diff --git a/Demos/Device/ClassDriver/DualVirtualSerial/DualVirtualSerial.c b/Demos/Device/ClassDriver/DualVirtualSerial/DualVirtualSerial.c
index cc8f92ccd6..53d7ce9fc8 100644
--- a/Demos/Device/ClassDriver/DualVirtualSerial/DualVirtualSerial.c
+++ b/Demos/Device/ClassDriver/DualVirtualSerial/DualVirtualSerial.c
@@ -101,12 +101,12 @@ int main(void)
CheckJoystickMovement();
/* Discard all received data on the first CDC interface */
- while (CDC_Device_BytesReceived(&VirtualSerial1_CDC_Interface))
- CDC_Device_ReceiveByte(&VirtualSerial1_CDC_Interface);
+ CDC_Device_ReceiveByte(&VirtualSerial1_CDC_Interface);
/* Echo all received data on the second CDC interface */
- while (CDC_Device_BytesReceived(&VirtualSerial2_CDC_Interface))
- CDC_Device_SendByte(&VirtualSerial2_CDC_Interface, CDC_Device_ReceiveByte(&VirtualSerial2_CDC_Interface));
+ int16_t ReceivedByte; = CDC_Device_ReceiveByte(&VirtualSerial2_CDC_Interface);
+ if (!(ReceivedByte < 0))
+ CDC_Device_SendByte(&VirtualSerial2_CDC_Interface, (uint8_t)ReceivedByte);
CDC_Device_USBTask(&VirtualSerial1_CDC_Interface);
CDC_Device_USBTask(&VirtualSerial2_CDC_Interface);
diff --git a/Demos/Device/ClassDriver/VirtualSerial/VirtualSerial.c b/Demos/Device/ClassDriver/VirtualSerial/VirtualSerial.c
index d76f8cf959..c87b33ca7e 100644
--- a/Demos/Device/ClassDriver/VirtualSerial/VirtualSerial.c
+++ b/Demos/Device/ClassDriver/VirtualSerial/VirtualSerial.c
@@ -83,8 +83,7 @@ int main(void)
CheckJoystickMovement();
/* Must throw away unused bytes from the host, or it will lock up while waiting for the device */
- while (CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface))
- CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+ CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
USB_USBTask();
diff --git a/Demos/Device/ClassDriver/VirtualSerialMouse/VirtualSerialMouse.c b/Demos/Device/ClassDriver/VirtualSerialMouse/VirtualSerialMouse.c
index 8db86b84a2..6dfdafba70 100644
--- a/Demos/Device/ClassDriver/VirtualSerialMouse/VirtualSerialMouse.c
+++ b/Demos/Device/ClassDriver/VirtualSerialMouse/VirtualSerialMouse.c
@@ -97,8 +97,7 @@ int main(void)
CheckJoystickMovement();
/* Must throw away unused bytes from the host, or it will lock up while waiting for the device */
- while (CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface))
- CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+ CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
HID_Device_USBTask(&Mouse_HID_Interface);
diff --git a/Demos/Host/ClassDriver/VirtualSerialHost/VirtualSerialHost.c b/Demos/Host/ClassDriver/VirtualSerialHost/VirtualSerialHost.c
index 543e098252..c48694274f 100644
--- a/Demos/Host/ClassDriver/VirtualSerialHost/VirtualSerialHost.c
+++ b/Demos/Host/ClassDriver/VirtualSerialHost/VirtualSerialHost.c
@@ -111,10 +111,9 @@ int main(void)
if (CDC_Host_BytesReceived(&VirtualSerial_CDC_Interface))
{
/* Echo received bytes from the attached device through the USART */
- while (CDC_Host_BytesReceived(&VirtualSerial_CDC_Interface))
- putchar(CDC_Host_ReceiveByte(&VirtualSerial_CDC_Interface));
-
- CDC_Host_Flush(&VirtualSerial_CDC_Interface);
+ int16_t ReceivedByte = CDC_Host_ReceiveByte(&VirtualSerial_CDC_Interface);
+ if (!(ReceivedByte < 0))
+ putchar(ReceivedByte);
}
break;
diff --git a/LUFA/Drivers/USB/Class/Device/CDC.c b/LUFA/Drivers/USB/Class/Device/CDC.c
index 453d21d841..026ac269af 100644
--- a/LUFA/Drivers/USB/Class/Device/CDC.c
+++ b/LUFA/Drivers/USB/Class/Device/CDC.c
@@ -128,11 +128,6 @@ void CDC_Device_USBTask(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
{
if ((USB_DeviceState != DEVICE_STATE_Configured) || !(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS))
return;
-
- Endpoint_SelectEndpoint(CDCInterfaceInfo->Config.DataOUTEndpointNumber);
-
- if (Endpoint_IsOUTReceived() && !(Endpoint_BytesInEndpoint()))
- Endpoint_ClearOUT();
CDC_Device_Flush(CDCInterfaceInfo);
}
@@ -222,19 +217,24 @@ uint16_t CDC_Device_BytesReceived(USB_ClassInfo_CDC_Device_t* const CDCInterface
}
}
-uint8_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
+int16_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
{
+ uint8_t ReceivedByte = -1;
+
if ((USB_DeviceState != DEVICE_STATE_Configured) || !(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS))
return 0;
Endpoint_SelectEndpoint(CDCInterfaceInfo->Config.DataOUTEndpointNumber);
- uint8_t DataByte = Endpoint_Read_Byte();
+ if (!(Endpoint_IsOUTReceived()))
+ return -1;
+ else if (Endpoint_BytesInEndpoint())
+ ReceivedByte = Endpoint_Read_Byte();
if (!(Endpoint_BytesInEndpoint()))
Endpoint_ClearOUT();
-
- return DataByte;
+
+ return ReceivedByte;
}
void CDC_Device_SendControlLineStateChange(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
@@ -282,24 +282,28 @@ static int CDC_Device_putchar(char c,
static int CDC_Device_getchar(FILE* Stream)
{
- if (!(CDC_Device_BytesReceived((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream))))
+ int16_t ReceivedByte = CDC_Device_ReceiveByte((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream));
+
+ if (ReceivedByte < 0)
return _FDEV_EOF;
- return CDC_Device_ReceiveByte((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream));
+ return ReceivedByte;
}
static int CDC_Device_getchar_Blocking(FILE* Stream)
{
- while (!(CDC_Device_BytesReceived((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream))))
+ int16_t ReceivedByte;
+
+ while ((ReceivedByte = CDC_Device_ReceiveByte((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream))) < 0)
{
if (USB_DeviceState == DEVICE_STATE_Unattached)
return _FDEV_EOF;
CDC_Device_USBTask((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream));
- USB_USBTask();
+ USB_USBTask();
}
- return CDC_Device_ReceiveByte((USB_ClassInfo_CDC_Device_t*)fdev_get_udata(Stream));
+ return ReceivedByte;
}
#endif
diff --git a/LUFA/Drivers/USB/Class/Device/CDC.h b/LUFA/Drivers/USB/Class/Device/CDC.h
index 9e92d5f6ce..3ada8f7afb 100644
--- a/LUFA/Drivers/USB/Class/Device/CDC.h
+++ b/LUFA/Drivers/USB/Class/Device/CDC.h
@@ -233,7 +233,10 @@
uint8_t CDC_Device_SendByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,
const uint8_t Data) ATTR_NON_NULL_PTR_ARG(1);
- /** Determines the number of bytes received by the CDC interface from the host, waiting to be read.
+ /** Determines the number of bytes received by the CDC interface from the host, waiting to be read. This indicates the number
+ * of bytes in the OUT endpoint bank only, and thus the number of calls to \ref CDC_Device_ReceiveByte() which are guaranteed to
+ * succeed immediately. If multiple bytes are to be received, they should be buffered by the user application, as the endpoint
+ * bank will not be released back to the USB controller until all bytes are read.
*
* \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
* the call will fail.
@@ -245,17 +248,18 @@
uint16_t CDC_Device_BytesReceived(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
/** Reads a byte of data from the host. If no data is waiting to be read of if a USB host is not connected, the function
- * returns 0. The \ref CDC_Device_BytesReceived() function should be queried before data is received to ensure that no data
- * underflow occurs.
+ * returns a negative value. The \ref CDC_Device_BytesReceived() function may be queried in advance to determine how many
+ * bytes are currently buffered in the CDC interface's data receive endpoint bank, and thus how many repeated calls to this
+ * function which are guaranteed to succeed.
*
* \pre This function must only be called when the Device state machine is in the DEVICE_STATE_Configured state or
* the call will fail.
*
* \param[in,out] CDCInterfaceInfo Pointer to a structure containing a CDC Class configuration and state.
*
- * \return Next received byte from the host, or 0 if no data received.
+ * \return Next received byte from the host, or a negative value if no data received.
*/
- uint8_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
+ int16_t CDC_Device_ReceiveByte(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
/** Flushes any data waiting to be sent, ensuring that the send buffer is cleared.
*
diff --git a/LUFA/Drivers/USB/Class/Host/CDC.c b/LUFA/Drivers/USB/Class/Host/CDC.c
index cf344beae2..5fb232c099 100644
--- a/LUFA/Drivers/USB/Class/Host/CDC.c
+++ b/LUFA/Drivers/USB/Class/Host/CDC.c
@@ -220,14 +220,19 @@ void CDC_Host_USBTask(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)
sizeof(CDCInterfaceInfo->State.ControlLineStates.DeviceToHost),
NO_STREAM_CALLBACK);
- }
-
- Pipe_ClearIN();
+ Pipe_ClearIN();
- EVENT_CDC_Host_ControLineStateChanged(CDCInterfaceInfo);
+ EVENT_CDC_Host_ControLineStateChanged(CDCInterfaceInfo);
+ }
+ else
+ {
+ Pipe_ClearIN();
+ }
}
Pipe_Freeze();
+
+ CDC_Host_Flush(CDCInterfaceInfo);
}
uint8_t CDC_Host_SetLineEncoding(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)
@@ -353,9 +358,9 @@ uint16_t CDC_Host_BytesReceived(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo
}
}
-uint8_t CDC_Host_ReceiveByte(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)
+int16_t CDC_Host_ReceiveByte(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)
{
- uint8_t ReceivedByte = 0;
+ uint8_t ReceivedByte = -1;
if ((USB_HostState != HOST_STATE_Configured) || !(CDCInterfaceInfo->State.IsActive))
return 0;
@@ -364,11 +369,14 @@ uint8_t CDC_Host_ReceiveByte(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)
Pipe_SetPipeToken(PIPE_TOKEN_IN);
Pipe_Unfreeze();
- ReceivedByte = Pipe_Read_Byte();
-
+ if (!(Pipe_IsINReceived()))
+ return -1;
+ else if (Pipe_BytesInPipe())
+ ReceivedByte = Pipe_Read_Byte();
+
if (!(Pipe_BytesInPipe()))
Pipe_ClearIN();
-
+
Pipe_Freeze();
return ReceivedByte;
@@ -426,15 +434,19 @@ static int CDC_Host_putchar(char c,
static int CDC_Host_getchar(FILE* Stream)
{
- if (!(CDC_Host_BytesReceived((USB_ClassInfo_CDC_Host_t*)fdev_get_udata(Stream))))
+ int16_t ReceivedByte = CDC_Host_ReceiveByte((USB_ClassInfo_CDC_Host_t*)fdev_get_udata(Stream));
+
+ if (ReceivedByte < 0)
return _FDEV_EOF;
- return CDC_Host_ReceiveByte((USB_ClassInfo_CDC_Host_t*)fdev_get_udata(Stream));
+ return ReceivedByte;
}
static int CDC_Host_getchar_Blocking(FILE* Stream)
{
- while (!(CDC_Host_BytesReceived((USB_ClassInfo_CDC_Host_t*)fdev_get_udata(Stream))))
+ int16_t ReceivedByte;
+
+ while ((ReceivedByte = CDC_Host_ReceiveByte((USB_ClassInfo_CDC_Host_t*)fdev_get_udata(Stream))) < 0)
{
if (USB_HostState == HOST_STATE_Unattached)
return _FDEV_EOF;
@@ -443,7 +455,7 @@ static int CDC_Host_getchar_Blocking(FILE* Stream)
USB_USBTask();
}
- return CDC_Host_ReceiveByte((USB_ClassInfo_CDC_Host_t*)fdev_get_udata(Stream));
+ return ReceivedByte;
}
void CDC_Host_Event_Stub(void)
diff --git a/LUFA/Drivers/USB/Class/Host/CDC.h b/LUFA/Drivers/USB/Class/Host/CDC.h
index 640242819f..56bcf31477 100644
--- a/LUFA/Drivers/USB/Class/Host/CDC.h
+++ b/LUFA/Drivers/USB/Class/Host/CDC.h
@@ -236,7 +236,10 @@
uint8_t CDC_Host_SendByte(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo,
const uint8_t Data) ATTR_NON_NULL_PTR_ARG(1);
- /** Determines the number of bytes received by the CDC interface from the device, waiting to be read.
+ /** Determines the number of bytes received by the CDC interface from the device, waiting to be read. This indicates the number
+ * of bytes in the IN pipe bank only, and thus the number of calls to \ref CDC_Host_ReceiveByte() which are guaranteed to succeed
+ * immediately. If multiple bytes are to be received, they should be buffered by the user application, as the pipe bank will not be
+ * released back to the USB controller until all bytes are read.
*
* \pre This function must only be called when the Host state machine is in the HOST_STATE_Configured state or the
* call will fail.
@@ -248,17 +251,17 @@
uint16_t CDC_Host_BytesReceived(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
/** Reads a byte of data from the device. If no data is waiting to be read of if a USB device is not connected, the function
- * returns 0. The \ref CDC_Host_BytesReceived() function should be queried before data is received to ensure that no data
- * underflow occurs.
+ * returns a negative value. The \ref CDC_Host_BytesReceived() function may be queried in advance to determine how many bytes
+ * are currently buffered in the CDC interface's data receive pipe.
*
* \pre This function must only be called when the Host state machine is in the HOST_STATE_Configured state or the
* call will fail.
*
* \param[in,out] CDCInterfaceInfo Pointer to a structure containing a CDC Class host configuration and state.
*
- * \return Next received byte from the device, or 0 if no data received.
+ * \return Next received byte from the device, or a negative value if no data received.
*/
- uint8_t CDC_Host_ReceiveByte(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
+ int16_t CDC_Host_ReceiveByte(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
/** Flushes any data waiting to be sent, ensuring that the send buffer is cleared.
*
diff --git a/LUFA/ManPages/ChangeLog.txt b/LUFA/ManPages/ChangeLog.txt
index c410ca6d84..b234bfcbe0 100644
--- a/LUFA/ManPages/ChangeLog.txt
+++ b/LUFA/ManPages/ChangeLog.txt
@@ -41,6 +41,8 @@
* - Internal USB driver source files renamed and moved to ease future possible architecture ports
* - All internal pseudo-function macros have been converted to true inline functions for type-safety and readability
* - Changed LED indicator masks for the AVRISP-MKII project, so that there are defined roles for each LED
+ * - Altered the CDC Deivice and Host Class drivers' receive byte routines, so that no data is indicated by a negative return value
+ * - Added auto flushing of OUT data to the CDC Host Class driver's USBTask function to automatically flush the send pipe buffer
*
* Fixed:
* - Fixed AVRISP project sending a LOAD EXTENDED ADDRESS command to 128KB AVRs after programming or reading from
diff --git a/LUFA/ManPages/MigrationInformation.txt b/LUFA/ManPages/MigrationInformation.txt
index d3453326c1..2a0d0c5333 100644
--- a/LUFA/ManPages/MigrationInformation.txt
+++ b/LUFA/ManPages/MigrationInformation.txt
@@ -32,6 +32,16 @@
* enhanced \ref USB_Device_SendRemoteWakeup() function. Existing code may now discard any checks to USB_Device_IsRemoteWakeupSent().
* - The USB_Device_IsUSBSuspended() macro has been removed, as it is obsolete. Existing code should compare \ref USB_DeviceState
* to see if it the device is in the \ref DEVICE_STATE_Suspended state instead.
+ * - The \ref CDC_Device_ReceiveByte() function has changed, and now returns a signed 16-bit integer, with -1 indicating no data was
+ * received. This allows for more efficient coding, as a call to \ref CDC_Device_BytesReceived() is no longer needed if the exact
+ * number of queued bytes received is not needed.
+ *
+ * Host Mode
+ * - The \ref CDC_Host_ReceiveByte() function has changed, and now returns a signed 16-bit integer, with -1 indicating no data was
+ * received. This allows for more efficient coding, as a call to \ref CDC_Device_BytesReceived() is no longer needed if the exact
+ * number of queued bytes received is not needed.
+ * - The \ref CDC_Host_USBTask() now calls \ref CDC_Host_Flush() automatically, flushing any queued data to the attached device. Manual
+ * flushing of the interface is no longer needed if the flushes should be in sync with calls to \ref CDC_Host_USBTask().
*
* \section Sec_Migration100513 Migrating from 100219 to 100513
*
diff --git a/Projects/Benito/Benito.c b/Projects/Benito/Benito.c
index 23786fb9e0..ac1e064d58 100644
--- a/Projects/Benito/Benito.c
+++ b/Projects/Benito/Benito.c
@@ -92,9 +92,10 @@ int main(void)
for (;;)
{
/* Echo bytes from the host to the target via the hardware USART */
- if (CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface) && (UCSR1A & (1 << UDRE1)))
+ int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+ if (!(ReceivedByte < 0) && (UCSR1A & (1 << UDRE1)))
{
- UDR1 = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+ UDR1 = ReceivedByte;
LEDs_TurnOnLEDs(LEDMASK_TX);
PulseMSRemaining.TxLEDPulse = TX_RX_LED_PULSE_MS;
diff --git a/Projects/USBtoSerial/USBtoSerial.c b/Projects/USBtoSerial/USBtoSerial.c
index 2c2d0c0069..d7df3d91fb 100644
--- a/Projects/USBtoSerial/USBtoSerial.c
+++ b/Projects/USBtoSerial/USBtoSerial.c
@@ -82,13 +82,9 @@ int main(void)
for (;;)
{
/* Read bytes from the USB OUT endpoint into the USART transmit buffer */
- for (uint8_t DataBytesRem = CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface); DataBytesRem != 0; DataBytesRem--)
- {
- if (RingBuffer_IsFull(&USBtoUSART_Buffer))
- break;
-
- RingBuffer_AtomicInsert(&USBtoUSART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
- }
+ int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+ if (!(ReceivedByte < 0) && !(RingBuffer_IsFull(&USBtoUSART_Buffer)))
+ RingBuffer_AtomicInsert(&USBtoUSART_Buffer, (uint8_t)ReceivedByte);
/* Check if the software USART flush timer has expired */
if (TIFR0 & (1 << TOV0))
diff --git a/Projects/XPLAINBridge/XPLAINBridge.c b/Projects/XPLAINBridge/XPLAINBridge.c
index 28354812f5..7a1bcb34de 100644
--- a/Projects/XPLAINBridge/XPLAINBridge.c
+++ b/Projects/XPLAINBridge/XPLAINBridge.c
@@ -120,7 +120,8 @@ void UARTBridge_Task(void)
return;
/* Read bytes from the USB OUT endpoint into the UART transmit buffer */
- if (CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface) && !(RingBuffer_IsFull(&USBtoUART_Buffer)))
+ int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+ if (!(ReceivedByte < 0) && !(RingBuffer_IsFull(&USBtoUART_Buffer)))
RingBuffer_AtomicInsert(&USBtoUART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
/* Check if the software UART flush timer has expired */