/* USB Serial Example for Teensy USB Development Board

* http://www.pjrc.com/teensy/usb_serial.html

* Copyright (c) 2008,2010,2011 PJRC.COM, LLC

*

* Permission is hereby granted, free of charge, to any person obtaining a copy

* of this software and associated documentation files (the "Software"), to deal

* in the Software without restriction, including without limitation the rights

* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

* copies of the Software, and to permit persons to whom the Software is

* furnished to do so, subject to the following conditions:

*

* The above copyright notice and this permission notice shall be included in

* all copies or substantial portions of the Software.

*

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

* THE SOFTWARE.

*/

// Version 1.0: Initial Release

// Version 1.1: support Teensy++

// Version 1.2: fixed usb_serial_available

// Version 1.3: added transmit bandwidth test

// Version 1.4: added usb_serial_write

// Version 1.5: add support for Teensy 2.0

// Version 1.6: fix zero length packet bug

// Version 1.7: fix usb_serial_set_control

#define USB_SERIAL_PRIVATE_INCLUDE

#include "usb_serial.h"

/**************************************************************************

*

* Configurable Options

*

**************************************************************************/

// You can change these to give your code its own name. On Windows,

// these are only used before an INF file (driver install) is loaded.

#define STR_MANUFACTURER L"siro"

#define STR_PRODUCT L"Teensy USB Serial"

// All USB serial devices are supposed to have a serial number

// (according to Microsoft). On windows, a new COM port is created

// for every unique serial/vendor/product number combination. If

// you program 2 identical boards with 2 different serial numbers

// and they are assigned COM7 and COM8, each will always get the

// same COM port number because Windows remembers serial numbers.

//

// On Mac OS-X, a device file is created automatically which

// incorperates the serial number, eg, /dev/cu-usbmodem12341

//

// Linux by default ignores the serial number, and creates device

// files named /dev/ttyACM0, /dev/ttyACM1... in the order connected.

// Udev rules (in /etc/udev/rules.d) can define persistent device

// names linked to this serial number, as well as permissions, owner

// and group settings.

#define STR_SERIAL_NUMBER L"00001"

// Mac OS-X and Linux automatically load the correct drivers. On

// Windows, even though the driver is supplied by Microsoft, an

// INF file is needed to load the driver. These numbers need to

// match the INF file.

#define VENDOR_ID 0x16C0

#define PRODUCT_ID 0x047A

// When you write data, it goes into a USB endpoint buffer, which

// is transmitted to the PC when it becomes full, or after a timeout

// with no more writes. Even if you write in exactly packet-size

// increments, this timeout is used to send a "zero length packet"

// that tells the PC no more data is expected and it should pass

// any buffered data to the application that may be waiting. If

// you want data sent immediately, call usb_serial_flush_output().

#define TRANSMIT_FLUSH_TIMEOUT 5 /* in milliseconds */

// If the PC is connected but not "listening", this is the length

// of time before usb_serial_getchar() returns with an error. This

// is roughly equivilant to a real UART simply transmitting the

// bits on a wire where nobody is listening, except you get an error

// code which you can ignore for serial-like discard of data, or

// use to know your data wasn't sent.

#define TRANSMIT_TIMEOUT 25 /* in milliseconds */

// USB devices are supposed to implment a halt feature, which is

// rarely (if ever) used. If you comment this line out, the halt

// code will be removed, saving 116 bytes of space (gcc 4.3.0).

// This is not strictly USB compliant, but works with all major

// operating systems.

#define SUPPORT_ENDPOINT_HALT

/**************************************************************************

*

* Endpoint Buffer Configuration

*

**************************************************************************/

// These buffer sizes are best for most applications, but perhaps if you

// want more buffering on some endpoint at the expense of others, this

// is where you can make such changes. The AT90USB162 has only 176 bytes

// of DPRAM (USB buffers) and only endpoints 3 & 4 can double buffer.

#define ENDPOINT0_SIZE 16

#define CDC_ACM_ENDPOINT 2

#define CDC_RX_ENDPOINT 3

#define CDC_TX_ENDPOINT 4

#if defined(__AVR_AT90USB162__)

#define CDC_ACM_SIZE 16

#define CDC_ACM_BUFFER EP_SINGLE_BUFFER

#define CDC_RX_SIZE 32

#define CDC_RX_BUFFER EP_DOUBLE_BUFFER

#define CDC_TX_SIZE 32

#define CDC_TX_BUFFER EP_DOUBLE_BUFFER

#else

#define CDC_ACM_SIZE 16

#define CDC_ACM_BUFFER EP_SINGLE_BUFFER

#define CDC_RX_SIZE 64

#define CDC_RX_BUFFER EP_DOUBLE_BUFFER

#define CDC_TX_SIZE 64

#define CDC_TX_BUFFER EP_DOUBLE_BUFFER

#endif

static const uint8_t PROGMEM endpoint_config_table[] = {

0,

1, EP_TYPE_INTERRUPT_IN, EP_SIZE(CDC_ACM_SIZE) | CDC_ACM_BUFFER,

1, EP_TYPE_BULK_OUT, EP_SIZE(CDC_RX_SIZE) | CDC_RX_BUFFER,

1, EP_TYPE_BULK_IN, EP_SIZE(CDC_TX_SIZE) | CDC_TX_BUFFER

};

/**************************************************************************

*

* Descriptor Data

*

**************************************************************************/

// Descriptors are the data that your computer reads when it auto-detects

// this USB device (called "enumeration" in USB lingo). The most commonly

// changed items are editable at the top of this file. Changing things

// in here should only be done by those who've read chapter 9 of the USB

// spec and relevant portions of any USB class specifications!

static uint8_t PROGMEM device_descriptor[] = {

18, // bLength

1, // bDescriptorType

0x00, 0x02, // bcdUSB

2, // bDeviceClass

0, // bDeviceSubClass

0, // bDeviceProtocol

ENDPOINT0_SIZE, // bMaxPacketSize0

LSB(VENDOR_ID), MSB(VENDOR_ID), // idVendor

LSB(PRODUCT_ID), MSB(PRODUCT_ID), // idProduct

0x00, 0x01, // bcdDevice

1, // iManufacturer

2, // iProduct

3, // iSerialNumber

1 // bNumConfigurations

};

#define CONFIG1_DESC_SIZE (9+9+5+5+4+5+7+9+7+7)

static uint8_t PROGMEM config1_descriptor[CONFIG1_DESC_SIZE] = {

// configuration descriptor, USB spec 9.6.3, page 264-266, Table 9-10

9, // bLength;

2, // bDescriptorType;

LSB(CONFIG1_DESC_SIZE), // wTotalLength

MSB(CONFIG1_DESC_SIZE),

2, // bNumInterfaces

1, // bConfigurationValue

0, // iConfiguration

0xC0, // bmAttributes

50, // bMaxPower

// interface descriptor, USB spec 9.6.5, page 267-269, Table 9-12

9, // bLength

4, // bDescriptorType

0, // bInterfaceNumber

0, // bAlternateSetting

1, // bNumEndpoints

0x02, // bInterfaceClass

0x02, // bInterfaceSubClass

0x01, // bInterfaceProtocol

0, // iInterface

// CDC Header Functional Descriptor, CDC Spec 5.2.3.1, Table 26

5, // bFunctionLength

0x24, // bDescriptorType

0x00, // bDescriptorSubtype

0x10, 0x01, // bcdCDC

// Call Management Functional Descriptor, CDC Spec 5.2.3.2, Table 27

5, // bFunctionLength

0x24, // bDescriptorType

0x01, // bDescriptorSubtype

0x01, // bmCapabilities

1, // bDataInterface

// Abstract Control Management Functional Descriptor, CDC Spec 5.2.3.3, Table 28

4, // bFunctionLength

0x24, // bDescriptorType

0x02, // bDescriptorSubtype

0x06, // bmCapabilities

// Union Functional Descriptor, CDC Spec 5.2.3.8, Table 33

5, // bFunctionLength

0x24, // bDescriptorType

0x06, // bDescriptorSubtype

0, // bMasterInterface

1, // bSlaveInterface0

// endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13

7, // bLength

5, // bDescriptorType

CDC_ACM_ENDPOINT | 0x80, // bEndpointAddress

0x03, // bmAttributes (0x03=intr)

CDC_ACM_SIZE, 0, // wMaxPacketSize

64, // bInterval

// interface descriptor, USB spec 9.6.5, page 267-269, Table 9-12

9, // bLength

4, // bDescriptorType

1, // bInterfaceNumber

0, // bAlternateSetting

2, // bNumEndpoints

0x0A, // bInterfaceClass

0x00, // bInterfaceSubClass

0x00, // bInterfaceProtocol

0, // iInterface

// endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13

7, // bLength

5, // bDescriptorType

CDC_RX_ENDPOINT, // bEndpointAddress

0x02, // bmAttributes (0x02=bulk)

CDC_RX_SIZE, 0, // wMaxPacketSize

0, // bInterval

// endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13

7, // bLength

5, // bDescriptorType

CDC_TX_ENDPOINT | 0x80, // bEndpointAddress

0x02, // bmAttributes (0x02=bulk)

CDC_TX_SIZE, 0, // wMaxPacketSize

0 // bInterval

};

// If you're desperate for a little extra code memory, these strings

// can be completely removed if iManufacturer, iProduct, iSerialNumber

// in the device desciptor are changed to zeros.

struct usb_string_descriptor_struct {

};

static struct usb_string_descriptor_struct PROGMEM string0 = {

4,

3,

{0x0409}

};

static struct usb_string_descriptor_struct PROGMEM string1 = {

sizeof(STR_MANUFACTURER),

3,

STR_MANUFACTURER

};

static struct usb_string_descriptor_struct PROGMEM string2 = {

sizeof(STR_PRODUCT),

3,

STR_PRODUCT

};

static struct usb_string_descriptor_struct PROGMEM string3 = {

sizeof(STR_SERIAL_NUMBER),

3,

STR_SERIAL_NUMBER

};

// This table defines which descriptor data is sent for each specific

// request from the host (in wValue and wIndex).

static struct descriptor_list_struct {

} PROGMEM descriptor_list[] = {

{0x0100, 0x0000, device_descriptor, sizeof(device_descriptor)},

{0x0200, 0x0000, config1_descriptor, sizeof(config1_descriptor)},

{0x0300, 0x0000, (const uint8_t *)&string0, 4},

{0x0301, 0x0409, (const uint8_t *)&string1, sizeof(STR_MANUFACTURER)},

{0x0302, 0x0409, (const uint8_t *)&string2, sizeof(STR_PRODUCT)},

{0x0303, 0x0409, (const uint8_t *)&string3, sizeof(STR_SERIAL_NUMBER)}

};

#define NUM_DESC_LIST (sizeof(descriptor_list)/sizeof(struct descriptor_list_struct))

/**************************************************************************

*

* Variables - these are the only non-stack RAM usage

*

**************************************************************************/

// zero when we are not configured, non-zero when enumerated

static volatile uint8_t usb_configuration=0;

// the time remaining before we transmit any partially full

// packet, or send a zero length packet.

static volatile uint8_t transmit_flush_timer=0;

static uint8_t transmit_previous_timeout=0;

// serial port settings (baud rate, control signals, etc) set

// by the PC. These are ignored, but kept in RAM.

static uint8_t cdc_line_coding[7]={0x00, 0xE1, 0x00, 0x00, 0x00, 0x00, 0x08};

static uint8_t cdc_line_rtsdtr=0;

/**************************************************************************

*

* Public Functions - these are the API intended for the user

*

**************************************************************************/

// initialize USB serial

void usb_init(void)

{

HW_CONFIG();

USB_FREEZE(); // enable USB

PLL_CONFIG(); // config PLL, 16 MHz xtal

while (!(PLLCSR & (1<<PLOCK))) ; // wait for PLL lock

USB_CONFIG(); // start USB clock

UDCON = 0; // enable attach resistor

usb_configuration = 0;

cdc_line_rtsdtr = 0;

UDIEN = (1<<EORSTE)|(1<<SOFE);

sei();

}

// return 0 if the USB is not configured, or the configuration

// number selected by the HOST

uint8_t usb_configured(void)

{

return usb_configuration;

}

// get the next character, or -1 if nothing received

int16_t usb_serial_getchar(void)

{

uint8_t c, intr_state;

// interrupts are disabled so these functions can be

// used from the main program or interrupt context,

// even both in the same program!

intr_state = SREG;

cli();

if (!usb_configuration) {

SREG = intr_state;

sei();

return -1;

}

UENUM = CDC_RX_ENDPOINT;

retry:

c = UEINTX;

if (!(c & (1<<RWAL))) {

// no data in buffer

if (c & (1<<RXOUTI)) {

UEINTX = 0x6B;

goto retry;

}

SREG = intr_state;

return -1;

}

// take one byte out of the buffer

c = UEDATX;

// if buffer completely used, release it

if (!(UEINTX & (1<<RWAL))) UEINTX = 0x6B;

SREG = intr_state;

return c;

}

// number of bytes available in the receive buffer

uint8_t usb_serial_available(void)

{

uint8_t n=0, i, intr_state;

intr_state = SREG;

cli();

if (usb_configuration) {

UENUM = CDC_RX_ENDPOINT;

n = UEBCLX;

if (!n) {

i = UEINTX;

if (i & (1<<RXOUTI) && !(i & (1<<RWAL))) UEINTX = 0x6B;

}

}

SREG = intr_state;

return n;

}

// discard any buffered input

void usb_serial_flush_input(void)

{

uint8_t intr_state;

if (usb_configuration) {

intr_state = SREG;

cli();

UENUM = CDC_RX_ENDPOINT;

while ((UEINTX & (1<<RWAL))) {

UEINTX = 0x6B;

}

SREG = intr_state;

}

}

// transmit a character. 0 returned on success, -1 on error

int8_t usb_serial_putchar(uint8_t c)

{

uint8_t timeout, intr_state;

// if we're not online (enumerated and configured), error

if (!usb_configuration) return -1;

// interrupts are disabled so these functions can be

// used from the main program or interrupt context,

// even both in the same program!

intr_state = SREG;

cli();

UENUM = CDC_TX_ENDPOINT;

// if we gave up due to timeout before, don't wait again

if (transmit_previous_timeout) {

if (!(UEINTX & (1<<RWAL))) {

SREG = intr_state;

return -1;

}

transmit_previous_timeout = 0;

}

// wait for the FIFO to be ready to accept data

timeout = UDFNUML + TRANSMIT_TIMEOUT;

while (1) {

// are we ready to transmit?

if (UEINTX & (1<<RWAL)) break;

SREG = intr_state;

// have we waited too long? This happens if the user

// is not running an application that is listening

if (UDFNUML == timeout) {

transmit_previous_timeout = 1;

return -1;

}

// has the USB gone offline?

if (!usb_configuration) return -1;

// get ready to try checking again

intr_state = SREG;

cli();

UENUM = CDC_TX_ENDPOINT;

}

// actually write the byte into the FIFO

UEDATX = c;

// if this completed a packet, transmit it now!

if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A;

transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;

SREG = intr_state;

return 0;

}

// transmit a character, but do not wait if the buffer is full,

// 0 returned on success, -1 on buffer full or error

int8_t usb_serial_putchar_nowait(uint8_t c)

{

uint8_t intr_state;

if (!usb_configuration) return -1;

intr_state = SREG;

cli();

UENUM = CDC_TX_ENDPOINT;

if (!(UEINTX & (1<<RWAL))) {

// buffer is full

SREG = intr_state;

return -1;

}

// actually write the byte into the FIFO

UEDATX = c;

// if this completed a packet, transmit it now!

if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A;

transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;

SREG = intr_state;

return 0;

}

// transmit a buffer.

// 0 returned on success, -1 on error

// This function is optimized for speed! Each call takes approx 6.1 us overhead

// plus 0.25 us per byte. 12 Mbit/sec USB has 8.67 us per-packet overhead and

// takes 0.67 us per byte. If called with 64 byte packet-size blocks, this function

// can transmit at full USB speed using 43% CPU time. The maximum theoretical speed

// is 19 packets per USB frame, or 1216 kbytes/sec. However, bulk endpoints have the

// lowest priority, so any other USB devices will likely reduce the speed. Speed

// can also be limited by how quickly the PC-based software reads data, as the host

// controller in the PC will not allocate bandwitdh without a pending read request.

// (thanks to Victor Suarez for testing and feedback and initial code)

int8_t usb_serial_write(const uint8_t *buffer, uint16_t size)

{

uint8_t timeout, intr_state, write_size;

// if we're not online (enumerated and configured), error

if (!usb_configuration) return -1;

// interrupts are disabled so these functions can be

// used from the main program or interrupt context,

// even both in the same program!

intr_state = SREG;

cli();

UENUM = CDC_TX_ENDPOINT;

// if we gave up due to timeout before, don't wait again

if (transmit_previous_timeout) {

if (!(UEINTX & (1<<RWAL))) {

SREG = intr_state;

return -1;

}

transmit_previous_timeout = 0;

}

// each iteration of this loop transmits a packet

while (size) {

// wait for the FIFO to be ready to accept data

timeout = UDFNUML + TRANSMIT_TIMEOUT;

while (1) {

// are we ready to transmit?

if (UEINTX & (1<<RWAL)) break;

SREG = intr_state;

// have we waited too long? This happens if the user

// is not running an application that is listening

if (UDFNUML == timeout) {

transmit_previous_timeout = 1;

return -1;

}

// has the USB gone offline?

if (!usb_configuration) return -1;

// get ready to try checking again

intr_state = SREG;

cli();

UENUM = CDC_TX_ENDPOINT;

}

// compute how many bytes will fit into the next packet

write_size = CDC_TX_SIZE - UEBCLX;

if (write_size > size) write_size = size;

size -= write_size;

// write the packet

switch (write_size) {

#if (CDC_TX_SIZE == 64)

case 64: UEDATX = *buffer++;

case 63: UEDATX = *buffer++;

case 62: UEDATX = *buffer++;

case 61: UEDATX = *buffer++;

case 60: UEDATX = *buffer++;

case 59: UEDATX = *buffer++;

case 58: UEDATX = *buffer++;

case 57: UEDATX = *buffer++;

case 56: UEDATX = *buffer++;

case 55: UEDATX = *buffer++;

case 54: UEDATX = *buffer++;

case 53: UEDATX = *buffer++;

case 52: UEDATX = *buffer++;

case 51: UEDATX = *buffer++;

case 50: UEDATX = *buffer++;

case 49: UEDATX = *buffer++;

case 48: UEDATX = *buffer++;

case 47: UEDATX = *buffer++;

case 46: UEDATX = *buffer++;

case 45: UEDATX = *buffer++;

case 44: UEDATX = *buffer++;

case 43: UEDATX = *buffer++;

case 42: UEDATX = *buffer++;

case 41: UEDATX = *buffer++;

case 40: UEDATX = *buffer++;

case 39: UEDATX = *buffer++;

case 38: UEDATX = *buffer++;

case 37: UEDATX = *buffer++;

case 36: UEDATX = *buffer++;

case 35: UEDATX = *buffer++;

case 34: UEDATX = *buffer++;

case 33: UEDATX = *buffer++;

#endif

#if (CDC_TX_SIZE >= 32)

case 32: UEDATX = *buffer++;

case 31: UEDATX = *buffer++;

case 30: UEDATX = *buffer++;

case 29: UEDATX = *buffer++;

case 28: UEDATX = *buffer++;

case 27: UEDATX = *buffer++;

case 26: UEDATX = *buffer++;

case 25: UEDATX = *buffer++;

case 24: UEDATX = *buffer++;

case 23: UEDATX = *buffer++;

case 22: UEDATX = *buffer++;

case 21: UEDATX = *buffer++;

case 20: UEDATX = *buffer++;

case 19: UEDATX = *buffer++;

case 18: UEDATX = *buffer++;

case 17: UEDATX = *buffer++;

#endif

#if (CDC_TX_SIZE >= 16)

case 16: UEDATX = *buffer++;

case 15: UEDATX = *buffer++;

case 14: UEDATX = *buffer++;

case 13: UEDATX = *buffer++;

case 12: UEDATX = *buffer++;

case 11: UEDATX = *buffer++;

case 10: UEDATX = *buffer++;

case 9: UEDATX = *buffer++;

#endif

case 8: UEDATX = *buffer++;

case 7: UEDATX = *buffer++;

case 6: UEDATX = *buffer++;

case 5: UEDATX = *buffer++;

case 4: UEDATX = *buffer++;

case 3: UEDATX = *buffer++;

case 2: UEDATX = *buffer++;

default:

case 1: UEDATX = *buffer++;

case 0: break;

}

// if this completed a packet, transmit it now!

if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A;

transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;

SREG = intr_state;

}

return 0;

}

// immediately transmit any buffered output.

// This doesn't actually transmit the data - that is impossible!

// USB devices only transmit when the host allows, so the best

// we can do is release the FIFO buffer for when the host wants it

void usb_serial_flush_output(void)

{

uint8_t intr_state;

intr_state = SREG;

cli();

if (transmit_flush_timer) {

UENUM = CDC_TX_ENDPOINT;

UEINTX = 0x3A;

transmit_flush_timer = 0;

}

SREG = intr_state;

}

// functions to read the various async serial settings. These

// aren't actually used by USB at all (communication is always

// at full USB speed), but they are set by the host so we can

// set them properly if we're converting the USB to a real serial

// communication

uint32_t usb_serial_get_baud(void)

{

return *(uint32_t *)cdc_line_coding;

}

uint8_t usb_serial_get_stopbits(void)

{

return cdc_line_coding[4];

}

uint8_t usb_serial_get_paritytype(void)

{

return cdc_line_coding[5];

}

uint8_t usb_serial_get_numbits(void)

{

return cdc_line_coding[6];

}

uint8_t usb_serial_get_control(void)

{

return cdc_line_rtsdtr;

}

// write the control signals, DCD, DSR, RI, etc

// There is no CTS signal. If software on the host has transmitted

// data to you but you haven't been calling the getchar function,

// it remains buffered (either here or on the host) and can not be

// lost because you weren't listening at the right time, like it

// would in real serial communication.

int8_t usb_serial_set_control(uint8_t signals)

{

uint8_t intr_state;

intr_state = SREG;

cli();

if (!usb_configuration) {

// we're not enumerated/configured

SREG = intr_state;

return -1;

}

UENUM = CDC_ACM_ENDPOINT;

if (!(UEINTX & (1<<RWAL))) {

// unable to write

// TODO; should this try to abort the previously

// buffered message??

SREG = intr_state;

return -1;

}

UEDATX = 0xA1;

UEDATX = 0x20;

UEDATX = 0;

UEDATX = 0;

UEDATX = 0; // 0 seems to work nicely. what if this is 1??

UEDATX = 0;

UEDATX = 1;

UEDATX = 0;

UEDATX = signals;

UEINTX = 0x3A;

SREG = intr_state;

return 0;

}

/**************************************************************************

*

* Private Functions - not intended for general user consumption....

*

**************************************************************************/

// USB Device Interrupt - handle all device-level events

// the transmit buffer flushing is triggered by the start of frame

//

ISR(USB_GEN_vect)

{

uint8_t intbits, t;

intbits = UDINT;

UDINT = 0;

if (intbits & (1<<EORSTI)) {

UENUM = 0;

UECONX = 1;

UECFG0X = EP_TYPE_CONTROL;

UECFG1X = EP_SIZE(ENDPOINT0_SIZE) | EP_SINGLE_BUFFER;

UEIENX = (1<<RXSTPE);

usb_configuration = 0;

cdc_line_rtsdtr = 0;

}

if (intbits & (1<<SOFI)) {

if (usb_configuration) {

t = transmit_flush_timer;

if (t) {

transmit_flush_timer = --t;

if (!t) {

UENUM = CDC_TX_ENDPOINT;

UEINTX = 0x3A;

}

}

}

}

}

// Misc functions to wait for ready and send/receive packets

static inline void usb_wait_in_ready(void)

{

while (!(UEINTX & (1<<TXINI))) ;

}

static inline void usb_send_in(void)

{

UEINTX = ~(1<<TXINI);

}

static inline void usb_wait_receive_out(void)

{

while (!(UEINTX & (1<<RXOUTI))) ;

}

static inline void usb_ack_out(void)

{

UEINTX = ~(1<<RXOUTI);

}

// USB Endpoint Interrupt - endpoint 0 is handled here. The

// other endpoints are manipulated by the user-callable

// functions, and the start-of-frame interrupt.

//

ISR(USB_COM_vect)

{

uint8_t intbits;

const uint8_t *list;

const uint8_t *cfg;

uint8_t i, n, len, en;

uint8_t *p;

uint8_t bmRequestType;

uint8_t bRequest;

uint16_t wValue;

uint16_t wIndex;

uint16_t wLength;

uint16_t desc_val;

const uint8_t *desc_addr;

uint8_t desc_length;

UENUM = 0;

intbits = UEINTX;

if (intbits & (1<<RXSTPI)) {

bmRequestType = UEDATX;

bRequest = UEDATX;

wValue = UEDATX;

wValue |= (UEDATX << 8);

wIndex = UEDATX;

wIndex |= (UEDATX << 8);

wLength = UEDATX;

wLength |= (UEDATX << 8);

UEINTX = ~((1<<RXSTPI) | (1<<RXOUTI) | (1<<TXINI));

if (bRequest == GET_DESCRIPTOR) {

list = (const uint8_t *)descriptor_list;

for (i=0; ; i++) {

if (i >= NUM_DESC_LIST) {

UECONX = (1<<STALLRQ)|(1<<EPEN); //stall

return;

}

desc_val = pgm_read_word(list);

if (desc_val != wValue) {

list += sizeof(struct descriptor_list_struct);

continue;

}

list += 2;

desc_val = pgm_read_word(list);

if (desc_val != wIndex) {

list += sizeof(struct descriptor_list_struct)-2;

continue;

}

list += 2;

desc_addr = (const uint8_t *)pgm_read_word(list);

list += 2;

desc_length = pgm_read_byte(list);

break;

}

len = (wLength < 256) ? wLength : 255;

if (len > desc_length) len = desc_length;

do {

// wait for host ready for IN packet

do {

i = UEINTX;

} while (!(i & ((1<<TXINI)|(1<<RXOUTI))));

if (i & (1<<RXOUTI)) return; // abort

// send IN packet

n = len < ENDPOINT0_SIZE ? len : ENDPOINT0_SIZE;

for (i = n; i; i--) {

UEDATX = pgm_read_byte(desc_addr++);

}

len -= n;

usb_send_in();

} while (len || n == ENDPOINT0_SIZE);

return;

}

if (bRequest == SET_ADDRESS) {

usb_send_in();

usb_wait_in_ready();

UDADDR = wValue | (1<<ADDEN);

return;

}

if (bRequest == SET_CONFIGURATION && bmRequestType == 0) {

usb_configuration = wValue;

cdc_line_rtsdtr = 0;

transmit_flush_timer = 0;

usb_send_in();

cfg = endpoint_config_table;

for (i=1; i<5; i++) {

UENUM = i;

en = pgm_read_byte(cfg++);

UECONX = en;

if (en) {

UECFG0X = pgm_read_byte(cfg++);

UECFG1X = pgm_read_byte(cfg++);

}

}

UERST = 0x1E;

UERST = 0;

return;

}

if (bRequest == GET_CONFIGURATION && bmRequestType == 0x80) {

usb_wait_in_ready();

UEDATX = usb_configuration;

usb_send_in();

return;

}

if (bRequest == CDC_GET_LINE_CODING && bmRequestType == 0xA1) {

usb_wait_in_ready();

p = cdc_line_coding;

for (i=0; i<7; i++) {

UEDATX = *p++;

}

usb_send_in();

return;

}

if (bRequest == CDC_SET_LINE_CODING && bmRequestType == 0x21) {

usb_wait_receive_out();

p = cdc_line_coding;

for (i=0; i<7; i++) {

*p++ = UEDATX;

}

usb_ack_out();

usb_send_in();

return;

}

if (bRequest == CDC_SET_CONTROL_LINE_STATE && bmRequestType == 0x21) {

cdc_line_rtsdtr = wValue;

usb_wait_in_ready();

usb_send_in();

return;

}

if (bRequest == GET_STATUS) {

usb_wait_in_ready();

i = 0;

#ifdef SUPPORT_ENDPOINT_HALT

if (bmRequestType == 0x82) {

UENUM = wIndex;

if (UECONX & (1<<STALLRQ)) i = 1;

UENUM = 0;

}

#endif

UEDATX = i;

UEDATX = 0;

usb_send_in();

return;

}

#ifdef SUPPORT_ENDPOINT_HALT

if ((bRequest == CLEAR_FEATURE || bRequest == SET_FEATURE)

&& bmRequestType == 0x02 && wValue == 0) {

i = wIndex & 0x7F;

if (i >= 1 && i <= MAX_ENDPOINT) {

usb_send_in();

UENUM = i;

if (bRequest == SET_FEATURE) {

UECONX = (1<<STALLRQ)|(1<<EPEN);

} else {

UECONX = (1<<STALLRQC)|(1<<RSTDT)|(1<<EPEN);

UERST = (1 << i);

UERST = 0;

}

return;

}

}

#endif

}

UECONX = (1<<STALLRQ) | (1<<EPEN); // stall

}