• Advanced Multibus Architecture With Three Separate 16-Bit Data Memory Buses and One Program Memory Bus
• 40-Bit Arithmetic Logic Unit (ALU) Including a 40-Bit Barrel Shifter and Two Independent 40-Bit Accumulators
• 17- × 17-Bit Parallel Multiplier Coupled to a 40-Bit Dedicated Adder for Non-Pipelined Single-Cycle Multiply/Accumulate (MAC) Operation
• Compare, Select, and Store Unit (CSSU) for the Add/Compare Selection of the Viterbi Operator
• Exponent Encoder to Compute an Exponent Value of a 40-Bit Accumulator Value in a Single Cycle
• Two Address Generators With Eight Auxiliary Registers and Two Auxiliary Register Arithmetic Units (ARAUs)
• Data Bus With a Bus Holder Feature
• Address Bus With a Bus Holder Feature (’548 and ’549 Only)
• Extended Addressing Mode for 8M × 16-Bit Maximum Addressable External Program Space (’548 and ’549 Only)
• 192K × 16-Bit Maximum Addressable Memory Space (64K Words Program, 64K Words Data, and 64K Words I/O)
• On-Chip ROM with Some Configurable to Program/Data Memory
• Dual-Access On-Chip RAM
• Single-Access On-Chip RAM (’548/’549)
• Single-Instruction Repeat and Block-Repeat Operations for Program Code
• Block-Memory-Move Instructions for Better Program and Data Management
• Instructions With a 32-Bit Long Word Operand
• Instructions With Two- or Three-Operand Reads
• Arithmetic Instructions With Parallel Store and Parallel Load
• Conditional Store Instructions
• Fast Return From Interrupt
• On-Chip Peripherals
  • Software-Programmable Wait-State Generator and Programmable Bank Switching
  • On-Chip Phase-Locked Loop (PLL) Clock Generator With Internal Oscillator or External Clock Source
  • Full-Duplex Serial Port to Support 8- or 16-Bit Transfers (’541, ’LC545, and ’LC546 Only)
  • Time-Division Multiplexed (TDM) Serial Port (’542, ’543, ’548, and ’549 Only)
  • Buffered Serial Port (BSP) (’542, ’543, ’LC545, ’LC546, ’548, and ’549 Only)
  • 8-Bit Parallel Host-Port Interface (HPI) (’542, ’LC545, ’548, and ’549)
  • One 16-Bit Timer
  • External-Input/Output (XIO) Off Control to Disable the External Data Bus, Address Bus and Control Signals
• Power Consumption Control With IDLE1, IDLE2, and IDLE3 Instructions With Power-Down Modes
• CLKOUT Off Control to Disable CLKOUT
• On-Chip Scan-Based Emulation Logic, IEEE Std 1149.1 (JTAG) Boundary Scan Logic
• 25-ns Single-Cycle Fixed-Point Instruction Execution Time [40 MIPS] for 5-V Power Supply (’C541 and ’C542 Only)
• 20-ns and 25-ns Single-Cycle Fixed-Point Instruction Execution Time (50 MIPS and 40 MIPS) for 3.3-V PowerSupply (’LC54x)
• 15-ns Single-Cycle Fixed-Point Instruction Execution Time (66 MIPS) for 3.3-V Power Supply (’LC54xA, ’548, ’LC549)
• 12.5-ns Single-Cycle Fixed-Point Instruction Execution Time (80 MIPS) for 3.3-V Power Supply (’LC548, ’LC549)
• 10-ns and 8.3-ns Single-Cycle Fixed-Point Instruction Execution Time (100 and 120 MIPS) for 3.3-V Power Supply (2.5-V Core) (’VC549)

IEEE Standard 1149.1-1990 Standard-Test-Access Port and Boundary Scan Architecture.