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/*
LPCUSB, an USB device driver for LPC microcontrollers
Copyright (C) 2006 Bertrik Sikken (bertrik@sikken.nl)
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. The name of the author may not be used to endorse or promote products
derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
Minimal implementation of a USB serial port, using the CDC class.
This example application simply echoes everything it receives right back
to the host.
Windows:
Extract the usbser.sys file from .cab file in C:\WINDOWS\Driver Cache\i386
and store it somewhere (C:\temp is a good place) along with the usbser.inf
file. Then plug in the LPC176x and direct windows to the usbser driver.
Windows then creates an extra COMx port that you can open in a terminal
program, like hyperterminal. [Note for FreeRTOS users - the required .inf
file is included in the project directory.]
Linux:
The device should be recognised automatically by the cdc_acm driver,
which creates a /dev/ttyACMx device file that acts just like a regular
serial port.
*/
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include <stdio.h>
#include <string.h>
#include "usbapi.h"
#include "usbdebug.h"
#include "usbstruct.h"
#include "LPC17xx.h"
#define usbMAX_SEND_BLOCK ( 20 / portTICK_RATE_MS )
#define usbBUFFER_LEN ( 20 )
#define INCREMENT_ECHO_BY 1
#define BAUD_RATE 115200
#define INT_IN_EP 0x81
#define BULK_OUT_EP 0x05
#define BULK_IN_EP 0x82
#define MAX_PACKET_SIZE 64
#define LE_WORD(x) ((x)&0xFF),((x)>>8)
// CDC definitions
#define CS_INTERFACE 0x24
#define CS_ENDPOINT 0x25
#define SET_LINE_CODING 0x20
#define GET_LINE_CODING 0x21
#define SET_CONTROL_LINE_STATE 0x22
// data structure for GET_LINE_CODING / SET_LINE_CODING class requests
typedef struct {
unsigned long dwDTERate;
unsigned char bCharFormat;
unsigned char bParityType;
unsigned char bDataBits;
} TLineCoding;
static TLineCoding LineCoding = {115200, 0, 0, 8};
static unsigned char abBulkBuf[64];
static unsigned char abClassReqData[8];
static xQueueHandle xRxedChars = NULL, xCharsForTx = NULL;
// forward declaration of interrupt handler
void USBIntHandler(void);
static const unsigned char abDescriptors[] = {
// device descriptor
0x12,
DESC_DEVICE,
LE_WORD(0x0101), // bcdUSB
0x02, // bDeviceClass
0x00, // bDeviceSubClass
0x00, // bDeviceProtocol
MAX_PACKET_SIZE0, // bMaxPacketSize
LE_WORD(0xFFFF), // idVendor
LE_WORD(0x0005), // idProduct
LE_WORD(0x0100), // bcdDevice
0x01, // iManufacturer
0x02, // iProduct
0x03, // iSerialNumber
0x01, // bNumConfigurations
// configuration descriptor
0x09,
DESC_CONFIGURATION,
LE_WORD(67), // wTotalLength
0x02, // bNumInterfaces
0x01, // bConfigurationValue
0x00, // iConfiguration
0xC0, // bmAttributes
0x32, // bMaxPower
// control class interface
0x09,
DESC_INTERFACE,
0x00, // bInterfaceNumber
0x00, // bAlternateSetting
0x01, // bNumEndPoints
0x02, // bInterfaceClass
0x02, // bInterfaceSubClass
0x01, // bInterfaceProtocol, linux requires value of 1 for the cdc_acm module
0x00, // iInterface
// header functional descriptor
0x05,
CS_INTERFACE,
0x00,
LE_WORD(0x0110),
// call management functional descriptor
0x05,
CS_INTERFACE,
0x01,
0x01, // bmCapabilities = device handles call management
0x01, // bDataInterface
// ACM functional descriptor
0x04,
CS_INTERFACE,
0x02,
0x02, // bmCapabilities
// union functional descriptor
0x05,
CS_INTERFACE,
0x06,
0x00, // bMasterInterface
0x01, // bSlaveInterface0
// notification EP
0x07,
DESC_ENDPOINT,
INT_IN_EP, // bEndpointAddress
0x03, // bmAttributes = intr
LE_WORD(8), // wMaxPacketSize
0x0A, // bInterval
// data class interface descriptor
0x09,
DESC_INTERFACE,
0x01, // bInterfaceNumber
0x00, // bAlternateSetting
0x02, // bNumEndPoints
0x0A, // bInterfaceClass = data
0x00, // bInterfaceSubClass
0x00, // bInterfaceProtocol
0x00, // iInterface
// data EP OUT
0x07,
DESC_ENDPOINT,
BULK_OUT_EP, // bEndpointAddress
0x02, // bmAttributes = bulk
LE_WORD(MAX_PACKET_SIZE), // wMaxPacketSize
0x00, // bInterval
// data EP in
0x07,
DESC_ENDPOINT,
BULK_IN_EP, // bEndpointAddress
0x02, // bmAttributes = bulk
LE_WORD(MAX_PACKET_SIZE), // wMaxPacketSize
0x00, // bInterval
// string descriptors
0x04,
DESC_STRING,
LE_WORD(0x0409),
0x0E,
DESC_STRING,
'L', 0, 'P', 0, 'C', 0, 'U', 0, 'S', 0, 'B', 0,
0x14,
DESC_STRING,
'U', 0, 'S', 0, 'B', 0, 'S', 0, 'e', 0, 'r', 0, 'i', 0, 'a', 0, 'l', 0,
0x12,
DESC_STRING,
'D', 0, 'E', 0, 'A', 0, 'D', 0, 'C', 0, '0', 0, 'D', 0, 'E', 0,
// terminating zero
0
};
/**
Local function to handle incoming bulk data
@param [in] bEP
@param [in] bEPStatus
*/
static void BulkOut(unsigned char bEP, unsigned char bEPStatus)
{
int i, iLen;
long lHigherPriorityTaskWoken = pdFALSE;
( void ) bEPStatus;
// get data from USB into intermediate buffer
iLen = USBHwEPRead(bEP, abBulkBuf, sizeof(abBulkBuf));
for (i = 0; i < iLen; i++) {
// put into queue
xQueueSendFromISR( xRxedChars, &( abBulkBuf[ i ] ), &lHigherPriorityTaskWoken );
}
portEND_SWITCHING_ISR( lHigherPriorityTaskWoken );
}
/**
Local function to handle outgoing bulk data
@param [in] bEP
@param [in] bEPStatus
*/
static void BulkIn(unsigned char bEP, unsigned char bEPStatus)
{
int i, iLen;
long lHigherPriorityTaskWoken = pdFALSE;
( void ) bEPStatus;
if (uxQueueMessagesWaitingFromISR( xCharsForTx ) == 0) {
// no more data, disable further NAK interrupts until next USB frame
USBHwNakIntEnable(0);
return;
}
// get bytes from transmit FIFO into intermediate buffer
for (i = 0; i < MAX_PACKET_SIZE; i++) {
if( xQueueReceiveFromISR( xCharsForTx, ( &abBulkBuf[i] ), &lHigherPriorityTaskWoken ) != pdPASS )
{
break;
}
}
iLen = i;
// send over USB
if (iLen > 0) {
USBHwEPWrite(bEP, abBulkBuf, iLen);
}
portEND_SWITCHING_ISR( lHigherPriorityTaskWoken );
}
/**
Local function to handle the USB-CDC class requests
@param [in] pSetup
@param [out] piLen
@param [out] ppbData
*/
static BOOL HandleClassRequest(TSetupPacket *pSetup, int *piLen, unsigned char **ppbData)
{
switch (pSetup->bRequest) {
// set line coding
case SET_LINE_CODING:
DBG("SET_LINE_CODING\n");
memcpy((unsigned char *)&LineCoding, *ppbData, 7);
*piLen = 7;
DBG("dwDTERate=%u, bCharFormat=%u, bParityType=%u, bDataBits=%u\n",
LineCoding.dwDTERate,
LineCoding.bCharFormat,
LineCoding.bParityType,
LineCoding.bDataBits);
break;
// get line coding
case GET_LINE_CODING:
DBG("GET_LINE_CODING\n");
*ppbData = (unsigned char *)&LineCoding;
*piLen = 7;
break;
// set control line state
case SET_CONTROL_LINE_STATE:
// bit0 = DTR, bit = RTS
DBG("SET_CONTROL_LINE_STATE %X\n", pSetup->wValue);
break;
default:
return FALSE;
}
return TRUE;
}
/**
Writes one character to VCOM port
@param [in] c character to write
@returns character written, or EOF if character could not be written
*/
int VCOM_putchar(int c)
{
char cc = ( char ) c;
if( xQueueSend( xCharsForTx, &cc, usbMAX_SEND_BLOCK ) == pdPASS )
{
return c;
}
else
{
return EOF;
}
}
/**
Reads one character from VCOM port
@returns character read, or EOF if character could not be read
*/
int VCOM_getchar(void)
{
unsigned char c;
/* Block the task until a character is available. */
xQueueReceive( xRxedChars, &c, portMAX_DELAY );
return c;
}
/**
Interrupt handler
Simply calls the USB ISR
*/
//void USBIntHandler(void)
void USB_IRQHandler(void)
{
USBHwISR();
}
static void USBFrameHandler(unsigned short wFrame)
{
( void ) wFrame;
if( uxQueueMessagesWaitingFromISR( xCharsForTx ) > 0 )
{
// data available, enable NAK interrupt on bulk in
USBHwNakIntEnable(INACK_BI);
}
}
void vUSBTask( void *pvParameters )
{
int c;
/* Just to prevent compiler warnings about the unused parameter. */
( void ) pvParameters;
DBG("Initialising USB stack\n");
xRxedChars = xQueueCreate( usbBUFFER_LEN, sizeof( char ) );
xCharsForTx = xQueueCreate( usbBUFFER_LEN, sizeof( char ) );
if( ( xRxedChars == NULL ) || ( xCharsForTx == NULL ) )
{
/* Not enough heap available to create the buffer queues, can't do
anything so just delete ourselves. */
vTaskDelete( NULL );
}
// initialise stack
USBInit();
// register descriptors
USBRegisterDescriptors(abDescriptors);
// register class request handler
USBRegisterRequestHandler(REQTYPE_TYPE_CLASS, HandleClassRequest, abClassReqData);
// register endpoint handlers
USBHwRegisterEPIntHandler(INT_IN_EP, NULL);
USBHwRegisterEPIntHandler(BULK_IN_EP, BulkIn);
USBHwRegisterEPIntHandler(BULK_OUT_EP, BulkOut);
// register frame handler
USBHwRegisterFrameHandler(USBFrameHandler);
// enable bulk-in interrupts on NAKs
USBHwNakIntEnable(INACK_BI);
DBG("Starting USB communication\n");
NVIC_SetPriority( USB_IRQn, configUSB_INTERRUPT_PRIORITY );
NVIC_EnableIRQ( USB_IRQn );
// connect to bus
DBG("Connecting to USB bus\n");
USBHwConnect(TRUE);
// echo any character received (do USB stuff in interrupt)
for( ;; )
{
c = VCOM_getchar();
if (c != EOF)
{
// Echo character back with INCREMENT_ECHO_BY offset, so for example if
// INCREMENT_ECHO_BY is 1 and 'A' is received, 'B' will be echoed back.
VCOM_putchar(c + INCREMENT_ECHO_BY );
}
}
}
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