spi接口设置.txt

本代码是串口扩展芯片GM814X在 Arm9—usos上使用的实例

void SPI_INIT(void)
{
//PORT A GROUP
//SPI_nCS   接核心板B64 处理器GPA18引脚
//SPI_RST   接核心板B63处理器GPA17引脚
//RS485T_nR接核心板B65处理器GPA19引脚
  rPCONA &= ~(0x7<<17); 
  rPDATA &= ~(0x7<<17);

// PORT B GROUP
//SPI_CLK  接核心板B16 处理器GPB2引脚
//SPI_DOUT 接核心板B17处理器GPB4引脚
  rPCONB &= ~(0x3<<4);//GPB2
  rPCONB |= 0x1<<4;  
  rPCONB &= ~(0x3<<8);//GPB4


//PORT E GROUP 
//SPI_DIN   接核心板B36处理器GPE13引脚
  rPCONE  &= ~(0x3<<26); 
  rPCONE  |= 0x1<<26); 

 //PORT G GROUP
//SPI_IRQ   接核心板A51处理器GPG2引脚
  rPCONG &= ~(0x3<<4);
  rPCONG |= 0x2<<4;
 }