STM32--USB詳細使用說明

***************（3）**************

1.獲取設備描述符

usb_int.c的文件里面

低優(yōu)先級中斷 在控制 中斷 批量傳輸下使用（在單緩沖模式下使用）
當一次正確的OUT,SETUP,IN數(shù)據(jù)傳輸完成后，硬件會自動設置此位為NAK狀態(tài)，使應用程序有足夠的時間處理完當前傳輸?shù)臄?shù)據(jù)后，響應下一個數(shù)據(jù)分組

void CTR_LP(void)
{
__IO uint16_t wEPVal = 0;

while (((wIstr = _GetISTR()) & ISTR_CTR) != 0)
{

EPindex = (uint8_t)(wIstr & ISTR_EP_ID);//讀出端點ID
if (EPindex == 0)//如果是端點0
{





SaveRState = _GetENDPOINT(ENDP0);//讀取端點0寄存器USB_EP0R
SaveTState = SaveRState & EPTX_STAT;//保存發(fā)送狀態(tài)位
SaveRState &= EPRX_STAT;//保存接受狀態(tài)位
_SetEPRxTxStatus(ENDP0,EP_RX_NAK,EP_TX_NAK);//端點以NAK分組響應所有的發(fā)送和接受請求（解釋在上面）

if ((wIstr & ISTR_DIR) == 0)//IN令牌，數(shù)據(jù)被取走

{



_ClearEP_CTR_TX(ENDP0);//清除正確發(fā)送標志位
In0_Process();//處理INT事件

_SetEPRxTxStatus(ENDP0,SaveRState,SaveTState);
return;
}
else
{

wEPVal = _GetENDPOINT(ENDP0);//得到端點0寄存器的數(shù)據(jù)
if ((wEPVal &EP_SETUP) != 0)//SETUP分組傳輸完成標志
{
_ClearEP_CTR_RX(ENDP0);
Setup0_Process();//處理SETUP事件

//程序會進入到這個函數(shù)里面

_SetEPRxTxStatus(ENDP0,SaveRState,SaveTState);
return;
}

else if ((wEPVal & EP_CTR_RX) != 0)
{
_ClearEP_CTR_RX(ENDP0);
Out0_Process();//處理OUT事件

_SetEPRxTxStatus(ENDP0,SaveRState,SaveTState);
return;
}
}
}
else//如果是除端點0以外的端點
{

wEPVal = _GetENDPOINT(EPindex);//得到相應端點寄存器值
if ((wEPVal & EP_CTR_RX) != 0)//檢測正確接收標志 PC-USB OUT int
{

_ClearEP_CTR_RX(EPindex);//清除相應的標志

(*pEpInt_OUT[EPindex-1])();//調(diào)用OUT int服務功能

}

if ((wEPVal & EP_CTR_TX) != 0)//檢測正確發(fā)送標志 USB-PC IN int
{

_ClearEP_CTR_TX(EPindex);//清除相應的標志

(*pEpInt_IN[EPindex-1])();//調(diào)用IN int服務功能
}

}

}
}

usb_coer.c的文件里面，主要是得到主機發(fā)來的標準請求命令

uint8_t Setup0_Process(void)
{

union
{
uint8_t* b;
uint16_t* w;
} pBuf;

#ifdef STM32F10X_CL
USB_OTG_EP *ep;
uint16_t offset = 0;
ep = PCD_GetOutEP(ENDP0);
pBuf.b = ep->xfer_buff;
#else
uint16_t offset = 1;
//得到接受緩沖區(qū)地址寄存器地址
pBuf.b = PMAAddr + (uint8_t *)(_GetEPRxAddr(ENDP0) * 2);
#endif

if (pInformation->ControlState != PAUSE)
{
pInformation->USBbmRequestType = *pBuf.b++;

pInformation->USBbRequest = *pBuf.b++;

pBuf.w += offset;
pInformation->USBwValue = ByteSwap(*pBuf.w++);

pBuf.w += offset;
pInformation->USBwIndex = ByteSwap(*pBuf.w++);

pBuf.w += offset;
pInformation->USBwLength = *pBuf.w;

}

pInformation->ControlState = SETTING_UP;
if (pInformation->USBwLength == 0)
{

NoData_Setup0();
}
else
{

Data_Setup0();//由于是有數(shù)據(jù)的傳輸，所有要進入到這個函數(shù)
}
return Post0_Process();
}

usb_core.c的文件里面，這里只是選取了GET DESCRIPTOR

的程序部分，其他的部分刪除了

void Data_Setup0(void)
{
uint8_t *(*CopyRoutine)(uint16_t);
RESULT Result;
uint32_t Request_No = pInformation->USBbRequest;

uint32_t Related_Endpoint, Reserved;
uint32_t wOffset, Status;

CopyRoutine = NULL;
wOffset = 0;

//看標準請求碼格式就知道了
if (Request_No == GET_DESCRIPTOR)
{
//pInformation->USBbmRequestType是下面的兩種 標準請求或設備請求
if (Type_Recipient == (STANDARD_REQUEST | DEVICE_RECIPIENT))
{
uint8_t wValue1 = pInformation->USBwValue1;//高一字節(jié)得到描述表種類 一共有5種
if (wValue1 == DEVICE_DESCRIPTOR)//設備描述
{
CopyRoutine = pProperty->GetDeviceDescriptor;
}
else if (wValue1 == CONFIG_DESCRIPTOR)
{
CopyRoutine = pProperty->GetConfigDescriptor;//配置描述
}
else if (wValue1 == STRING_DESCRIPTOR)
{
CopyRoutine = pProperty->GetStringDescriptor;//字符串描述
}
}
}

if (CopyRoutine)
{
pInformation->Ctrl_Info.Usb_wOffset = wOffset;//本子程序的wOffset是0
pInformation->Ctrl_Info.CopyData = CopyRoutine;//使指針pInformation->Ctrl_Info.CopyData指向CopyRoutine


(*CopyRoutine)(0);//第一次執(zhí)行時Length=0 返回的是有效數(shù)據(jù)的長度 存儲到pInformation->Ctrl_Info.Usb_wLength
Result = USB_SUCCESS;
}
else
{//如果標準請求不存在 看類 廠商請求中是否有
Result = (*pProperty->Class_Data_Setup)(pInformation->USBbRequest);
if (Result == USB_NOT_READY)
{
pInformation->ControlState = PAUSE;
return;
}
}

if (pInformation->Ctrl_Info.Usb_wLength == 0xFFFF)//如果字符的長度是0xffff
{

pInformation->ControlState = PAUSE;
return;
}
if ((Result == USB_UNSUPPORT) || (pInformation->Ctrl_Info.Usb_wLength == 0))
{

pInformation->ControlState = STALLED;
return;
}

if (ValBit(pInformation->USBbmRequestType, 7))//D7表示數(shù)據(jù)傳輸方向 1：設備向主機
{

__IO uint32_t wLength = pInformation->USBwLength;

//設置使其為USB主機設置的長度 本程序HID 鼠標 pProperty->MaxPacketSize是0x40
if (pInformation->Ctrl_Info.Usb_wLength > wLength)//字符的長度大于主機要求的長度

{
pInformation->Ctrl_Info.Usb_wLength = wLength;

//將其設置為主機要求的
}
else if (pInformation->Ctrl_Info.Usb_wLength < pInformation->USBwLength)//字符的長度小于主機要求的
{
if (pInformation->Ctrl_Info.Usb_wLength < pProperty->MaxPacketSize) //如果字符的長度長度小于每包數(shù)據(jù)最大字節(jié)數(shù)
{
Data_Mul_MaxPacketSize = FALSE;
}
else if ((pInformation->Ctrl_Info.Usb_wLength % pProperty->MaxPacketSize) == 0)//如果是其整數(shù)倍
{
Data_Mul_MaxPacketSize = TRUE;
}
}

pInformation->Ctrl_Info.PacketSize = pProperty->MaxPacketSize;
DataStageIn();
}
else//主機向設備
{
pInformation->ControlState = OUT_DATA;
vSetEPRxStatus(EP_RX_VALID);
}

return;
}

usb_coer.c的文件里面

void DataStageIn(void)
{
ENDPOINT_INFO *pEPinfo = &pInformation->Ctrl_Info;//端點信息保存在指針變量中
uint32_t save_wLength = pEPinfo->Usb_wLength;//得到字符的長度
uint32_t ControlState = pInformation->ControlState;//得到當前的狀態(tài)

uint8_t *DataBuffer;
uint32_t Length;

if ((save_wLength == 0) && (ControlState == LAST_IN_DATA))//如果字符長度為0 且控制狀態(tài)是最后輸入的數(shù)據(jù)
{
if(Data_Mul_MaxPacketSize == TRUE)//如果字符的長度是數(shù)據(jù)包的整數(shù)倍
{

Send0LengthData();
ControlState = LAST_IN_DATA;
Data_Mul_MaxPacketSize = FALSE;//這一次發(fā)送0字節(jié) 狀態(tài)轉(zhuǎn)為最后輸入階段
}
else//字符的長度比數(shù)據(jù)包要小
{//數(shù)據(jù)已經(jīng)發(fā)送完

ControlState = WAIT_STATUS_OUT;

#ifdef STM32F10X_CL
PCD_EP_Read (ENDP0, 0, 0);
#endif
#ifndef STM32F10X_CL
vSetEPTxStatus(EP_TX_STALL);//設置端點的發(fā)送狀態(tài)停止
#endif
}
goto Expect_Status_Out;
}

Length = pEPinfo->PacketSize;//得到數(shù)據(jù)包大小 64字節(jié)
ControlState = (save_wLength <= Length) ? LAST_IN_DATA : IN_DATA;//比較大小得到是LAST_IN_DATA還是IN_DATA 18字節(jié)<64字節(jié) ControlState = LAST_IN_DATA

if (Length > save_wLength)
{
Length = save_wLength;
}

DataBuffer = (*pEPinfo->CopyData)(Length);//DataBuffer指向要復制數(shù)據(jù)的地址 這個地址是隨Usb_wOffset變化的

#ifdef STM32F10X_CL
PCD_EP_Write (ENDP0, DataBuffer, Length);
#else
//GetEPTxAddr(ENDP0) 得到發(fā)送緩沖區(qū)相應端點的地址
//將DataBuffer中的數(shù)據(jù)復制到相應的發(fā)送緩沖區(qū)中
UserToPMABufferCopy(DataBuffer, GetEPTxAddr(ENDP0), Length);
#endif

SetEPTxCount(ENDP0, Length);//設置相應的端點要發(fā)送的字節(jié)數(shù)

pEPinfo->Usb_wLength -= Length;//等于0
pEPinfo->Usb_wOffset += Length;//偏移到18
vSetEPTxStatus(EP_TX_VALID);//使能發(fā)送端點 只要主機的IN令牌包一來 SIE就會將描述符返回給主機

USB_StatusOut();
//設置接收端點有效 這個實際上使接受也有效，

Expect_Status_Out:
pInformation->ControlState = ControlState;//保存控制狀態(tài)
}

***************（4）**************

uint8_t In0_Process(void)
{
uint32_t ControlState = pInformation->ControlState;

if ((ControlState == IN_DATA) || (ControlState ==LAST_IN_DATA))//進入到這里

{
DataStageIn();//第一次取設備描述符只取一次當前的狀態(tài)變?yōu)閃AIT_STATUS_IN表明設備等待狀態(tài)過程 主機輸出0字節(jié)

ControlState = pInformation->ControlState;
}

else if (ControlState == WAIT_STATUS_IN)//設置地址狀態(tài)階段進入這個程序
{
if ((pInformation->USBbRequest == SET_ADDRESS) &&
(Type_Recipient == (STANDARD_REQUEST | DEVICE_RECIPIENT)))
{
SetDeviceAddress(pInformation->USBwValue0);//設置使用新的地址
pUser_Standard_Requests->User_SetDeviceAddress();
}
(*pProperty->Process_Status_IN)();
ControlState = STALLED;//變?yōu)檫@個狀態(tài)
}

else
{
ControlState = STALLED;
}

pInformation->ControlState = ControlState;

return Post0_Process();
}