diff options
Diffstat (limited to 'lib/lufa/Projects/USBtoSerial/USBtoSerial.c')
| -rw-r--r-- | lib/lufa/Projects/USBtoSerial/USBtoSerial.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/lib/lufa/Projects/USBtoSerial/USBtoSerial.c b/lib/lufa/Projects/USBtoSerial/USBtoSerial.c new file mode 100644 index 000000000..47a84a4ad --- /dev/null +++ b/lib/lufa/Projects/USBtoSerial/USBtoSerial.c @@ -0,0 +1,254 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2017. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2017 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 disclaims 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 = INTERFACE_ID_CDC_CCI, + .DataINEndpoint = + { + .Address = CDC_TX_EPADDR, + .Size = CDC_TXRX_EPSIZE, + .Banks = 1, + }, + .DataOUTEndpoint = + { + .Address = CDC_RX_EPADDR, + .Size = CDC_TXRX_EPSIZE, + .Banks = 1, + }, + .NotificationEndpoint = + { + .Address = CDC_NOTIFICATION_EPADDR, + .Size = CDC_NOTIFICATION_EPSIZE, + .Banks = 1, + }, + }, + }; + + +/** 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); + GlobalInterruptEnable(); + + 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); + + /* Store received byte into the USART transmit buffer */ + if (!(ReceivedByte < 0)) + RingBuffer_Insert(&USBtoUSART_Buffer, ReceivedByte); + } + + uint16_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer); + if (BufferCount) + { + Endpoint_SelectEndpoint(VirtualSerial_CDC_Interface.Config.DataINEndpoint.Address); + + /* Check if a packet is already enqueued to the host - if so, we shouldn't try to send more data + * until it completes as there is a chance nothing is listening and a lengthy timeout could occur */ + if (Endpoint_IsINReady()) + { + /* Never send more than one bank size less one byte to the host at a time, so that we don't block + * while a Zero Length Packet (ZLP) to terminate the transfer is sent if the host isn't listening */ + uint8_t BytesToSend = MIN(BufferCount, (CDC_TXRX_EPSIZE - 1)); + + /* Read bytes from the USART receive buffer into the USB IN endpoint */ + while (BytesToSend--) + { + /* 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 transmit buffer space is available */ + if (Serial_IsSendReady() && !(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) +{ +#if (ARCH == ARCH_AVR8) + /* Disable watchdog if enabled by bootloader/fuses */ + MCUSR &= ~(1 << WDRF); + wdt_disable(); + + /* Disable clock division */ + clock_prescale_set(clock_div_1); +#endif + + /* Hardware Initialization */ + LEDs_Init(); + USB_Init(); +} + +/** 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_IsFull(&USARTtoUSB_Buffer))) + 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; + } + + /* Keep the TX line held high (idle) while the USART is reconfigured */ + PORTD |= (1 << 3); + + /* 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)); + + /* Release the TX line after the USART has been reconfigured */ + PORTD &= ~(1 << 3); +} + |