X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/1be3436e895c9937dcd4ebbec33ea199f3e26db2..d4b45e8502a27c0f5ad3e26eabd2b30e84c20bac:/Projects/USBtoSerial/USBtoSerial.c?ds=sidebyside diff --git a/Projects/USBtoSerial/USBtoSerial.c b/Projects/USBtoSerial/USBtoSerial.c index 845c2a51c..194f6b084 100644 --- a/Projects/USBtoSerial/USBtoSerial.c +++ b/Projects/USBtoSerial/USBtoSerial.c @@ -1,21 +1,21 @@ /* LUFA Library - Copyright (C) Dean Camera, 2010. - + Copyright (C) Dean Camera, 2012. + dean [at] fourwalledcubicle [dot] com - www.fourwalledcubicle.com + www.lufa-lib.org */ /* - Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com) + Copyright 2012 Dean Camera (dean [at] fourwalledcubicle [dot] com) - Permission to use, copy, modify, distribute, and sell this + 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 + 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 + 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 @@ -31,16 +31,22 @@ /** \file * * Main source file for the USBtoSerial project. This file contains the main tasks of - * the demo and is responsible for the initial application hardware configuration. + * 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. */ -RingBuff_t USBtoUSART_Buffer; +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. */ -RingBuff_t USARTtoUSB_Buffer; +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 @@ -48,7 +54,7 @@ RingBuff_t USARTtoUSB_Buffer; */ USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface = { - .Config = + .Config = { .ControlInterfaceNumber = 0, @@ -66,41 +72,58 @@ USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface = }, }; + /** 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); - RingBuffer_InitBuffer(&USARTtoUSB_Buffer); + + 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 (;;) { - /* Read bytes from the USB OUT endpoint into the USART transmit buffer */ - int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface); - if (!(ReceivedByte < 0) && !(RingBuffer_IsFull(&USBtoUSART_Buffer))) - RingBuffer_Insert(&USBtoUSART_Buffer, ReceivedByte); - + /* 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 */ - RingBuff_Count_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer); - if ((TIFR0 & (1 << TOV0)) || (BufferCount > 200)) + 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--) - CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_Remove(&USARTtoUSB_Buffer)); + { + /* 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_TxByte(RingBuffer_Remove(&USBtoUSART_Buffer)); - + Serial_SendByte(RingBuffer_Remove(&USBtoUSART_Buffer)); + CDC_Device_USBTask(&VirtualSerial_CDC_Interface); USB_USBTask(); } @@ -146,8 +169,8 @@ void EVENT_USB_Device_ConfigurationChanged(void) LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR); } -/** Event handler for the library USB Unhandled Control Request event. */ -void EVENT_USB_Device_UnhandledControlRequest(void) +/** Event handler for the library USB Control Request reception event. */ +void EVENT_USB_Device_ControlRequest(void) { CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface); } @@ -174,10 +197,10 @@ void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCI switch (CDCInterfaceInfo->State.LineEncoding.ParityType) { case CDC_PARITY_Odd: - ConfigMask = ((1 << UPM11) | (1 << UPM10)); + ConfigMask = ((1 << UPM11) | (1 << UPM10)); break; case CDC_PARITY_Even: - ConfigMask = (1 << UPM11); + ConfigMask = (1 << UPM11); break; } @@ -204,9 +227,10 @@ void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCI /* 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)); } +