V
R
4 1 2 1 6 4 - B I T M I P S R I S C M I C R O P R O C E S S O R
FOR WINDOWS CE
The 64-bit V
R
4121
TM
(碌PD30121) microprocessor is a member of NEC鈥檚 V
R
Series
TM
devices created
for Windows
廬
CE embedded consumer applications. Designed around the MIPS
廬
RISC architecture
developed by MIPS Technologies, the V
R
4121 offers excellent power consumption and performance in
a highly integrated, low-cost system on a chip.
This microprocessor is the second NEC device to use the ultra-low-power-consuming V
R
4120
TM
CPU
core based on advanced 0.25-micron technology. The V
R
4120 CPU has an optimized five-stage
pipeline, 16-KB instruction cache, 8-KB data cache, multiply-accumulate (MAC) unit, and memory
management unit that enable high performance in a compact, low-cost chip. Integrated peripherals
include a power management unit, direct memory access unit, interrupt control unit, timers, real-time
clock, 16550-compatible serial interface, IrDA
廬
interface, keyboard interface, touch-panel interface,
host signal processing unit (software modem), and A/D and D/A converters.
The V
R
4121 is compatible with MIPS III instruction set architecture (ISA) and MIPS16
application-specific extension (ASE). The MIPS16 ASE compatibility enables the V
R
4121 to
incorporate 16-bit-long instructions with conventional 32-bit-long instructions, resulting in compact
code size, a smaller memory requirement, and lower system cost.
The V
R
4121 provides an easy choice for V
R
4111
TM
customers in terms of upgrade, since the V
R
4121
and V
R
4111 are fully pin compatible. The V
R
4121 microprocessor鈥檚 high speed, compact size, and low
power consumption make it ideal for use in a battery-driven, portable handheld systems.
BLOCK DIAGRAM
Software Modem
Codec
DAA
D/A
Converter
Osc
Osc
Phase
Locked Loop
Host Signal
Processing Unit
Audio
Interface Unit
General-Purpose
I/O Unit
Keyboard
Interface
LED
Interface
Touch-Panel
Interface
Real-Time
Clock
Direct Memory
Access Unit
Deadman's
Switch Unit
Interrupt
Control Unit
Power
Mgmnt Unit
Cache
Memory Unit
LCD
Controller
V
R
4120 CPU
(131, 168 MHz)
16K Instruction Cache
8K Data Cache
PC
Card
Touch
Panel
ROM/
Flash
A/D
Converter
16550
Serial Interface
Fast Infrared
Controller
MIC
SDRAM/
EDO DRAM
Bus Control Unit
V
R
4121
Fast Infrared
Driver
RS232C
Driver
97YL-0256C (10/98)
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