PXA270平台上自定义GPIO中断的实现

Implementation of the User-defined GPIO Interrupt Based on PXA270

为了使用PXA270的GPIO引脚实现按键中断,必须在Windows CE下建立自定义GPIO的中断机制.对PXA270中断系统的硬件结构和Windows CE操作系统下的中断处理流程进行了分析,提出了物理中断号和逻辑中断号的概念,给出了驱动程序开发的IST模型.在此基础上通过修改原始设备制造商适配层(OAL)代码及设备驱动层的关键函数,实现了在PXA270应用平台上添加一个用户自定义GPIO中断,建立了该中断的执行机制,从而为键盘驱动程序开发奠定了基础.

In order to use one of the PXA270 GPIO pins to achieve the key interrupt,interrupt mechanism for GPIO is built.The hardware architecture of PXA270 interrupt system and the interrupt handling mechanism of Windows CE are discussed,and then the concept physical interrupt identifier and the logic interrupt identifier are proposed.The IST model of driver development is also discussed.By modifying the OAL code and the key functions of device driver,one can add a user-defined GPIO interrupt on the PXA270 application platform and establish the enforcement mechanism of the user-defined GPIO interrupt,which becomes the basis for the development of the keyboard driver.