The Design And Implementation Of An All-Purpose Embedded Development Platform Based On PXA270

XScale is a powerful ARM processor, which is widely used in handhelds, STBs, and network devices, etc. An all-prupose embedded development platform is built based on an XScale PXA270 processor.The architecture and features of PXA270 are described in detail. The PXA270 has more than 360 pins in a PBGA package, so 6-layer PCB is necessary. As the internal frequence reaches 533 MHz and the external frequence reaches 100 MHz, the advanced EDA tool PADS2005 was used to analyse and design the high speed multi-layers PCB. The core board is a minimum computer system, and the expanding board contains Ethernet interface, audio interface, touch screen interface, and TFT-LCD, etc. The all-popurse embedded hardware platform is composed of these two boards.The interface circuit between PXA270 and SHARP TFT LCD LQ035Q7DH01 is designed. The timing adaptor, the synchronous communication interface, the power sequence controller and the PWM backlight controller were implemented by a MAX II CPLD. As these function blocks were integrated into one device, much space and cost were saved.A new Bootloader based on an open source project was written for this new hardware platform. Hardware debug options were added and the CS8900A Ethernet support code was developed as well. The detail of PXA270 LCD controller registers setting and frame buffer operating are described, and the startup LOGO display is implemented.Linux2.4 kernel was modified to adapt to the new hardware platform. Several device drivers were developed, including network device, backlight control device, and debug LEDs. The stuctrue of Linux network device driver is introduced and implementation of the CS8900A driver is discussed in detail.The results of the test and verification show that the platform works correctly and stable. Generally speaking, it is a powerful embedded platform for the usual applictions.