From e018ceebed74b8223482bc9d1ed0b31c938381da Mon Sep 17 00:00:00 2001 From: Yuval Adam Date: Mon, 29 Oct 2012 23:04:19 +0200 Subject: New example files --- .../ek-lm4f120xl/usb_dev_serial/usb_dev_serial.c | 1223 ++++++++++++++++++++ 1 file changed, 1223 insertions(+) create mode 100644 boards/ek-lm4f120xl/usb_dev_serial/usb_dev_serial.c (limited to 'boards/ek-lm4f120xl/usb_dev_serial/usb_dev_serial.c') diff --git a/boards/ek-lm4f120xl/usb_dev_serial/usb_dev_serial.c b/boards/ek-lm4f120xl/usb_dev_serial/usb_dev_serial.c new file mode 100644 index 0000000..a8661a0 --- /dev/null +++ b/boards/ek-lm4f120xl/usb_dev_serial/usb_dev_serial.c @@ -0,0 +1,1223 @@ +//***************************************************************************** +// +// usb_dev_serial.c - Main routines for the USB CDC serial example. +// +// Copyright (c) 2012 Texas Instruments Incorporated. All rights reserved. +// Software License Agreement +// +// Texas Instruments (TI) is supplying this software for use solely and +// exclusively on TI's microcontroller products. The software is owned by +// TI and/or its suppliers, and is protected under applicable copyright +// laws. You may not combine this software with "viral" open-source +// software in order to form a larger program. +// +// THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS. +// NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT +// NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. TI SHALL NOT, UNDER ANY +// CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL +// DAMAGES, FOR ANY REASON WHATSOEVER. +// +// This is part of revision 9453 of the EK-LM4F120XL Firmware Package. +// +//***************************************************************************** + +#include "inc/hw_ints.h" +#include "inc/hw_memmap.h" +#include "inc/hw_types.h" +#include "inc/hw_gpio.h" +#include "inc/hw_uart.h" +#include "inc/hw_sysctl.h" +#include "driverlib/debug.h" +#include "driverlib/fpu.h" +#include "driverlib/gpio.h" +#include "driverlib/pin_map.h" +#include "driverlib/interrupt.h" +#include "driverlib/sysctl.h" +#include "driverlib/systick.h" +#include "driverlib/timer.h" +#include "driverlib/uart.h" +#include "driverlib/usb.h" +#include "driverlib/rom.h" +#include "usblib/usblib.h" +#include "usblib/usbcdc.h" +#include "usblib/usb-ids.h" +#include "usblib/device/usbdevice.h" +#include "usblib/device/usbdcdc.h" +#include "utils/ustdlib.h" +#include "usb_serial_structs.h" +#include "utils/uartstdio.h" + +//***************************************************************************** +// +//! \addtogroup example_list +//!

USB Serial Device (usb_dev_serial)

+//! +//! This example application turns the evaluation kit into a virtual serial +//! port when connected to the USB host system. The application supports the +//! USB Communication Device Class, Abstract Control Model to redirect UART0 +//! traffic to and from the USB host system. +//! +//! Assuming you installed StellarisWare in the default directory, a +//! driver information (INF) file for use with Windows XP, Windows Vista and +//! Windows7 can be found in C:/StellarisWare/windows_drivers. For Windows +//! 2000, the required INF file is in C:/StellarisWare/windows_drivers/win2K. +// +//***************************************************************************** + +//***************************************************************************** +// +// Note: +// +// This example is intended to run on Stellaris evaluation kit hardware +// where the UARTs are wired solely for TX and RX, and do not have GPIOs +// connected to act as handshake signals. As a result, this example mimics +// the case where communication is always possible. It reports DSR, DCD +// and CTS as high to ensure that the USB host recognizes that data can be +// sent and merely ignores the host's requested DTR and RTS states. "TODO" +// comments in the code indicate where code would be required to add support +// for real handshakes. +// +//***************************************************************************** + +//***************************************************************************** +// +// Configuration and tuning parameters. +// +//***************************************************************************** + +//***************************************************************************** +// +// The system tick rate expressed both as ticks per second and a millisecond +// period. +// +//***************************************************************************** +#define SYSTICKS_PER_SECOND 100 +#define SYSTICK_PERIOD_MS (1000 / SYSTICKS_PER_SECOND) + +//***************************************************************************** +// +// Variables tracking transmit and receive counts. +// +//***************************************************************************** +volatile unsigned long g_ulUARTTxCount = 0; +volatile unsigned long g_ulUARTRxCount = 0; +#ifdef DEBUG +unsigned long g_ulUARTRxErrors = 0; +#endif + +//***************************************************************************** +// +// The base address, peripheral ID and interrupt ID of the UART that is to +// be redirected. +// +//***************************************************************************** + +//***************************************************************************** +// +// Defines required to redirect UART0 via USB. +// +//***************************************************************************** +#define USB_UART_BASE UART0_BASE +#define USB_UART_PERIPH SYSCTL_PERIPH_UART0 +#define USB_UART_INT INT_UART0 + +//***************************************************************************** +// +// Default line coding settings for the redirected UART. +// +//***************************************************************************** +#define DEFAULT_BIT_RATE 115200 +#define DEFAULT_UART_CONFIG (UART_CONFIG_WLEN_8 | UART_CONFIG_PAR_NONE | \ + UART_CONFIG_STOP_ONE) + +//***************************************************************************** +// +// GPIO peripherals and pins muxed with the redirected UART. These will depend +// upon the IC in use and the UART selected in USB_UART_BASE. Be careful that +// these settings all agree with the hardware you are using. +// +//***************************************************************************** + +//***************************************************************************** +// +// Defines required to redirect UART0 via USB. +// +//***************************************************************************** +#define TX_GPIO_BASE GPIO_PORTA_BASE +#define TX_GPIO_PERIPH SYSCTL_PERIPH_GPIOA +#define TX_GPIO_PIN GPIO_PIN_1 + +#define RX_GPIO_BASE GPIO_PORTA_BASE +#define RX_GPIO_PERIPH SYSCTL_PERIPH_GPIOA +#define RX_GPIO_PIN GPIO_PIN_0 + +//***************************************************************************** +// +// Flag indicating whether or not we are currently sending a Break condition. +// +//***************************************************************************** +static tBoolean g_bSendingBreak = false; + +//***************************************************************************** +// +// Global system tick counter +// +//***************************************************************************** +volatile unsigned long g_ulSysTickCount = 0; + +//***************************************************************************** +// +// Flags used to pass commands from interrupt context to the main loop. +// +//***************************************************************************** +#define COMMAND_PACKET_RECEIVED 0x00000001 +#define COMMAND_STATUS_UPDATE 0x00000002 + +volatile unsigned long g_ulFlags = 0; +char *g_pcStatus; + +//***************************************************************************** +// +// Global flag indicating that a USB configuration has been set. +// +//***************************************************************************** +static volatile tBoolean g_bUSBConfigured = false; + +//***************************************************************************** +// +// Internal function prototypes. +// +//***************************************************************************** +static void USBUARTPrimeTransmit(unsigned long ulBase); +static void CheckForSerialStateChange(const tUSBDCDCDevice *psDevice, long lErrors); +static void SetControlLineState(unsigned short usState); +static tBoolean SetLineCoding(tLineCoding *psLineCoding); +static void GetLineCoding(tLineCoding *psLineCoding); +static void SendBreak(tBoolean bSend); + +//***************************************************************************** +// +// The error routine that is called if the driver library encounters an error. +// +//***************************************************************************** +#ifdef DEBUG +void +__error__(char *pcFilename, unsigned long ulLine) +{ + while(1) + { + } +} +#endif + +//***************************************************************************** +// +// This function is called whenever serial data is received from the UART. +// It is passed the accumulated error flags from each character received in +// this interrupt and determines from them whether or not an interrupt +// notification to the host is required. +// +// If a notification is required and the control interrupt endpoint is idle, +// we send the notification immediately. If the endpoint is not idle, we +// accumulate the errors in a global variable which will be checked on +// completion of the previous notification and used to send a second one +// if necessary. +// +//***************************************************************************** +static void +CheckForSerialStateChange(const tUSBDCDCDevice *psDevice, long lErrors) +{ + unsigned short usSerialState; + + // + // Clear our USB serial state. Since we are faking the handshakes, always + // set the TXCARRIER (DSR) and RXCARRIER (DCD) bits. + // + usSerialState = USB_CDC_SERIAL_STATE_TXCARRIER | + USB_CDC_SERIAL_STATE_RXCARRIER; + + // + // Are any error bits set? + // + if(lErrors) + { + // + // At least one error is being notified so translate from our hardware + // error bits into the correct state markers for the USB notification. + // + if(lErrors & UART_DR_OE) + { + usSerialState |= USB_CDC_SERIAL_STATE_OVERRUN; + } + + if(lErrors & UART_DR_PE) + { + usSerialState |= USB_CDC_SERIAL_STATE_PARITY; + } + + if(lErrors & UART_DR_FE) + { + usSerialState |= USB_CDC_SERIAL_STATE_FRAMING; + } + + if(lErrors & UART_DR_BE) + { + usSerialState |= USB_CDC_SERIAL_STATE_BREAK; + } + + // Call the CDC driver to notify the state change. + USBDCDCSerialStateChange((void *)psDevice, usSerialState); + } +} + +//***************************************************************************** +// +// Read as many characters from the UART FIFO as we can and move them into +// the CDC transmit buffer. +// +// \return Returns UART error flags read during data reception. +// +//***************************************************************************** +static long +ReadUARTData(void) +{ + long lChar, lErrors; + unsigned char ucChar; + unsigned long ulSpace; + + // + // Clear our error indicator. + // + lErrors = 0; + + // + // How much space do we have in the buffer? + // + ulSpace = USBBufferSpaceAvailable((tUSBBuffer *)&g_sTxBuffer); + + // + // Read data from the UART FIFO until there is none left or we run + // out of space in our receive buffer. + // + while(ulSpace && ROM_UARTCharsAvail(USB_UART_BASE)) + { + // + // Read a character from the UART FIFO into the ring buffer if no + // errors are reported. + // + lChar = ROM_UARTCharGetNonBlocking(USB_UART_BASE); + + // + // If the character did not contain any error notifications, + // copy it to the output buffer. + // + if(!(lChar & ~0xFF)) + { + ucChar = (unsigned char)(lChar & 0xFF); + USBBufferWrite((tUSBBuffer *)&g_sTxBuffer, + (unsigned char *)&ucChar, 1); + + // + // Decrement the number of bytes we know the buffer can accept. + // + ulSpace--; + } + else + { +#ifdef DEBUG + // + // Increment our receive error counter. + // + g_ulUARTRxErrors++; +#endif + // + // Update our error accumulator. + // + lErrors |= lChar; + } + + // + // Update our count of bytes received via the UART. + // + g_ulUARTRxCount++; + } + + // + // Pass back the accumulated error indicators. + // + return(lErrors); +} + +//***************************************************************************** +// +// Take as many bytes from the transmit buffer as we have space for and move +// them into the USB UART's transmit FIFO. +// +//***************************************************************************** +static void +USBUARTPrimeTransmit(unsigned long ulBase) +{ + unsigned long ulRead; + unsigned char ucChar; + + // + // If we are currently sending a break condition, don't receive any + // more data. We will resume transmission once the break is turned off. + // + if(g_bSendingBreak) + { + return; + } + + // + // If there is space in the UART FIFO, try to read some characters + // from the receive buffer to fill it again. + // + while(ROM_UARTSpaceAvail(ulBase)) + { + // + // Get a character from the buffer. + // + ulRead = USBBufferRead((tUSBBuffer *)&g_sRxBuffer, &ucChar, 1); + + // + // Did we get a character? + // + if(ulRead) + { + // + // Place the character in the UART transmit FIFO. + // + ROM_UARTCharPutNonBlocking(ulBase, ucChar); + + // + // Update our count of bytes transmitted via the UART. + // + g_ulUARTTxCount++; + } + else + { + // + // We ran out of characters so exit the function. + // + return; + } + } +} + +//***************************************************************************** +// +// Interrupt handler for the system tick counter. +// +//***************************************************************************** +void +SysTickIntHandler(void) +{ + // + // Update our system time. + // + g_ulSysTickCount++; +} + +//***************************************************************************** +// +// Interrupt handler for the UART which we are redirecting via USB. +// +//***************************************************************************** +void +USBUARTIntHandler(void) +{ + unsigned long ulInts; + long lErrors; + + // + // Get and clear the current interrupt source(s) + // + ulInts = ROM_UARTIntStatus(USB_UART_BASE, true); + ROM_UARTIntClear(USB_UART_BASE, ulInts); + + // + // Are we being interrupted because the TX FIFO has space available? + // + if(ulInts & UART_INT_TX) + { + // + // Move as many bytes as we can into the transmit FIFO. + // + USBUARTPrimeTransmit(USB_UART_BASE); + + // + // If the output buffer is empty, turn off the transmit interrupt. + // + if(!USBBufferDataAvailable(&g_sRxBuffer)) + { + ROM_UARTIntDisable(USB_UART_BASE, UART_INT_TX); + } + } + + // + // Handle receive interrupts. + // + if(ulInts & (UART_INT_RX | UART_INT_RT)) + { + // + // Read the UART's characters into the buffer. + // + lErrors = ReadUARTData(); + + // + // Check to see if we need to notify the host of any errors we just + // detected. + // + CheckForSerialStateChange(&g_sCDCDevice, lErrors); + } +} + +//***************************************************************************** +// +// Set the state of the RS232 RTS and DTR signals. +// +//***************************************************************************** +static void +SetControlLineState(unsigned short usState) +{ + // + // TODO: If configured with GPIOs controlling the handshake lines, + // set them appropriately depending upon the flags passed in the wValue + // field of the request structure passed. + // +} + +//***************************************************************************** +// +// Set the communication parameters to use on the UART. +// +//***************************************************************************** +static tBoolean +SetLineCoding(tLineCoding *psLineCoding) +{ + unsigned long ulConfig; + tBoolean bRetcode; + + // + // Assume everything is OK until we detect any problem. + // + bRetcode = true; + + // + // Word length. For invalid values, the default is to set 8 bits per + // character and return an error. + // + switch(psLineCoding->ucDatabits) + { + case 5: + { + ulConfig = UART_CONFIG_WLEN_5; + break; + } + + case 6: + { + ulConfig = UART_CONFIG_WLEN_6; + break; + } + + case 7: + { + ulConfig = UART_CONFIG_WLEN_7; + break; + } + + case 8: + { + ulConfig = UART_CONFIG_WLEN_8; + break; + } + + default: + { + ulConfig = UART_CONFIG_WLEN_8; + bRetcode = false; + break; + } + } + + // + // Parity. For any invalid values, we set no parity and return an error. + // + switch(psLineCoding->ucParity) + { + case USB_CDC_PARITY_NONE: + { + ulConfig |= UART_CONFIG_PAR_NONE; + break; + } + + case USB_CDC_PARITY_ODD: + { + ulConfig |= UART_CONFIG_PAR_ODD; + break; + } + + case USB_CDC_PARITY_EVEN: + { + ulConfig |= UART_CONFIG_PAR_EVEN; + break; + } + + case USB_CDC_PARITY_MARK: + { + ulConfig |= UART_CONFIG_PAR_ONE; + break; + } + + case USB_CDC_PARITY_SPACE: + { + ulConfig |= UART_CONFIG_PAR_ZERO; + break; + } + + default: + { + ulConfig |= UART_CONFIG_PAR_NONE; + bRetcode = false; + break; + } + } + + // + // Stop bits. Our hardware only supports 1 or 2 stop bits whereas CDC + // allows the host to select 1.5 stop bits. If passed 1.5 (or any other + // invalid or unsupported value of ucStop, we set up for 1 stop bit but + // return an error in case the caller needs to Stall or otherwise report + // this back to the host. + // + switch(psLineCoding->ucStop) + { + // + // One stop bit requested. + // + case USB_CDC_STOP_BITS_1: + { + ulConfig |= UART_CONFIG_STOP_ONE; + break; + } + + // + // Two stop bits requested. + // + case USB_CDC_STOP_BITS_2: + { + ulConfig |= UART_CONFIG_STOP_TWO; + break; + } + + // + // Other cases are either invalid values of ucStop or values that we + // cannot support so set 1 stop bit but return an error. + // + default: + { + ulConfig = UART_CONFIG_STOP_ONE; + bRetcode |= false; + break; + } + } + + // + // Set the UART mode appropriately. + // + ROM_UARTConfigSetExpClk(USB_UART_BASE, ROM_SysCtlClockGet(), + psLineCoding->ulRate, ulConfig); + + // + // Let the caller know if we had a problem or not. + // + return(bRetcode); +} + +//***************************************************************************** +// +// Get the communication parameters in use on the UART. +// +//***************************************************************************** +static void +GetLineCoding(tLineCoding *psLineCoding) +{ + unsigned long ulConfig; + unsigned long ulRate; + + // + // Get the current line coding set in the UART. + // + ROM_UARTConfigGetExpClk(USB_UART_BASE, ROM_SysCtlClockGet(), &ulRate, + &ulConfig); + psLineCoding->ulRate = ulRate; + + // + // Translate the configuration word length field into the format expected + // by the host. + // + switch(ulConfig & UART_CONFIG_WLEN_MASK) + { + case UART_CONFIG_WLEN_8: + { + psLineCoding->ucDatabits = 8; + break; + } + + case UART_CONFIG_WLEN_7: + { + psLineCoding->ucDatabits = 7; + break; + } + + case UART_CONFIG_WLEN_6: + { + psLineCoding->ucDatabits = 6; + break; + } + + case UART_CONFIG_WLEN_5: + { + psLineCoding->ucDatabits = 5; + break; + } + } + + // + // Translate the configuration parity field into the format expected + // by the host. + // + switch(ulConfig & UART_CONFIG_PAR_MASK) + { + case UART_CONFIG_PAR_NONE: + { + psLineCoding->ucParity = USB_CDC_PARITY_NONE; + break; + } + + case UART_CONFIG_PAR_ODD: + { + psLineCoding->ucParity = USB_CDC_PARITY_ODD; + break; + } + + case UART_CONFIG_PAR_EVEN: + { + psLineCoding->ucParity = USB_CDC_PARITY_EVEN; + break; + } + + case UART_CONFIG_PAR_ONE: + { + psLineCoding->ucParity = USB_CDC_PARITY_MARK; + break; + } + + case UART_CONFIG_PAR_ZERO: + { + psLineCoding->ucParity = USB_CDC_PARITY_SPACE; + break; + } + } + + // + // Translate the configuration stop bits field into the format expected + // by the host. + // + switch(ulConfig & UART_CONFIG_STOP_MASK) + { + case UART_CONFIG_STOP_ONE: + { + psLineCoding->ucStop = USB_CDC_STOP_BITS_1; + break; + } + + case UART_CONFIG_STOP_TWO: + { + psLineCoding->ucStop = USB_CDC_STOP_BITS_2; + break; + } + } +} + +//***************************************************************************** +// +// This function sets or clears a break condition on the redirected UART RX +// line. A break is started when the function is called with \e bSend set to +// \b true and persists until the function is called again with \e bSend set +// to \b false. +// +//***************************************************************************** +static void +SendBreak(tBoolean bSend) +{ + // + // Are we being asked to start or stop the break condition? + // + if(!bSend) + { + // + // Remove the break condition on the line. + // + ROM_UARTBreakCtl(USB_UART_BASE, false); + g_bSendingBreak = false; + } + else + { + // + // Start sending a break condition on the line. + // + ROM_UARTBreakCtl(USB_UART_BASE, true); + g_bSendingBreak = true; + } +} + +//***************************************************************************** +// +// Handles CDC driver notifications related to control and setup of the device. +// +// \param pvCBData is the client-supplied callback pointer for this channel. +// \param ulEvent identifies the event we are being notified about. +// \param ulMsgValue is an event-specific value. +// \param pvMsgData is an event-specific pointer. +// +// This function is called by the CDC driver to perform control-related +// operations on behalf of the USB host. These functions include setting +// and querying the serial communication parameters, setting handshake line +// states and sending break conditions. +// +// \return The return value is event-specific. +// +//***************************************************************************** +unsigned long +ControlHandler(void *pvCBData, unsigned long ulEvent, + unsigned long ulMsgValue, void *pvMsgData) +{ + unsigned long ulIntsOff; + + // + // Which event are we being asked to process? + // + switch(ulEvent) + { + // + // We are connected to a host and communication is now possible. + // + case USB_EVENT_CONNECTED: + g_bUSBConfigured = true; + + // + // Flush our buffers. + // + USBBufferFlush(&g_sTxBuffer); + USBBufferFlush(&g_sRxBuffer); + + // + // Tell the main loop to update the display. + // + ulIntsOff = ROM_IntMasterDisable(); + g_pcStatus = "Connected"; + g_ulFlags |= COMMAND_STATUS_UPDATE; + if(!ulIntsOff) + { + ROM_IntMasterEnable(); + } + break; + + // + // The host has disconnected. + // + case USB_EVENT_DISCONNECTED: + g_bUSBConfigured = false; + ulIntsOff = ROM_IntMasterDisable(); + g_pcStatus = "Disconnected"; + g_ulFlags |= COMMAND_STATUS_UPDATE; + if(!ulIntsOff) + { + ROM_IntMasterEnable(); + } + break; + + // + // Return the current serial communication parameters. + // + case USBD_CDC_EVENT_GET_LINE_CODING: + GetLineCoding(pvMsgData); + break; + + // + // Set the current serial communication parameters. + // + case USBD_CDC_EVENT_SET_LINE_CODING: + SetLineCoding(pvMsgData); + break; + + // + // Set the current serial communication parameters. + // + case USBD_CDC_EVENT_SET_CONTROL_LINE_STATE: + SetControlLineState((unsigned short)ulMsgValue); + break; + + // + // Send a break condition on the serial line. + // + case USBD_CDC_EVENT_SEND_BREAK: + SendBreak(true); + break; + + // + // Clear the break condition on the serial line. + // + case USBD_CDC_EVENT_CLEAR_BREAK: + SendBreak(false); + break; + + // + // Ignore SUSPEND and RESUME for now. + // + case USB_EVENT_SUSPEND: + case USB_EVENT_RESUME: + break; + + // + // We don't expect to receive any other events. Ignore any that show + // up in a release build or hang in a debug build. + // + default: +#ifdef DEBUG + while(1); +#else + break; +#endif + + } + + return(0); +} + +//***************************************************************************** +// +// Handles CDC driver notifications related to the transmit channel (data to +// the USB host). +// +// \param ulCBData is the client-supplied callback pointer for this channel. +// \param ulEvent identifies the event we are being notified about. +// \param ulMsgValue is an event-specific value. +// \param pvMsgData is an event-specific pointer. +// +// This function is called by the CDC driver to notify us of any events +// related to operation of the transmit data channel (the IN channel carrying +// data to the USB host). +// +// \return The return value is event-specific. +// +//***************************************************************************** +unsigned long +TxHandler(void *pvCBData, unsigned long ulEvent, unsigned long ulMsgValue, + void *pvMsgData) +{ + // + // Which event have we been sent? + // + switch(ulEvent) + { + case USB_EVENT_TX_COMPLETE: + // + // Since we are using the USBBuffer, we don't need to do anything + // here. + // + break; + + // + // We don't expect to receive any other events. Ignore any that show + // up in a release build or hang in a debug build. + // + default: +#ifdef DEBUG + while(1); +#else + break; +#endif + + } + return(0); +} + +//***************************************************************************** +// +// Handles CDC driver notifications related to the receive channel (data from +// the USB host). +// +// \param ulCBData is the client-supplied callback data value for this channel. +// \param ulEvent identifies the event we are being notified about. +// \param ulMsgValue is an event-specific value. +// \param pvMsgData is an event-specific pointer. +// +// This function is called by the CDC driver to notify us of any events +// related to operation of the receive data channel (the OUT channel carrying +// data from the USB host). +// +// \return The return value is event-specific. +// +//***************************************************************************** +unsigned long +RxHandler(void *pvCBData, unsigned long ulEvent, unsigned long ulMsgValue, + void *pvMsgData) +{ + unsigned long ulCount; + + // + // Which event are we being sent? + // + switch(ulEvent) + { + // + // A new packet has been received. + // + case USB_EVENT_RX_AVAILABLE: + { + // + // Feed some characters into the UART TX FIFO and enable the + // interrupt so we are told when there is more space. + // + USBUARTPrimeTransmit(USB_UART_BASE); + ROM_UARTIntEnable(USB_UART_BASE, UART_INT_TX); + break; + } + + // + // We are being asked how much unprocessed data we have still to + // process. We return 0 if the UART is currently idle or 1 if it is + // in the process of transmitting something. The actual number of + // bytes in the UART FIFO is not important here, merely whether or + // not everything previously sent to us has been transmitted. + // + case USB_EVENT_DATA_REMAINING: + { + // + // Get the number of bytes in the buffer and add 1 if some data + // still has to clear the transmitter. + // + ulCount = ROM_UARTBusy(USB_UART_BASE) ? 1 : 0; + return(ulCount); + } + + // + // We are being asked to provide a buffer into which the next packet + // can be read. We do not support this mode of receiving data so let + // the driver know by returning 0. The CDC driver should not be sending + // this message but this is included just for illustration and + // completeness. + // + case USB_EVENT_REQUEST_BUFFER: + { + return(0); + } + + // + // We don't expect to receive any other events. Ignore any that show + // up in a release build or hang in a debug build. + // + default: +#ifdef DEBUG + while(1); +#else + break; +#endif + } + + return(0); +} + +//***************************************************************************** +// +// This is the main application entry function. +// +//***************************************************************************** +int +main(void) +{ + unsigned long ulTxCount; + unsigned long ulRxCount; + unsigned long ulLoop; + + // + // Enable lazy stacking for interrupt handlers. This allows floating-point + // instructions to be used within interrupt handlers, but at the expense of + // extra stack usage. + // + ROM_FPULazyStackingEnable(); + + // + // Set the clocking to run from the PLL at 50MHz + // + ROM_SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_PLL | SYSCTL_OSC_MAIN | + SYSCTL_XTAL_16MHZ); + + // + // Configure the required pins for USB operation. + // + ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD); + ROM_GPIOPinTypeUSBAnalog(GPIO_PORTD_BASE, GPIO_PIN_5 | GPIO_PIN_4); + + // + // Enable the GPIO port that is used for the on-board LED. + // + ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF); + + // + // Enable the GPIO pins for the LED (PF2 & PF3). + // + ROM_GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_3|GPIO_PIN_2); + + // + // Not configured initially. + // + g_bUSBConfigured = false; + + // + // Enable the UART that we will be redirecting. + // + ROM_SysCtlPeripheralEnable(USB_UART_PERIPH); + + // + // Enable and configure the UART RX and TX pins + // + ROM_SysCtlPeripheralEnable(TX_GPIO_PERIPH); + ROM_SysCtlPeripheralEnable(RX_GPIO_PERIPH); + ROM_GPIOPinTypeUART(TX_GPIO_BASE, TX_GPIO_PIN); + ROM_GPIOPinTypeUART(RX_GPIO_BASE, RX_GPIO_PIN); + + // + // TODO: Add code to configure handshake GPIOs if required. + // + + // + // Set the default UART configuration. + // + ROM_UARTConfigSetExpClk(USB_UART_BASE, ROM_SysCtlClockGet(), + DEFAULT_BIT_RATE, DEFAULT_UART_CONFIG); + ROM_UARTFIFOLevelSet(USB_UART_BASE, UART_FIFO_TX4_8, UART_FIFO_RX4_8); + + // + // Configure and enable UART interrupts. + // + ROM_UARTIntClear(USB_UART_BASE, ROM_UARTIntStatus(USB_UART_BASE, false)); + ROM_UARTIntEnable(USB_UART_BASE, (UART_INT_OE | UART_INT_BE | UART_INT_PE | + UART_INT_FE | UART_INT_RT | UART_INT_TX | UART_INT_RX)); + + // + // Enable the system tick. + // + ROM_SysTickPeriodSet(ROM_SysCtlClockGet() / SYSTICKS_PER_SECOND); + ROM_SysTickIntEnable(); + ROM_SysTickEnable(); + + // + // Initialize the transmit and receive buffers. + // + USBBufferInit((tUSBBuffer *)&g_sTxBuffer); + USBBufferInit((tUSBBuffer *)&g_sRxBuffer); + + // + // Set the USB stack mode to Device mode with VBUS monitoring. + // + USBStackModeSet(0, USB_MODE_DEVICE, 0); + + // + // Pass our device information to the USB library and place the device + // on the bus. + // + USBDCDCInit(0, (tUSBDCDCDevice *)&g_sCDCDevice); + + // + // Clear our local byte counters. + // + ulRxCount = 0; + ulTxCount = 0; + + // + // Enable interrupts now that the application is ready to start. + // + ROM_IntEnable(USB_UART_INT); + + // + // Main application loop. + // + while(1) + { + // + // Have we been asked to update the status display? + // + if(g_ulFlags & COMMAND_STATUS_UPDATE) + { + // + // Clear the command flag + // + ROM_IntMasterDisable(); + g_ulFlags &= ~COMMAND_STATUS_UPDATE; + ROM_IntMasterEnable(); + } + + // + // Has there been any transmit traffic since we last checked? + // + if(ulTxCount != g_ulUARTTxCount) + { + // + // Turn on the Green LED. + // + GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_3, GPIO_PIN_3); + + // + // Delay for a bit. + // + for(ulLoop = 0; ulLoop < 150000; ulLoop++) + { + } + + // + // Turn off the Green LED. + // + GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_3, 0); + + // + // Take a snapshot of the latest transmit count. + // + ulTxCount = g_ulUARTTxCount; + } + + // + // Has there been any receive traffic since we last checked? + // + if(ulRxCount != g_ulUARTRxCount) + { + // + // Turn on the Blue LED. + // + GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_2, GPIO_PIN_2); + + // + // Delay for a bit. + // + for(ulLoop = 0; ulLoop < 150000; ulLoop++) + { + } + + // + // Turn off the Blue LED. + // + GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_2, 0); + + // + // Take a snapshot of the latest receive count. + // + ulRxCount = g_ulUARTRxCount; + + } + } +} -- cgit v1.3.1