoding (0-255), transfer count calculation, and burst size limitations.

ARSIZE Transfer Size

Size encoding (1, 2, 4, 8, 16, 32, 64, 128 bytes), narrow transfers, and data bus utilization.

ARBURST Burst Type

FIXED (0x00), INCR (0x01), WRAP (0x10) burst types, address calculation, and boundary conditions.

ARLOCK Lock Type

Normal (0b0), Exclusive (0b1) access types, atomic operations, and locking mechanisms.

ARCACHE Cache Attributes

Cacheable, Bufferable, Read-Allocate, Write-Allocate encoding (AxCACHE[3:0]) and memory types.

ARPROT Protection Type

Privileged/Unprivileged, Secure/Non-Secure, Instruction/Data access encoding (ARPROT[2:0]).

ARQOS Quality of Service

QoS identifier (ARQOS[3:0]), traffic prioritization, bandwidth allocation, and arbitration weight.

ARREGION Region Identifier

Memory region encoding (ARREGION[3:0]), address space partitioning, and routing decisions.

ARID Transaction ID

Transaction identification, ID width configuration, out-of-order completion tracking, and correlation.

ARUSER User Signals

User-defined sideband signals, custom attributes, vendor extensions, and metadata transport.

ARVALID/ARREADY Handshake

Handshaking protocol, valid assertion rules, ready deassertion, and timing relationships.

Address Channel Timing

Setup/hold requirements, clock-to-output delays, propagation timing, and critical paths.

Address Alignment Rules

Natural alignment requirements, unaligned access handling, and address calculation algorithms.

Burst Address Generation

Address incrementing logic, wrap boundary calculation, and fixed address handling.

Address Channel FSM

State machine design, idle/active states, backpressure handling, and flow control logic.

Outstanding Read Tracking

Multiple outstanding reads, ID management, reordering buffers, and completion tracking.

Address Decoding Logic

Address range checking, slave selection, decode logic optimization, and routing decisions.

Protection Checking

Address range protection, privilege validation, security attribute checking, and access control.

Address Channel Buffering

FIFO depth calculation, buffer sizing, flow control, and backpressure propagation.

Address Channel Verification

Protocol checkers, assertion properties, coverage models, and validation methodology.

Master-Side Implementation

Read request generation, address calculation, burst management, and flow control logic.

Interconnect Integration

Address routing, arbitration logic, crossbar connectivity, and multi-master support.

Performance Optimization

Address channel utilization, burst optimization, latency reduction, and bandwidth maximization.