Cours:LeonardoSerialUsb
Révision datée du 26 mars 2019 à 00:38 par Bjacquot (discussion | contributions)
Nous allons utiliser du code du site pjrc.com : https://www.pjrc.com/teensy/usb_serial.html
Nous aurons besoin des 2 fichiers suivants :
Fichier : usb_serial.h
#ifndef usb_serial_h__
#define usb_serial_h__
#include <stdint.h>
// setup
void usb_init(void); // initialize everything
uint8_t usb_configured(void); // is the USB port configured
// receiving data
int16_t usb_serial_getchar(void); // receive a character (-1 if timeout/error)
uint8_t usb_serial_available(void); // number of bytes in receive buffer
void usb_serial_flush_input(void); // discard any buffered input
// transmitting data
int8_t usb_serial_putchar(uint8_t c); // transmit a character
int8_t usb_serial_putchar_nowait(uint8_t c); // transmit a character, do not wait
int8_t usb_serial_write(const uint8_t *buffer, uint16_t size); // transmit a buffer
void usb_serial_flush_output(void); // immediately transmit any buffered output
// serial parameters
uint32_t usb_serial_get_baud(void); // get the baud rate
uint8_t usb_serial_get_stopbits(void); // get the number of stop bits
uint8_t usb_serial_get_paritytype(void);// get the parity type
uint8_t usb_serial_get_numbits(void); // get the number of data bits
uint8_t usb_serial_get_control(void); // get the RTS and DTR signal state
int8_t usb_serial_set_control(uint8_t signals); // set DSR, DCD, RI, etc
// constants corresponding to the various serial parameters
#define USB_SERIAL_DTR 0x01
#define USB_SERIAL_RTS 0x02
#define USB_SERIAL_1_STOP 0
#define USB_SERIAL_1_5_STOP 1
#define USB_SERIAL_2_STOP 2
#define USB_SERIAL_PARITY_NONE 0
#define USB_SERIAL_PARITY_ODD 1
#define USB_SERIAL_PARITY_EVEN 2
#define USB_SERIAL_PARITY_MARK 3
#define USB_SERIAL_PARITY_SPACE 4
#define USB_SERIAL_DCD 0x01
#define USB_SERIAL_DSR 0x02
#define USB_SERIAL_BREAK 0x04
#define USB_SERIAL_RI 0x08
#define USB_SERIAL_FRAME_ERR 0x10
#define USB_SERIAL_PARITY_ERR 0x20
#define USB_SERIAL_OVERRUN_ERR 0x40
// This file does not include the HID debug functions, so these empty
// macros replace them with nothing, so users can compile code that
// has calls to these functions.
#define usb_debug_putchar(c)
#define usb_debug_flush_output()
// Everything below this point is only intended for usb_serial.c
#ifdef USB_SERIAL_PRIVATE_INCLUDE
#include <avr/io.h>
#include <avr/pgmspace.h>
#include <avr/interrupt.h>
#define EP_TYPE_CONTROL 0x00
#define EP_TYPE_BULK_IN 0x81
#define EP_TYPE_BULK_OUT 0x80
#define EP_TYPE_INTERRUPT_IN 0xC1
#define EP_TYPE_INTERRUPT_OUT 0xC0
#define EP_TYPE_ISOCHRONOUS_IN 0x41
#define EP_TYPE_ISOCHRONOUS_OUT 0x40
#define EP_SINGLE_BUFFER 0x02
#define EP_DOUBLE_BUFFER 0x06
#define EP_SIZE(s) ((s) == 64 ? 0x30 : \
((s) == 32 ? 0x20 : \
((s) == 16 ? 0x10 : \
0x00)))
#define MAX_ENDPOINT 4
#define LSB(n) (n & 255)
#define MSB(n) ((n >> 8) & 255)
#if defined(__AVR_AT90USB162__)
#define HW_CONFIG()
#define PLL_CONFIG() (PLLCSR = ((1<<PLLE)|(1<<PLLP0)))
#define USB_CONFIG() (USBCON = (1<<USBE))
#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
#elif defined(__AVR_ATmega32U4__)
#define HW_CONFIG() (UHWCON = 0x01)
#define PLL_CONFIG() (PLLCSR = 0x12)
#define USB_CONFIG() (USBCON = ((1<<USBE)|(1<<OTGPADE)))
#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
#elif defined(__AVR_AT90USB646__)
#define HW_CONFIG() (UHWCON = 0x81)
#define PLL_CONFIG() (PLLCSR = 0x1A)
#define USB_CONFIG() (USBCON = ((1<<USBE)|(1<<OTGPADE)))
#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
#elif defined(__AVR_AT90USB1286__)
#define HW_CONFIG() (UHWCON = 0x81)
#define PLL_CONFIG() (PLLCSR = 0x16)
#define USB_CONFIG() (USBCON = ((1<<USBE)|(1<<OTGPADE)))
#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
#endif
// standard control endpoint request types
#define GET_STATUS 0
#define CLEAR_FEATURE 1
#define SET_FEATURE 3
#define SET_ADDRESS 5
#define GET_DESCRIPTOR 6
#define GET_CONFIGURATION 8
#define SET_CONFIGURATION 9
#define GET_INTERFACE 10
#define SET_INTERFACE 11
// HID (human interface device)
#define HID_GET_REPORT 1
#define HID_GET_PROTOCOL 3
#define HID_SET_REPORT 9
#define HID_SET_IDLE 10
#define HID_SET_PROTOCOL 11
// CDC (communication class device)
#define CDC_SET_LINE_CODING 0x20
#define CDC_GET_LINE_CODING 0x21
#define CDC_SET_CONTROL_LINE_STATE 0x22
#endif
#endif
Fichier : usb_serial.c
/* 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"Your Name"
#define STR_PRODUCT L"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"12345"
// 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!
const 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)
const 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 {
uint8_t bLength;
uint8_t bDescriptorType;
int16_t wString[];
};
const static struct usb_string_descriptor_struct PROGMEM string0 = {
4,
3,
{0x0409}
};
const static struct usb_string_descriptor_struct PROGMEM string1 = {
sizeof(STR_MANUFACTURER),
3,
STR_MANUFACTURER
};
const static struct usb_string_descriptor_struct PROGMEM string2 = {
sizeof(STR_PRODUCT),
3,
STR_PRODUCT
};
const 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).
const static struct descriptor_list_struct {
uint16_t wValue;
uint16_t wIndex;
const uint8_t *addr;
uint8_t length;
} 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;
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
}
Fichier : exemple.c
/* Simple example for Teensy USB Development Board
* http://www.pjrc.com/teensy/ * Copyright (c) 2008 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. */
- include <avr/io.h>
- include <avr/pgmspace.h>
- include <stdint.h>
- include <util/delay.h>
- include "usb_serial.h"
- define LED_CONFIG (DDRD |= (1<<6))
- define LED_ON (PORTD |= (1<<6))
- define LED_OFF (PORTD &= ~(1<<6))
- define CPU_PRESCALE(n) (CLKPR = 0x80, CLKPR = (n))
void send_str(const char *s); uint8_t recv_str(char *buf, uint8_t size); void parse_and_execute_command(const char *buf, uint8_t num);
- if 0
// Very simple character echo test int main(void) { CPU_PRESCALE(0); usb_init(); while (1) { int n = usb_serial_getchar(); if (n >= 0) usb_serial_putchar(n); } }
- else
// Basic command interpreter for controlling port pins int main(void) { char buf[32]; uint8_t n;
// set for 16 MHz clock, and turn on the LED CPU_PRESCALE(0); LED_CONFIG; LED_ON;
// initialize the USB, and then wait for the host // to set configuration. If the Teensy is powered // without a PC connected to the USB port, this // will wait forever. usb_init(); while (!usb_configured()) /* wait */ ; _delay_ms(1000);
while (1) { // wait for the user to run their terminal emulator program // which sets DTR to indicate it is ready to receive. while (!(usb_serial_get_control() & USB_SERIAL_DTR)) /* wait */ ;
// discard anything that was received prior. Sometimes the // operating system or other software will send a modem // "AT command", which can still be buffered. usb_serial_flush_input();
// print a nice welcome message send_str(PSTR("\r\nTeensy USB Serial Example, " "Simple Pin Control Shell\r\n\r\n" "Example Commands\r\n" " B0? Read Port B, pin 0\r\n" " C2=0 Write Port C, pin 1 LOW\r\n" " D6=1 Write Port D, pin 6 HIGH (D6 is LED pin)\r\n\r\n"));
// and then listen for commands and process them while (1) { send_str(PSTR("> ")); n = recv_str(buf, sizeof(buf)); if (n == 255) break; send_str(PSTR("\r\n")); parse_and_execute_command(buf, n); } } }
- endif
// Send a string to the USB serial port. The string must be in // flash memory, using PSTR // void send_str(const char *s) { char c; while (1) { c = pgm_read_byte(s++); if (!c) break; usb_serial_putchar(c); } }
// Receive a string from the USB serial port. The string is stored // in the buffer and this function will not exceed the buffer size. // A carriage return or newline completes the string, and is not // stored into the buffer. // The return value is the number of characters received, or 255 if // the virtual serial connection was closed while waiting. // uint8_t recv_str(char *buf, uint8_t size) { int16_t r; uint8_t count=0;
while (count < size) { r = usb_serial_getchar(); if (r != -1) { if (r == '\r' || r == '\n') return count; if (r >= ' ' && r <= '~') { *buf++ = r; usb_serial_putchar(r); count++; } } else { if (!usb_configured() || !(usb_serial_get_control() & USB_SERIAL_DTR)) { // user no longer connected return 255; } // just a normal timeout, keep waiting } } return count; }
// parse a user command and execute it, or print an error message // void parse_and_execute_command(const char *buf, uint8_t num) { uint8_t port, pin, val;
if (num < 3) { send_str(PSTR("unrecognized format, 3 chars min req'd\r\n")); return; } // first character is the port letter if (buf[0] >= 'A' && buf[0] <= 'F') { port = buf[0] - 'A'; } else if (buf[0] >= 'a' && buf[0] <= 'f') { port = buf[0] - 'a'; } else { send_str(PSTR("Unknown port \"")); usb_serial_putchar(buf[0]); send_str(PSTR("\", must be A - F\r\n")); return; } // second character is the pin number if (buf[1] >= '0' && buf[1] <= '7') { pin = buf[1] - '0'; } else { send_str(PSTR("Unknown pin \"")); usb_serial_putchar(buf[0]); send_str(PSTR("\", must be 0 to 7\r\n")); return; } // if the third character is a question mark, read the pin if (buf[2] == '?') { // make the pin an input *(uint8_t *)(0x21 + port * 3) &= ~(1 << pin); // read the pin val = *(uint8_t *)(0x20 + port * 3) & (1 << pin); usb_serial_putchar(val ? '1' : '0'); send_str(PSTR("\r\n")); return; } // if the third character is an equals sign, write the pin if (num >= 4 && buf[2] == '=') { if (buf[3] == '0') { // make the pin an output *(uint8_t *)(0x21 + port * 3) |= (1 << pin); // drive it low *(uint8_t *)(0x22 + port * 3) &= ~(1 << pin); return; } else if (buf[3] == '1') { // make the pin an output *(uint8_t *)(0x21 + port * 3) |= (1 << pin); // drive it high *(uint8_t *)(0x22 + port * 3) |= (1 << pin); return; } else { send_str(PSTR("Unknown value \"")); usb_serial_putchar(buf[3]); send_str(PSTR("\", must be 0 or 1\r\n")); return; } } // otherwise, error message send_str(PSTR("Unknown command \"")); usb_serial_putchar(buf[0]); send_str(PSTR("\", must be ? or =\r\n")); } </source>
