DESCRIPTION
The µPD30121 (VR4121) is one of NEC’s VR SeriesTM RISC (Reduced Instruction Set Computer) microprocessors and is a high-performance 64-/32-bit microprocessor employing the MIPSTM RISC architecture.
The VR4121 uses the high-performance, super power-saving VR4120TM as the CPU core, and has many peripheral functions such as a DMA controller, software modem interface, serial interface, keyboard interface, IrDA interface, touch panel interface, real-time clock, A/D converter, and D/A converter. Configured with these functions, the VR4121 is suitable for high-speed battery-driven portable information systems. The external memory bus width can be selected from 32 bits and 16 bits, realizing high-speed data transfer.

FEATURES
• Employs 64-bit MIPS architecture
   • Conforms to MIPS III instruction set (deleting FPU, LL, LLD, SC, and SCD instructions)
   • Optimized 6-stage pipeline
• Supports MIPS16 instruction set
• Supports high-speed product-sum operation instructions
• Supports four types of operating modes, enabling more effective power-consumption management
• Internal maximum operating frequency: 131/168 MHz
• On-chip clock generator
• Address space physical: 32 bits
                           virtual: 40 bits
  Integrates 32 double entry TLBs
• High-capacity instruction/data separated cache memories
   Instruction: 16 Kbytes
   Data: 8 Kbytes
• Memory controller (ROM, EDO-type DRAM, synchronous DRAM (SDRAM), synchronous ROM (SROM), and flash memory supported)
• Keyboard interface and touch panel interface
• 4-channel DMA controller
• Serial interface (NS16550 compatible)
• IrDA interface for infrared communication
• Software modem interface
• A/D and D/A converters to support digital voice I/O
• Supports ISA bus subset
• Power supply voltage: VDD2 = 2.5 V (internal), VDD3 = 3.3 V (external) (131 MHz model)
• Package: 224-pin fine-pitch FBGA

APPLICATIONS
• Battery-driven portable information systems
• Embedded controllers, etc.