Application Study And Software Development On Interface Technology Of PXA27x Chip Based On XScale Core

The Intel PXA27x processor facing multimedia application provides sufficient interfaces for XScale core. It has certain theory significance on research of interface techniques. And it has important practical value to develop interface software and to implement to the development of handheld and handset device.This article focused on I~2 C serial bus interface, I~2 S audio interface, LCD controller interface and keypad interface of PXA27x processor, and developed interface drivers of embedded linux operating system in linux circumstances.Major progress of this article includes:(1) Thoroughly studied I~2 C bus protocol, and realized the control and data transmission from processor to power module and audio module.(2) Studied programming techniques of I~2 S bus protocol, designed the I~2 S bus connection of audio device, made a breakthrough to the old connecting ways using AC'97 protocol.(3) Designed a programming model using kernel thread in touch screen driver, which replaced the old state machine model.The audio interface software designed in this article supports audio Codec using I~2 C interface and I~2 S interface, supports multiple sampling frequency up to 48 khz and functions including configuration of microphone , speaker, and handset. LCD of 16-color depth and 320×240 pixels resolution is supported by LCD controller interface software; 4-wire resistive touch screen is supported by PWRI~2 C bus interface software; 30-key matrix keypad is supported by keypad interface software.