Add tag for the 120219 release.
[pub/USBasp.git] / Projects / USBtoSerial / USBtoSerial.c
index 1b4cab2..194f6b0 100644 (file)
-/*\r
-             LUFA Library\r
-     Copyright (C) Dean Camera, 2010.\r
-              \r
-  dean [at] fourwalledcubicle [dot] com\r
-      www.fourwalledcubicle.com\r
-*/\r
-\r
-/*\r
-  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)\r
-\r
-  Permission to use, copy, modify, distribute, and sell this \r
-  software and its documentation for any purpose is hereby granted\r
-  without fee, provided that the above copyright notice appear in \r
-  all copies and that both that the copyright notice and this\r
-  permission notice and warranty disclaimer appear in supporting \r
-  documentation, and that the name of the author not be used in \r
-  advertising or publicity pertaining to distribution of the \r
-  software without specific, written prior permission.\r
-\r
-  The author disclaim all warranties with regard to this\r
-  software, including all implied warranties of merchantability\r
-  and fitness.  In no event shall the author be liable for any\r
-  special, indirect or consequential damages or any damages\r
-  whatsoever resulting from loss of use, data or profits, whether\r
-  in an action of contract, negligence or other tortious action,\r
-  arising out of or in connection with the use or performance of\r
-  this software.\r
-*/\r
-\r
-/** \file\r
- *\r
- *  Main source file for the USBtoSerial project. This file contains the main tasks of\r
- *  the demo and is responsible for the initial application hardware configuration.\r
- */\r
-\r
-#include "USBtoSerial.h"\r
-\r
-/** Circular buffer to hold data from the host before it is sent to the device via the serial port. */\r
-RingBuff_t USBtoUSART_Buffer;\r
-\r
-/** Circular buffer to hold data from the serial port before it is sent to the host. */\r
-RingBuff_t USARTtoUSB_Buffer;\r
-\r
-/** LUFA CDC Class driver interface configuration and state information. This structure is\r
- *  passed to all CDC Class driver functions, so that multiple instances of the same class\r
- *  within a device can be differentiated from one another.\r
- */\r
-USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =\r
-       {\r
-               .Config = \r
-                       {\r
-                               .ControlInterfaceNumber         = 0,\r
-\r
-                               .DataINEndpointNumber           = CDC_TX_EPNUM,\r
-                               .DataINEndpointSize             = CDC_TXRX_EPSIZE,\r
-                               .DataINEndpointDoubleBank       = false,\r
-\r
-                               .DataOUTEndpointNumber          = CDC_RX_EPNUM,\r
-                               .DataOUTEndpointSize            = CDC_TXRX_EPSIZE,\r
-                               .DataOUTEndpointDoubleBank      = false,\r
-\r
-                               .NotificationEndpointNumber     = CDC_NOTIFICATION_EPNUM,\r
-                               .NotificationEndpointSize       = CDC_NOTIFICATION_EPSIZE,\r
-                               .NotificationEndpointDoubleBank = false,\r
-                       },\r
-       };\r
-\r
-/** Main program entry point. This routine contains the overall program flow, including initial\r
- *  setup of all components and the main program loop.\r
- */\r
-int main(void)\r
-{\r
-       SetupHardware();\r
-       \r
-       Buffer_Initialize(&USBtoUSART_Buffer);\r
-       Buffer_Initialize(&USARTtoUSB_Buffer);\r
-\r
-       LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);\r
-       sei();\r
-\r
-       for (;;)\r
-       {\r
-               /* Read bytes from the USB OUT endpoint into the USART transmit buffer */\r
-               for (uint8_t DataBytesRem = CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface); DataBytesRem != 0; DataBytesRem--)\r
-               {\r
-                       if (!(BUFF_STATICSIZE - USBtoUSART_Buffer.Elements))\r
-                         break;\r
-                         \r
-                       Buffer_StoreElement(&USBtoUSART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));\r
-               }\r
-               \r
-               /* Read bytes from the USART receive buffer into the USB IN endpoint */\r
-               while (USARTtoUSB_Buffer.Elements)\r
-                 CDC_Device_SendByte(&VirtualSerial_CDC_Interface, Buffer_GetElement(&USARTtoUSB_Buffer));\r
-               \r
-               /* Load bytes from the USART transmit buffer into the USART */\r
-               while (USBtoUSART_Buffer.Elements)\r
-                 Serial_TxByte(Buffer_GetElement(&USBtoUSART_Buffer));\r
-               \r
-               CDC_Device_USBTask(&VirtualSerial_CDC_Interface);\r
-               USB_USBTask();\r
-       }\r
-}\r
-\r
-/** Configures the board hardware and chip peripherals for the demo's functionality. */\r
-void SetupHardware(void)\r
-{\r
-       /* Disable watchdog if enabled by bootloader/fuses */\r
-       MCUSR &= ~(1 << WDRF);\r
-       wdt_disable();\r
-\r
-       /* Disable clock division */\r
-       clock_prescale_set(clock_div_1);\r
-\r
-       /* Hardware Initialization */\r
-       Serial_Init(9600, false);\r
-       LEDs_Init();\r
-       USB_Init();\r
-}\r
-\r
-/** Event handler for the library USB Connection event. */\r
-void EVENT_USB_Device_Connect(void)\r
-{\r
-       LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);\r
-}\r
-\r
-/** Event handler for the library USB Disconnection event. */\r
-void EVENT_USB_Device_Disconnect(void)\r
-{\r
-       LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);\r
-}\r
-\r
-/** Event handler for the library USB Configuration Changed event. */\r
-void EVENT_USB_Device_ConfigurationChanged(void)\r
-{\r
-       LEDs_SetAllLEDs(LEDMASK_USB_READY);\r
-\r
-       if (!(CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface)))\r
-         LEDs_SetAllLEDs(LEDMASK_USB_ERROR);\r
-}\r
-\r
-/** Event handler for the library USB Unhandled Control Request event. */\r
-void EVENT_USB_Device_UnhandledControlRequest(void)\r
-{\r
-       CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);\r
-}\r
-\r
-/** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer\r
- *  for later transmission to the host.\r
- */\r
-ISR(USART1_RX_vect, ISR_BLOCK)\r
-{\r
-       uint8_t ReceivedByte = UDR1;\r
-\r
-       if (USB_DeviceState == DEVICE_STATE_Configured)\r
-         Buffer_StoreElement(&USARTtoUSB_Buffer, ReceivedByte);\r
-}\r
-\r
-/** Event handler for the CDC Class driver Line Encoding Changed event.\r
- *\r
- *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced\r
- */\r
-void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)\r
-{\r
-       uint8_t ConfigMask = 0;\r
-\r
-       switch (CDCInterfaceInfo->State.LineEncoding.ParityType)\r
-       {\r
-               case CDC_PARITY_Odd:\r
-                       ConfigMask = ((1 << UPM11) | (1 << UPM10));             \r
-                       break;\r
-               case CDC_PARITY_Even:\r
-                       ConfigMask = (1 << UPM11);              \r
-                       break;\r
-       }\r
-\r
-       if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)\r
-         ConfigMask |= (1 << USBS1);\r
-\r
-       switch (CDCInterfaceInfo->State.LineEncoding.DataBits)\r
-       {\r
-               case 6:\r
-                       ConfigMask |= (1 << UCSZ10);\r
-                       break;\r
-               case 7:\r
-                       ConfigMask |= (1 << UCSZ11);\r
-                       break;\r
-               case 8:\r
-                       ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));\r
-                       break;\r
-       }\r
-       \r
-       UCSR1A = (1 << U2X1);   \r
-       UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));\r
-       UCSR1C = ConfigMask;    \r
-       UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);\r
-}\r
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2012.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2012  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaim all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *
+ *  Main source file for the USBtoSerial project. This file contains the main tasks of
+ *  the project and is responsible for the initial application hardware configuration.
+ */
+
+#include "USBtoSerial.h"
+
+/** Circular buffer to hold data from the host before it is sent to the device via the serial port. */
+static RingBuffer_t USBtoUSART_Buffer;
+
+/** Underlying data buffer for \ref USBtoUSART_Buffer, where the stored bytes are located. */
+static uint8_t      USBtoUSART_Buffer_Data[128];
+
+/** Circular buffer to hold data from the serial port before it is sent to the host. */
+static RingBuffer_t USARTtoUSB_Buffer;
+
+/** Underlying data buffer for \ref USARTtoUSB_Buffer, where the stored bytes are located. */
+static uint8_t      USARTtoUSB_Buffer_Data[128];
+
+/** LUFA CDC Class driver interface configuration and state information. This structure is
+ *  passed to all CDC Class driver functions, so that multiple instances of the same class
+ *  within a device can be differentiated from one another.
+ */
+USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =
+       {
+               .Config =
+                       {
+                               .ControlInterfaceNumber         = 0,
+
+                               .DataINEndpointNumber           = CDC_TX_EPNUM,
+                               .DataINEndpointSize             = CDC_TXRX_EPSIZE,
+                               .DataINEndpointDoubleBank       = false,
+
+                               .DataOUTEndpointNumber          = CDC_RX_EPNUM,
+                               .DataOUTEndpointSize            = CDC_TXRX_EPSIZE,
+                               .DataOUTEndpointDoubleBank      = false,
+
+                               .NotificationEndpointNumber     = CDC_NOTIFICATION_EPNUM,
+                               .NotificationEndpointSize       = CDC_NOTIFICATION_EPSIZE,
+                               .NotificationEndpointDoubleBank = false,
+                       },
+       };
+
+
+/** Main program entry point. This routine contains the overall program flow, including initial
+ *  setup of all components and the main program loop.
+ */
+int main(void)
+{
+       SetupHardware();
+
+       RingBuffer_InitBuffer(&USBtoUSART_Buffer, USBtoUSART_Buffer_Data, sizeof(USBtoUSART_Buffer_Data));
+       RingBuffer_InitBuffer(&USARTtoUSB_Buffer, USARTtoUSB_Buffer_Data, sizeof(USARTtoUSB_Buffer_Data));
+
+       LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
+       sei();
+
+       for (;;)
+       {
+               /* Only try to read in bytes from the CDC interface if the transmit buffer is not full */
+               if (!(RingBuffer_IsFull(&USBtoUSART_Buffer)))
+               {
+                       int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
+
+                       /* Read bytes from the USB OUT endpoint into the USART transmit buffer */
+                       if (!(ReceivedByte < 0))
+                         RingBuffer_Insert(&USBtoUSART_Buffer, ReceivedByte);
+               }
+
+               /* Check if the UART receive buffer flush timer has expired or the buffer is nearly full */
+               uint16_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer);
+               if ((TIFR0 & (1 << TOV0)) || (BufferCount > (uint8_t)(sizeof(USARTtoUSB_Buffer_Data) * .75)))
+               {
+                       /* Clear flush timer expiry flag */
+                       TIFR0 |= (1 << TOV0);
+
+                       /* Read bytes from the USART receive buffer into the USB IN endpoint */
+                       while (BufferCount--)
+                       {
+                               /* Try to send the next byte of data to the host, abort if there is an error without dequeuing */
+                               if (CDC_Device_SendByte(&VirtualSerial_CDC_Interface,
+                                                       RingBuffer_Peek(&USARTtoUSB_Buffer)) != ENDPOINT_READYWAIT_NoError)
+                               {
+                                       break;
+                               }
+
+                               /* Dequeue the already sent byte from the buffer now we have confirmed that no transmission error occurred */
+                               RingBuffer_Remove(&USARTtoUSB_Buffer);
+                       }
+               }
+
+               /* Load the next byte from the USART transmit buffer into the USART */
+               if (!(RingBuffer_IsEmpty(&USBtoUSART_Buffer)))
+                 Serial_SendByte(RingBuffer_Remove(&USBtoUSART_Buffer));
+
+               CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
+               USB_USBTask();
+       }
+}
+
+/** Configures the board hardware and chip peripherals for the demo's functionality. */
+void SetupHardware(void)
+{
+       /* Disable watchdog if enabled by bootloader/fuses */
+       MCUSR &= ~(1 << WDRF);
+       wdt_disable();
+
+       /* Disable clock division */
+       clock_prescale_set(clock_div_1);
+
+       /* Hardware Initialization */
+       LEDs_Init();
+       USB_Init();
+
+       /* Start the flush timer so that overflows occur rapidly to push received bytes to the USB interface */
+       TCCR0B = (1 << CS02);
+}
+
+/** Event handler for the library USB Connection event. */
+void EVENT_USB_Device_Connect(void)
+{
+       LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
+}
+
+/** Event handler for the library USB Disconnection event. */
+void EVENT_USB_Device_Disconnect(void)
+{
+       LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
+}
+
+/** Event handler for the library USB Configuration Changed event. */
+void EVENT_USB_Device_ConfigurationChanged(void)
+{
+       bool ConfigSuccess = true;
+
+       ConfigSuccess &= CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface);
+
+       LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
+}
+
+/** Event handler for the library USB Control Request reception event. */
+void EVENT_USB_Device_ControlRequest(void)
+{
+       CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
+}
+
+/** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
+ *  for later transmission to the host.
+ */
+ISR(USART1_RX_vect, ISR_BLOCK)
+{
+       uint8_t ReceivedByte = UDR1;
+
+       if (USB_DeviceState == DEVICE_STATE_Configured)
+         RingBuffer_Insert(&USARTtoUSB_Buffer, ReceivedByte);
+}
+
+/** Event handler for the CDC Class driver Line Encoding Changed event.
+ *
+ *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
+ */
+void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
+{
+       uint8_t ConfigMask = 0;
+
+       switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
+       {
+               case CDC_PARITY_Odd:
+                       ConfigMask = ((1 << UPM11) | (1 << UPM10));
+                       break;
+               case CDC_PARITY_Even:
+                       ConfigMask = (1 << UPM11);
+                       break;
+       }
+
+       if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
+         ConfigMask |= (1 << USBS1);
+
+       switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
+       {
+               case 6:
+                       ConfigMask |= (1 << UCSZ10);
+                       break;
+               case 7:
+                       ConfigMask |= (1 << UCSZ11);
+                       break;
+               case 8:
+                       ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
+                       break;
+       }
+
+       /* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */
+       UCSR1B = 0;
+       UCSR1A = 0;
+       UCSR1C = 0;
+
+       /* Set the new baud rate before configuring the USART */
+       UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
+
+       /* Reconfigure the USART in double speed mode for a wider baud rate range at the expense of accuracy */
+       UCSR1C = ConfigMask;
+       UCSR1A = (1 << U2X1);
+       UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
+}
+