VR4121

PROCESSOR INTERFACE
    - 32-bit LCD interface
    - 16-bit mini-ISA bus interface (as defined by VR4121)
    - DRAM interface and SDRAM controller for
DMA/master mode USB HOST CONTROLLER
    - OpenHCI USB 1.0 compliant
    - Standard communication with USB device; asynchronous communication with host CPU
    - Full-speed (12 Mbps) and low-speed (1.5 Mbps) operation
    - 48-MHz system clock
    - On-chip FIFO
      PCI read: 4 x 4 Dword
      PCI write: 4 x 4 Dword
      USB side: 64 x 1byte
    - Two downstream ports
    - No support for legacy interface
IEEE1284 PARALLEL PORT INTERFACE
    - ECP, EPP, SPP, and P1284 host function with DMA operation
    - Device function operation
SERIAL PORT INTERFACE
    - Two 16550-compatible serial interfaces
PROGRAMMABLE CHIP SELECT AND GENERAL-PURPOSE I/O
    - Six chip selects
    - 24 general-purpose I/O (GPIO) signals
PS/2 INTERFACE
    - PS/2 keyboard and mouse support
PULSE-WIDTH MODULATION (PWM) FOR LCD BACKLIGHT PACKAGE
    - 256-pin TBGA (27 mm square)

The VRC4172^TM companion chip to NEC's VR4121TM MIPS^® RISC microprocessor is designed for high-end Windows® CE Handheld PC Professional applications. The VR4121 microprocessor functions as the host CPU, while the VRC4172 supplies the SDRAM interface, USB interface, host- and peripheral-selectable IEEE-1284 parallel interface, 16550-compliant serial interface, PS/2 interface, general-purpose I/O ports, general-purpose chip select signal, and pulse-width modulation for the LCD back light.

In combination, the VR4121 and VRC4172 offer an excellent performance/cost solution for next-generation Windows CE applications, forming a superior engine for most, if not all, high-performance Windows CE-based handheld products.