2440下的USB實(shí)驗

{
U8 usbdIntpnd, epIntpnd;
U8 saveIndexReg = rINDEX_REG; //保存索引寄存器值(現場(chǎng)保護)
usbdIntpnd = rUSB_INT_REG;//保存中斷標志寄存器
epIntpnd = rEP_INT_REG;

if(usbdIntpnd&SUSPEND_INT)//總線(xiàn)上超過(guò) 3ms 沒(méi)有活動(dòng)信號引起中斷
{
rUSB_INT_REG = SUSPEND_INT;//清除中斷標志位
}

if(usbdIntpnd&RESUME_INT)
{
rUSB_INT_REG = RESUME_INT; //恢復引起的中斷
}

if(usbdIntpnd&RESET_INT)//接收到復位信號引起的中斷
{
//ResetUsbd();
ReconfigUsbd();//重新配置 USB device
rUSB_INT_REG = RESET_INT; //RESET_INT should be cleared after ResetUsbd().
PrepareEp1Fifo();
}

if(epIntpnd&EP0_INT)//端點(diǎn) 0 中斷
{
rEP_INT_REG = EP0_INT;
Ep0Handler();//進(jìn)入控制傳輸中斷處理程序
}

if(epIntpnd&EP1_INT)
{
rEP_INT_REG=EP1_INT;
Ep1Handler();//進(jìn)入 Ep1 中斷處理程序(BULK IN)
}

if(epIntpnd&EP2_INT)
{
rEP_INT_REG = EP2_INT;
//Ep2Handler();
}

if(epIntpnd&EP3_INT)
{
rEP_INT_REG = EP3_INT;
Ep3Handler();//進(jìn)入 Ep3 中斷處理程序(BULK OUT)
}

if(epIntpnd&EP4_INT)
{
rEP_INT_REG = EP4_INT;
//Ep4Handler();
}

ClearPending(BIT_USBD);//USB 設備中斷處理完畢，清除中斷標志位
rINDEX_REG = saveIndexReg;//恢復索引寄存器原來(lái)的值(恢復現場(chǎng))
}

6.2 端點(diǎn) 1 的數據傳輸程序

void Ep1Handler(void)

{
U8 in_csr1;

rINDEX_REG = 1;

in_csr1 = rIN_CSR1_REG;

//I think that EPI_SENT_STALL will not be set to 1.
if(in_csr1 & EPI_SENT_STALL) //USB 已經(jīng)發(fā)布了一個(gè) STALL 握手信號，由此引起該中斷

{
CLR_EP1_SENT_STALL();//清除 SENT_STALL 位，STALL 狀態(tài)結束

return;

}

//IN_PKT_READY is cleared

//The data transfered was ep1Buf[] which was already configured transferIndex++;
if(UsbState==0x01234567)
PrepareEp1Fifo();//準備好發(fā)送的數據，把 IN_PKT_READY 置位

//IN_PKT_READY is set

//This packit will be used for next IN packit.

return;

}

6.3 USB Device 初始化函數

void UsbdInit(U8 fun)

{

isUsbdSetConfiguration = 0;

//MDIV=40,PDIV=4,SDIV=1

//Upll = (m * Fin) / (p * 2**s)

//m = (MDIV + 8), p = (PDIV + 2), s = SDIV

//Upll=48MHz

rUPLLCON = (40<<12) | (4<<4) | 1;
//初始化描述符 InitDescriptorTable(fun); ReconfigUsbd();

UsbState = 0;
}

6.4 USB 下載函數

static int BoardUsbDownload(U32 addr, U32 run)

{

U8 fun;

int len;

//GPH9-->output GPH10-->output

rGPHCON = rGPHCON&~(0xf<<18)|(0x5<<18);

//GPG9-->input

rGPGCON &= 0xfff3ffff;

fun = 1;
//USB Device 初始化 UsbdInit(fun); Delay(100);
//GPG9-->output rGPGCON |= 0x00040000;
//GPG9 ouput 1
rGPGDAT |= 0x0200;

//中斷服務(wù)程序
pISR_USBD =(unsigned)IsrUsbd; ClearPending(BIT_USBD); EnableIrq(BIT_USBD);
len = WaitDownload(addr); DisableIrq(BIT_USBD);
rGPGCON &= 0xfff3ffff;//GPG9 input

if(len>0) {

Uart_Printf("nUSB download finished,press any key to exitn");

}

return len;

}