/*This is the core function called by application to handle the MSC SCSI state
* machine */
BYTE USBMSC_poll ()
{
BYTE edbIndex;
edbIndex = stUsbHandle[MSC0_INTFNUM].edb_Index;
//check if currently transmitting data..
if (MscReadControl.bReadProcessing == TRUE){
BYTE bGIE;
bGIE = (__get_SR_register() & GIE); //save interrupt status
//atomic operation - disable interrupts
_DINT_FET(); //Disable global interrupts
if ((MscReadControl.dwBytesToSendLeft == 0) &&
(MscReadControl.lbaCount == 0)){
//data is no more processing - clear flags..
MscReadControl.bReadProcessing = FALSE;
__bis_SR_register(bGIE); //restore interrupt status
} else {
if (!(tInputEndPointDescriptorBlock[edbIndex].bEPCNF &
EPCNF_STALL)){ //if it is not stalled - contiune communication
USBIEPIFG |= 1 << (edbIndex + 1); //trigger IN interrupt to finish data tranmition
}
__bis_SR_register(bGIE); //restore interrupt status
return (kUSBMSC_processBuffer);
}
}
if (MscState.isMSCConfigured == FALSE){
return (kUSBMSC_okToSleep);
}
if (!MscState.bMscSendCsw){
if (MscState.bMscCbwReceived){
if (Scsi_Verify_CBW() == SUCCESS){
//Successful reception of CBW
//Parse the CBW opcode and invoke the right command handler function
Scsi_Cmd_Parser(MSC0_INTFNUM);
MscState.bMscSendCsw = TRUE;
}
MscState.bMscCbwReceived = FALSE; //CBW is performed!
} else {
return (kUSBMSC_okToSleep);
}
//check if any of out pipes has pending data and trigger interrupt
if ((MscWriteControl.pCT1 != NULL) &&
((*MscWriteControl.pCT1 & EPBCNT_NAK ) ||
(*MscWriteControl.pCT2 & EPBCNT_NAK ))){
USBOEPIFG |= 1 << (edbIndex + 1); //trigger OUT interrupt again
return (kUSBMSC_okToSleep); //do not asleep, as data is coming in
//and follow up data perform will be required.
}
}
if (MscState.bMscSendCsw){
if (MscState.bMcsCommandSupported == TRUE){
//watiting till transport is finished!
if ((MscWriteControl.bWriteProcessing == FALSE) &&
(MscReadControl.bReadProcessing == FALSE) &&
(MscReadControl.lbaCount == 0)){
//Send CSW
if (SUCCESS == Scsi_Send_CSW(MSC0_INTFNUM)){
MscState.bMscSendCsw = FALSE;
return (kUSBMSC_okToSleep);
}
}
else {
MSCFromHostToBuffer();
}
}
}
return (kUSBMSC_processBuffer); //When MscState.bMcsCommandSupported = FALSE, bReadProcessing became true, and
//bWriteProcessing = true.
}
uint8_t USBMSC_pollCommand ()
{
uint16_t state;
uint8_t edbIndex;
uint8_t * pCT1;
uint8_t * pCT2;
edbIndex = stUsbHandle[MSC0_INTFNUM].edb_Index;
pCT1 = &tInputEndPointDescriptorBlock[edbIndex].bEPBCTX;
pCT2 = &tInputEndPointDescriptorBlock[edbIndex].bEPBCTY;
//check if currently transmitting data..
if (MscReadControl.bReadProcessing == TRUE){
state = usbDisableOutEndpointInterrupt(edbIndex);
//atomic operation - disable interrupts
if ((MscReadControl.dwBytesToSendLeft == 0) &&
(MscReadControl.lbaCount == 0)){
//data is no more processing - clear flags..
MscReadControl.bReadProcessing = FALSE;
usbRestoreOutEndpointInterrupt(state);
} else {
if (!(tInputEndPointDescriptorBlock[edbIndex].bEPCNF &
EPCNF_STALL)){ //if it is not stalled - contiune communication
USBIEPIFG |= 1 << (edbIndex + 1); //trigger IN interrupt to finish data tranmition
}
usbRestoreOutEndpointInterrupt(state);
return (USBMSC_PROCESS_BUFFER);
}
}
if (MscState.isMSCConfigured == FALSE){
return (USBMSC_OK_TO_SLEEP);
}
if (!MscState.bMscSendCsw){
if (MscState.bMscCbwReceived){
if (Scsi_Verify_CBW() == SUCCESS){
//Successful reception of CBW
//Parse the CBW opcode and invoke the right command handler function
Scsi_Cmd_Parser(MSC0_INTFNUM);
MscState.bMscSendCsw = TRUE;
}
MscState.bMscCbwReceived = FALSE; //CBW is performed!
} else {
return (USBMSC_OK_TO_SLEEP);
}
//check if any of out pipes has pending data and trigger interrupt
if ((MscWriteControl.pCT1 != NULL) &&
((*MscWriteControl.pCT1 & EPBCNT_NAK ) ||
(*MscWriteControl.pCT2 & EPBCNT_NAK ))){
USBOEPIFG |= 1 << (edbIndex + 1); //trigger OUT interrupt again
return (USBMSC_PROCESS_BUFFER); //do not asleep, as data is coming in
//and follow up data perform will be required.
}
}
if (MscState.bMscSendCsw){
if (MscState.bMcsCommandSupported == TRUE){
//watiting till transport is finished!
if ((MscWriteControl.bWriteProcessing == FALSE) &&
(MscReadControl.bReadProcessing == FALSE) &&
(MscReadControl.lbaCount == 0)){
//Send CSW
if (MscState.stallAtEndofTx == TRUE) {
if ((*pCT1 & EPBCNT_NAK) && (*pCT2 & EPBCNT_NAK)) {
MscState.stallAtEndofTx = FALSE;
usbStallInEndpoint(MSC0_INTFNUM);
}
}
else if (SUCCESS == Scsi_Send_CSW(MSC0_INTFNUM)){
MscState.bMscSendCsw = FALSE;
return (USBMSC_OK_TO_SLEEP);
}
}
else {
MSCFromHostToBuffer();
}
}
}
return (USBMSC_PROCESS_BUFFER); //When MscState.bMcsCommandSupported = FALSE, bReadProcessing became true, and
//bWriteProcessing = true.
}