
=
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed, distributed or reproduced without permission from Winbond.
4
Versi on 0. 4, March/2000
1. OVERVIEW
The W90221 is a highly integrated 32-bit processor for a wide range of embedded applications, such as set-
top box, web browser and visual/data communication devices. Fig 1-1 shows a block diagram of the overall
system. The W90221 consists of the system support logics as well as an embedded 32-bit PA-RISC
processor.
The 32-bit PA-RISC core has 4K bytes of instruction cache memory, 4K bytes of data cache memory, a
dual-cycle multiply/accumulate module, and integrated functions for interfacing to numerous system
components and external I/O modules. Besides, it’s designed with a flexible power management scheme
(under software control) and lots of low power circuits to eliminate the chip's power consumption. The
W90221 consumes only 375 mA as chip operating at its maximum speed.
The 2-D graphic accelerator is the major mega-functional cell integrated in this chip. This unit provides
directly connect to TV, analog LCD monitor and CRT monitors, intending for low cost web browser solution.
The chip contains an ISA-like bus interface (shared with PCI bus pins) to connect low speed devices, such
as code/data ROM/Flash and traditional ISA-like or IDE devices, an EDO/SDRAM controller compliant with
PC-100 standard, a PCI bridge supporting up to three external PCI masters, a IEEE-1284 compliant parallel
port interface (PPI), two RS-232 type universal asynchronous serial port (UART), two timer channels and a
flexible synchronous interface (SSI) connecting to an external audio or telephony codec devices. The
overall features are listed section 2.
PCI/XIO
Bridge
EDO/SDRAM
Controller
DMA
Controller
Parallel Port
Interface
UART
(x2)
Sync. Serial
Port
Timer (x2)
32-bit Internal DMA bus
32-bit CPU Internal Bus
6-Stage Integer Pipeline
Instr. Cache
RAM
Internal Bus Interface Unit
PLL
Data Cache
RAM
Branch Table
RAM
DPCLK
(27 Mhz)
CPUCLK
PCI/ISA/IDE
ROM/Flash
EDO/SDRAM
Power Mang.
Unit
GFX
Controller
/2
Video-in bus
& TV/Mon
Fig 1-1 : W90221 Internal Block Diagram