De nuevo GAMBAS o lo que gusten, pero ahora con USB CDC

Esta ocación presento a ustedes este pequeño hilo sobre algo que acabo de averiguar, y bueno lo escribo en primera por si a alguien ya le habia ocurrido o le habia surgido alguna duda sobre este tema, aunque de hecho esta información podrán también encontrarla en los siguientes lugares y ya tiene un poco de tiempo pero bueno le vamos a poner un poco de mas sabor

Pues debido a la falta puertos seriales en las laptops, y la gran cantidad de terreno que los dispositivos USB están ganando, las comunicaciones con los micros por el puerto serial no es una muy buena idea, si tenemos una laptop o una netbook. sin embargo si tienes un micro PIC18F2550 o alguno parecido, con CCS podemos generar un puerto virtual COM en Win2, esto a través del uso de una dll llamada mchpcdc.dll y funciona muy bien , pues bien, que pasa si queremos probar una aplicación similar, pero en nuestro linux???

Me puse a indagar un poco, puesto que pienso hacer algunas cosas con esto, y bueno para emular un puerto serie en Linux.

Según notas de estas páginas
http://www.linuxjournal.com/article/8366 (Esta no tiene relacion, solo se usa para los comandos )
http://www.ccsinfo.com/forum/viewtopic.php?t=40123
http://www.todopic.com.ar/foros/index.php?topic=12537
http://wiki.openmoko.org/wiki/USB_CDC_ACM

Es posible comunicar un micro grabado con las librerías usb cdc que tiene CCS, pero con la diferencia, de que en Linux en el kernel las tiene por defecto!!, esto en pocas palabras, no es necesario instalar nada, solo hay que comunicar y ya!

Pero como hacer esa comunicación??

Bueno, es simple, para esto use el programa de ejemplo de Gambas de comunicación con el puerto serial, y en la ruta que tiene únicamente se cambia la ruta por defecto /dev/ttyS0 por la que detecta Linux cuando conectes tu micro al puerto USB en mi caso fue /dev/ttyACM0, y listo funcionó!!

Los fuentes son los siguientes basados en los que nos muestra RedPIC (de hecho son casi los mismos !!)

Código:


///////////////////////////////////////////////////////////////////////////

////                        usb_desc_cdc.h                            ////

////                                                                  ////

//// An example set of device / configuration descriptors for use with ////

//// CCS's CDC Virtual COM Port driver (see usb_cdc.h)                ////

////                                                                  ////

//// Two examples are provided:                                        ////

////      ex_usb_serial.c                                              ////

////      ex_usb_serial2.c                                            ////

////                                                                  ////

///////////////////////////////////////////////////////////////////////////

////                                                                  ////

//// Version History:                                                  ////

////                                                                  ////

//// 10/28/05:                                                        ////

////    Bulk endpoint sizes updated to allow more than 255 byte        ////

////    packets.                                                      ////

////    Changed device to USB 1.10                                    ////

////                                                                  ////

///////////////////////////////////////////////////////////////////////////

////        (C) Copyright 1996,2005 Custom Computer Services          ////

//// This source code may only be used by licensed users of the CCS    ////

//// C compiler.  This source code may only be distributed to other    ////

//// licensed users of the CCS C compiler.  No other use,              ////

//// reproduction or distribution is permitted without written        ////

//// permission.  Derivative programs created using this software      ////

//// in object code form are not restricted in any way.                ////

///////////////////////////////////////////////////////////////////////////

 
#IFNDEF __USB_DEscriptORS__

#DEFINE __USB_DEscriptORS__

 
#include <usb.h>

 
 
//////////////////////////////////////////////////////////////////

///

///  start config descriptor

///  right now we only support one configuration descriptor.

///  the config, interface, class, and endpoint goes into this array.

///

//////////////////////////////////////////////////////////////////

 
  #DEFINE USB_TOTAL_CONFIG_LEN      67  //config+interface+class+endpoint+endpoint (2 endpoints)

 
  const char USB_CONFIG_DESC[] = {

  //IN ORDER TO COMPLY WITH WINDOWS HOSTS, THE ORDER OF THIS ARRAY MUST BE:

      //    config(s)

      //    interface(s)

      //    class(es)

      //    endpoint(s)

 
  //config_descriptor for config index 1

        USB_DESC_CONFIG_LEN, //length of descriptor size          ==0

        USB_DESC_CONFIG_TYPE, //constant CONFIGURATION (CONFIGURATION 0x02)    ==1

        USB_TOTAL_CONFIG_LEN,0, //size of all data returned for this config      ==2,3

        2, //number of interfaces this device supports      ==4

        0x01, //identifier for this configuration.  (IF we had more than one configurations)      ==5

        0x00, //index of string descriptor for this configuration      ==6

        0xC0, //bit 6=1 if self powered, bit 5=1 if supports remote wakeup (we don't), bits 0-4 unused and bit7=1        ==7

        0x32, //maximum bus power required (maximum milliamperes/2)  (0x32 = 100mA)  ==8

 
  //interface descriptor 0 (comm class interface)

        USB_DESC_INTERFACE_LEN, //length of descriptor      =9

        USB_DESC_INTERFACE_TYPE, //constant INTERFACE (INTERFACE 0x04)      =10

        0x00, //number defining this interface (IF we had more than one interface)    ==11

        0x00, //alternate setting    ==12

        1, //number of endpoints  ==13

        0x02, //class code, 02 = Comm Interface Class    ==14

        0x02, //subclass code, 2 = Abstract    ==15

        0x01, //protocol code, 1 = v.25ter      ==16

        0x00, //index of string descriptor for interface      ==17

 
  //class descriptor [functional header]

        5, //length of descriptor    ==18

        0x24, //dscriptor type (0x24 == )      ==19

        0, //sub type (0=functional header) ==20

        0x10,0x01, //      ==21,22 //cdc version

 
  //class descriptor [acm header]

        4, //length of descriptor    ==23

        0x24, //dscriptor type (0x24 == )      ==24

        2, //sub type (2=ACM)  ==25

        2, //capabilities    ==26  //we support Set_Line_Coding, Set_Control_Line_State, Get_Line_Coding, and the notification Serial_State.

 
  //class descriptor [union header]

        5, //length of descriptor    ==27

        0x24, //dscriptor type (0x24 == )      ==28

        6, //sub type (6=union)    ==29

        0, //master intf    ==30  //The interface number of the Communication or Dat a Cl ass interface, designated as the masteror controlling interface for the union.

        1, //save intf0      ==31  //Interface number of first slave or associated interface in the union. *

 
  //class descriptor [call mgmt header]

        5, //length of descriptor    ==32

        0x24, //dscriptor type (0x24 == )      ==33

        1, //sub type (1=call mgmt)  ==34

        0, //capabilities          ==35  //device does not handle call management itself

        1, //data interface        ==36  //interface number of data class interface

 
  //endpoint descriptor

        USB_DESC_ENDPOINT_LEN, //length of descriptor                  ==37

        USB_DESC_ENDPOINT_TYPE, //constant ENDPOINT (ENDPOINT 0x05)          ==38

        USB_CDC_COMM_IN_ENDPOINT | 0x80, //endpoint number and direction

        0x03, //transfer type supported (0x03 is interrupt)        ==40

        USB_CDC_COMM_IN_SIZE,0x00, //maximum packet size supported                  ==41,42

        250,  //polling interval, in ms.  (cant be smaller than 10)      ==43

 
  //interface descriptor 1 (data class interface)

        USB_DESC_INTERFACE_LEN, //length of descriptor      =44

        USB_DESC_INTERFACE_TYPE, //constant INTERFACE (INTERFACE 0x04)      =45

        0x01, //number defining this interface (IF we had more than one interface)    ==46

        0x00, //alternate setting    ==47

        2, //number of endpoints  ==48

        0x0A, //class code, 0A = Data Interface Class    ==49

        0x00, //subclass code      ==50

        0x00, //protocol code      ==51

        0x00, //index of string descriptor for interface      ==52

 
  //endpoint descriptor

        USB_DESC_ENDPOINT_LEN, //length of descriptor                  ==60

        USB_DESC_ENDPOINT_TYPE, //constant ENDPOINT (ENDPOINT 0x05)          ==61

        USB_CDC_DATA_OUT_ENDPOINT, //endpoint number and direction (0x02 = EP2 OUT)      ==62

        0x02, //transfer type supported (0x02 is bulk)        ==63

//        make8(USB_CDC_DATA_OUT_SIZE,0),make8(USB_CDC_DATA_OUT_SIZE,1), //maximum packet size supported                  ==64, 65

        USB_CDC_DATA_OUT_SIZE & 0xFF, (USB_CDC_DATA_OUT_SIZE >> 8) & 0xFF, //maximum packet size supported                  ==64, 65

        250,  //polling interval, in ms.  (cant be smaller than 10)      ==66

 
  //endpoint descriptor

        USB_DESC_ENDPOINT_LEN, //length of descriptor                  ==53

        USB_DESC_ENDPOINT_TYPE, //constant ENDPOINT (ENDPOINT 0x05)          ==54

        USB_CDC_DATA_IN_ENDPOINT | 0x80, //endpoint number and direction (0x82 = EP2 IN)      ==55

        0x02, //transfer type supported (0x02 is bulk)        ==56

//        make8(USB_CDC_DATA_IN_SIZE,0),make8(USB_CDC_DATA_IN_SIZE,1), //maximum packet size supported                  ==57, 58

        USB_CDC_DATA_IN_SIZE & 0xFF, (USB_CDC_DATA_IN_SIZE >> 8) & 0xFF, //maximum packet size supported                  ==64, 65

        250,  //polling interval, in ms.  (cant be smaller than 10)      ==59

  };

 
  //****** BEGIN CONFIG DEscriptOR LOOKUP TABLES ********

  //since we can't make pointers to constants in certain pic16s, this is an offset table to find

  //  a specific descriptor in the above table.

 
  //the maximum number of interfaces seen on any config

  //for example, if config 1 has 1 interface and config 2 has 2 interfaces you must define this as 2

  #define USB_MAX_NUM_INTERFACES  2

 
  //define how many interfaces there are per config.  [0] is the first config, etc.

  const char USB_NUM_INTERFACES[USB_NUM_CONFIGURATIONS]={2};

 
  //define where to find class descriptors

  //first dimension is the config number

  //second dimension specifies which interface

  //last dimension specifies which class in this interface to get, but most will only have 1 class per interface

  //if a class descriptor is not valid, set the value to 0xFFFF

  const int16 USB_CLASS_DEscriptORS[USB_NUM_CONFIGURATIONS][USB_MAX_NUM_INTERFACES][4]=

  {

  //config 1

      //interface 0

        //class 1-4

        18,23,27,32,

      //interface 1

        //no classes for this interface

        0xFFFF,0xFFFF,0xFFFF,0xFFFF

  };

 
  #if (sizeof(USB_CONFIG_DESC) != USB_TOTAL_CONFIG_LEN)

      #error USB_TOTAL_CONFIG_LEN not defined correctly

  #endif

 
 
//////////////////////////////////////////////////////////////////

///

///  start device descriptors

///

//////////////////////////////////////////////////////////////////

 
  const char USB_DEVICE_DESC[USB_DESC_DEVICE_LEN] ={

      //starts of with device configuration. only one possible

        USB_DESC_DEVICE_LEN, //the length of this report  ==0

        0x01, //the constant DEVICE (DEVICE 0x01)  ==1

        0x10,0x01, //usb version in bcd  ==2,3

        0x02, //class code. 0x02=Communication Device Class ==4

        0x00, //subclass code ==5

        0x00, //protocol code ==6

        USB_MAX_EP0_PACKET_LENGTH, //max packet size for endpoint 0. (SLOW SPEED SPECIFIES 8) ==7

 
        0xD8,0x04,          //vendor id (0x04D8 is Microchip)

        0x0A,0x00,          //product id

 
// RR2 cambiado para      0x61,0x04, //vendor id (0x04D8 is Microchip, or is it 0x0461 ??)  ==8,9

// compatibilidad con .inf 0x33,0x00, //product id  ==10,11

// de Microchip

 
        0x00,0x01, //device release number  ==12,13

        0x01, //index of string description of manufacturer. therefore we point to string_1 array (see below)  ==14

        0x02, //index of string descriptor of the product  ==15

        0x00, //index of string descriptor of serial number  ==16

        USB_NUM_CONFIGURATIONS  //number of possible configurations  ==17

  };

 
 
//////////////////////////////////////////////////////////////////

///

///  start string descriptors

///  String 0 is a special language string, and must be defined.  People in U.S.A. can leave this alone.

///

///  You must define the length else get_next_string_character() will not see the string

///  Current code only supports 10 strings (0 thru 9)

///

//////////////////////////////////////////////////////////////////

 
//the offset of the starting location of each string.  offset[0] is the start of string 0, offset[1] is the start of string 1, etc.

char USB_STRING_DESC_OFFSET[]={0,4,12};

 
char const USB_STRING_DESC[]={

  //string 0

        4, //length of string index

        USB_DESC_STRING_TYPE, //descriptor type 0x03 (STRING)

        0x09,0x04,  //Microsoft Defined for US-English

  //string 1

        8, //length of string index

        USB_DESC_STRING_TYPE, //descriptor type 0x03 (STRING)

        'I',0,

        'S',0,

        'C',0,

  //string 2 --> nombre del dispositivo

        22, //length of string index

        USB_DESC_STRING_TYPE, //descriptor type 0x03 (STRING)

        'A',0,

        'n',0,

        'e',0,

        'm',0,

        'o',0,

        'm',0,

        'e',0,

        't',0,

        'r',0

        'o',0

};

 
#ENDIF



Código:


/////////////////////////////////////////////////////////////////////////

////                                                                ////

////                            usb_cdc.h                            ////

////                                                                ////

//// Library for adding a virtual COM port on your PC over USB using ////

//// the standard Communication Device Class (CDC) specification.    ////

//// Including this file in your code will add all USB code,        ////

//// interrupts, descriptors and handlers required.  No other        ////

//// modifications need to be made.                                  ////

////                                                                ////

//// This library creates a virtual RS232 link between the PC and    ////

//// the PIC, therefore the library provided will be familiar to    ////

//// anyone with standard UART stream I/O:                          ////

////                                                                ////

//// usb_cdc_kbhit() - Returns TRUE if there is one or more          ////

////      character received and waiting in the receive buffer.      ////

////                                                                ////

//// usb_cdc_getc() - Gets a character from the receive buffer.  If  ////

////      there is no data in the receive buffer it will wait until  ////

////      there is data in the receive buffer.  If you do not want  ////

////      to wait in an infinit loop, use usb_cdc_kbhit() first to  ////

////      check if there is data before calling usb_cdc_getc().      ////

////                                                                ////

//// usb_cdc_putc(char c) - Puts a character into the transmit      ////

////      buffer.  If the transmit buffer is full it will wait until ////

////      the transmit buffer is not full before putting the char    ////

////      into the transmit buffer.  The transmit buffer is read by  ////

////      the PC very quickly, and therefore the buffer should only  ////

////      be full for a few milli-seconds.  If you are concerned    ////

////      and don't want to be stuck in a long or infinite loop,    ////

////      use usb_cdc_putready() to see if there is space in the    ////

////      transmit buffer before putting data into the transmit      ////

////      buffer.                                                    ////

////                                                                ////

//// usb_cdc_putready() - Returns TRUE if there is room left in the  ////

////      transmit buffer for another character.                    ////

////                                                                ////

//// usb_cdc_connected() - Returns TRUE if we received a            ////

////      Set_Line_Coding.  On most serial terminal programs (such  ////

////      as Hyperterminal), they will send a Set_Line_Coding        ////

////      message when the program starts and it opens the virtual  ////

////      COM port.  This is a simple way to determine if the PC    ////

////      is ready to display data on a serial terminal program,    ////

////      but is not garaunteed to work all the time or on other    ////

////      terminal programs.                                        ////

////                                                                ////

//// usb_cdc_putc_fast(char c) - Similar to usb_cdc_putc(), except  ////

////      if the transmit buffer is full it will skip the char.      ////

////                                                                ////

//// usb_cdc_line_coding - A structure used for Set_Line_Coding and  ////

////      Get_Line_Coding.  Most of the time you can ignore this.  ////

////                                                                ////

//// usb_cdc_break - If the PC has sent a break command, this will  ////

////      hold the break time (in milli-seconds).  If the PC sends  ////

////      a value of 0xFFFF the device is supposed to hold the      ////

////      break until it sends a value of 0                        ////

////                                                                ////

//// usb_cdc_carrier - Where Set_Control_Line_State value is stored. ////

////      Of most relevance is the field dte_present, which is the  ////

////      DTR setting.                                              ////

////                                                                ////

//// The following functions are also provided, and are ports of the ////

//// I/O functions in input.c.  See input.c and the CCS manual for  ////

//// documentation:                                                  ////

////  get_float_usb() - Read a float number from the user          ////

////  get_long_usb() - Read a long number from the user            ////

////  get_int_usb() - Read an integer number from the user          ////

////  get_string_usb(char *s, int max) - Read a string from the user. ////

////  gethex_usb() - Read a byte, in HEX, from the user            ////

////  gethex1_usb() - Read a HEX character                          ////

////                                                                ////

//// This driver will load all the rest of the USB code, and a set  ////

//// of descriptors that will properly describe a CDC device for a  ////

//// virtual COM port (usb_desc_cdc.h)                              ////

////                                                                ////

//// An .INF file is provided (cdc_NTXP.inf) that will load the      ////

//// standard CDC drivers for a virtual COM port in Windows          ////

//// NT/2000/XP and above.  Unfortunately we do not provide an .inf  ////

//// file for Windows 98 and ME.                                    ////

////                                                                ////

/////////////////////////////////////////////////////////////////////////

////                                                                ////

//// VERSION HISTORY                                                ////

////                                                                ////

//// October 27th, 2005: Changed the way incoming packets are        ////

////              handled in that CDC driver will not flush        ////

////              endpoint until user has handled all data.  This  ////

////              will prevent overflows as the USB will NAK        ////

////              incoming packets until it is ready to receive    ////

////              more.                                            ////

////            When using 18F4550 family, the RX buffer is          ////

////              mapped directly to the endpoint buffer - this    ////

////              saves a chunk of RAM.                            ////

////            When using the 18F4550 family, you can increase      ////

////              the TX and RX size over 64 bytes.                ////

////            No longer send 0len packets in the TBE interrupt.    ////

////            Hopefully fixed bugs that caused random crashes      ////

////              if you tried sending more than 64 bytes.          ////

////                                                                ////

//// July 6th, 2005: Global interrupts disabled when writing to TX  ////

////                  buffer.                                      ////

////                                                                ////

//// July 1st, 2005: Initial Release.                                ////

////                                                                ////

/////////////////////////////////////////////////////////////////////////

////        (C) Copyright 1996,2005 Custom Computer Services        ////

//// This source code may only be used by licensed users of the CCS  ////

//// C compiler.  This source code may only be distributed to other  ////

//// licensed users of the CCS C compiler.  No other use,            ////

//// reproduction or distribution is permitted without written      ////

//// permission.  Derivative programs created using this software    ////

//// in object code form are not restricted in any way.              ////

/////////////////////////////////////////////////////////////////////////

 
 
//api for the user:

#define usb_cdc_kbhit() (usb_cdc_get_buffer_status.got)

#define usb_cdc_putready() (usb_cdc_put_buffer_nextin<USB_CDC_DATA_IN_SIZE)

#define usb_cdc_connected() (usb_cdc_got_set_line_coding)

void usb_cdc_putc_fast(char c);

char usb_cdc_getc(void);

void usb_cdc_putc(char c);

 
http://input.c ported to use CDC:

float get_float_usb();

signed long get_long_usb();

signed int get_int_usb();

void get_string_usb(char* s, int max);

BYTE gethex_usb();

BYTE gethex1_usb();

 
//functions automatically called by USB handler code

void usb_isr_tkn_cdc(void);

void usb_cdc_init(void);

void usb_isr_tok_out_cdc_control_dne(void);

void usb_isr_tok_in_cdc_data_dne(void);

void usb_isr_tok_out_cdc_data_dne(void);

 
void usb_cdc_flush_out_buffer(void);

 
//Tells the CCS PIC USB firmware to include HID handling code.

#DEFINE USB_HID_DEVICE  FALSE

#DEFINE USB_CDC_DEVICE  TRUE

 
#define USB_CDC_COMM_IN_ENDPOINT      1

#define USB_CDC_COMM_IN_SIZE          8

#define USB_EP1_TX_ENABLE  USB_ENABLE_INTERRUPT

#define USB_EP1_TX_SIZE  USB_CDC_COMM_IN_SIZE

 
//pic to pc endpoint config

#define USB_CDC_DATA_IN_ENDPOINT      2

#define USB_CDC_DATA_IN_SIZE          64

#define USB_EP2_TX_ENABLE  USB_ENABLE_BULK

#define USB_EP2_TX_SIZE  USB_CDC_DATA_IN_SIZE

 
//pc to pic endpoint config

#define USB_CDC_DATA_OUT_ENDPOINT      2

#define USB_CDC_DATA_OUT_SIZE          64

#define USB_EP2_RX_ENABLE  USB_ENABLE_BULK

#define USB_EP2_RX_SIZE  USB_CDC_DATA_OUT_SIZE

 
/////////////////////////////////////////////////////////////////////////////

//

// Include the CCS USB Libraries.  See the comments at the top of these

// files for more information

//

/////////////////////////////////////////////////////////////////////////////

#ifndef __USB_PIC_PERIF__

#define __USB_PIC_PERIF__    1

#endif

 
#if __USB_PIC_PERIF__

 #if defined(__PCM__)

  #error CDC requires bulk mode!  PIC16C7x5 does not have bulk mode

 #else

  #include <pic18_usb.h>  //Microchip 18Fxx5x hardware layer for usb.c

 #endif

#else

 #include <usbn960x.c>  //National 960x hardware layer for usb.c

#endif

#include ".\include\rr2_USB_Cdc_Monitor.h"    //USB Configuration and Device descriptors for this UBS device

#include <usb.c>        //handles usb setup tokens and get descriptor reports

 
struct {

        int32  dwDTERrate;  //data terminal rate, in bits per second

        int8    bCharFormat;  //num of stop bits (0=1, 1=1.5, 2=2)

        int8    bParityType;  //parity (0=none, 1=odd, 2=even, 3=mark, 4=space)

        int8    bDataBits;    //data bits (5,6,7,8 or 16)

} usb_cdc_line_coding;

 
//length of time, in ms, of break signal as we received in a SendBreak message.

//if ==0xFFFF, send break signal until we receive a 0x0000.

int16 usb_cdc_break;

 
int8 usb_cdc_encapsulated_cmd[8];

 
int8 usb_cdc_put_buffer[USB_CDC_DATA_IN_SIZE];

int1 usb_cdc_put_buffer_free;

#if USB_CDC_DATA_IN_SIZE>=0x100

 int16 usb_cdc_put_buffer_nextin=0;

// int16 usb_cdc_last_data_packet_size;

#else

 int8 usb_cdc_put_buffer_nextin=0;

// int8 usb_cdc_last_data_packet_size;

#endif

 
struct {

  int1 got;

  #if USB_CDC_DATA_OUT_SIZE>=0x100

  int16 len;

  int16 index;

  #else

  int8 len;

  int8 index;

  #endif

} usb_cdc_get_buffer_status;

 
int8 usb_cdc_get_buffer_status_buffer[USB_CDC_DATA_OUT_SIZE];

#if (defined(__PIC__))

 #if __PIC__

  //#locate usb_cdc_get_buffer_status_buffer=0x500+(2*USB_MAX_EP0_PACKET_LENGTH)+USB_CDC_COMM_IN_SIZE

  #if USB_MAX_EP0_PACKET_LENGTH==8

    #locate usb_cdc_get_buffer_status_buffer=0x500+24

  #elif USB_MAX_EP0_PACKET_LENGTH==64

    #locate usb_cdc_get_buffer_status_buffer=0x500+136

  #else

  #error CCS BUG WONT LET ME USE MATH IN LOCATE

  #endif

 #endif

#endif

 
int1 usb_cdc_got_set_line_coding;

 
struct  {

  int1 dte_present; //1=DTE present, 0=DTE not present

  int1 active;      //1=activate carrier, 0=deactivate carrier

  int reserved:6;

} usb_cdc_carrier;

 
enum {USB_CDC_OUT_NOTHING=0, USB_CDC_OUT_COMMAND=1, USB_CDC_OUT_LINECODING=2, USB_CDC_WAIT_0LEN=3} __usb_cdc_state=0;

 
#byte INTCON=0xFF2

#bit INT_GIE=INTCON.7

 
//handle OUT token done interrupt on endpoint 0 [read encapsulated cmd and line coding data]

void usb_isr_tok_out_cdc_control_dne(void) {

  debug_usb(debug_putc,"CDC %X ",__usb_cdc_state);

 
  switch (__usb_cdc_state) {

      //printf(putc_tbe,"@%X@\r\n", __usb_cdc_state);

      case USB_CDC_OUT_COMMAND:

        //usb_get_packet(0, usb_cdc_encapsulated_cmd, 8);

        memcpy(usb_cdc_encapsulated_cmd, usb_ep0_rx_buffer,8);

        #if USB_MAX_EP0_PACKET_LENGTH==8

        __usb_cdc_state=USB_CDC_WAIT_0LEN;

        usb_request_get_data();

        #else

        usb_put_0len_0();

        __usb_cdc_state=0;

        #endif

        break;

 
    #if USB_MAX_EP0_PACKET_LENGTH==8

      case USB_CDC_WAIT_0LEN:

        usb_put_0len_0();

        __usb_cdc_state=0;

        break;

    #endif

 
      case USB_CDC_OUT_LINECODING:

        //usb_get_packet(0, &usb_cdc_line_coding, 7);

        //printf(putc_tbe,"\r\n!GSLC FIN!\r\n");

        memcpy(&usb_cdc_line_coding, usb_ep0_rx_buffer,7);

        __usb_cdc_state=0;

        usb_put_0len_0();

        break;

 
      default:

        __usb_cdc_state=0;

        usb_init_ep0_setup();

        break;

  }

}

 
//handle IN token on 0 (setup packet)

void usb_isr_tkn_cdc(void) {

  //make sure the request goes to a CDC interface

  if ((usb_ep0_rx_buffer[4] == 1) || (usb_ep0_rx_buffer[4] == 0)) {

      //printf(putc_tbe,"!%X!\r\n", usb_ep0_rx_buffer[1]);

      switch(usb_ep0_rx_buffer[1]) {

        case 0x00:  //send_encapsulated_command

            __usb_cdc_state=USB_CDC_OUT_COMMAND;

            usb_request_get_data();

            break;

 
        case 0x01:  //get_encapsulated_command

            memcpy(usb_ep0_tx_buffer, usb_cdc_encapsulated_cmd, 8);

            usb_request_send_response(usb_ep0_rx_buffer[6]);  //send wLength bytes

            break;

 
        case 0x20:  //set_line_coding

            debug_usb(debug_putc,"!GSLC!");

            __usb_cdc_state=USB_CDC_OUT_LINECODING;

            usb_cdc_got_set_line_coding=TRUE;

            usb_request_get_data();

            break;

 
        case 0x21:  //get_line_coding

            memcpy(usb_ep0_tx_buffer, &usb_cdc_line_coding, sizeof(usb_cdc_line_coding));

            usb_request_send_response(sizeof(usb_cdc_line_coding)); //send wLength bytes

            break;

 
        case 0x22:  //set_control_line_state

            usb_cdc_carrier=usb_ep0_rx_buffer[2];

            usb_put_0len_0();

            break;

 
        case 0x23:  //send_break

            usb_cdc_break=make16(usb_ep0_rx_buffer[2],usb_ep0_rx_buffer[3]);

            usb_put_0len_0();

            break;

 
        default:

            usb_request_stall();

            break;

      }

  }

}

 
//handle OUT token done interrupt on endpoint 3 [buffer incoming received chars]

void usb_isr_tok_out_cdc_data_dne(void) {

  usb_cdc_get_buffer_status.got=TRUE;

  usb_cdc_get_buffer_status.index=0;

#if (defined(__PIC__))

  #if __PIC__

    usb_cdc_get_buffer_status.len=usb_rx_packet_size(USB_CDC_DATA_OUT_ENDPOINT);

  #else

    usb_cdc_get_buffer_status.len=usb_get_packet_buffer(

      USB_CDC_DATA_OUT_ENDPOINT,&usb_cdc_get_buffer_status_buffer[0],USB_CDC_DATA_OUT_SIZE);

  #endif

#else

  usb_cdc_get_buffer_status.len=usb_get_packet_buffer(

      USB_CDC_DATA_OUT_ENDPOINT,&usb_cdc_get_buffer_status_buffer[0],USB_CDC_DATA_OUT_SIZE);

#endif

}

 
//handle IN token done interrupt on endpoint 2 [transmit buffered characters]

void usb_isr_tok_in_cdc_data_dne(void) {

  if (usb_cdc_put_buffer_nextin) {

      usb_cdc_flush_out_buffer();

  }

  //send a 0len packet if needed

//  else if (usb_cdc_last_data_packet_size==USB_CDC_DATA_IN_SIZE) {

//      usb_cdc_last_data_packet_size=0;

//      printf(putc_tbe, "FL 0\r\n");

//      usb_put_packet(USB_CDC_DATA_IN_ENDPOINT,0,0,USB_DTS_TOGGLE);

//  }

  else {

      usb_cdc_put_buffer_free=TRUE;

      //printf(putc_tbe, "FL DONE\r\n");

  }

}

 
void usb_cdc_flush_out_buffer(void) {

  if (usb_cdc_put_buffer_nextin) {

      usb_cdc_put_buffer_free=FALSE;

      //usb_cdc_last_data_packet_size=usb_cdc_put_buffer_nextin;

      //printf(putc_tbe, "FL %U\r\n", usb_cdc_put_buffer_nextin);

      usb_put_packet(USB_CDC_DATA_IN_ENDPOINT,usb_cdc_put_buffer,usb_cdc_put_buffer_nextin,USB_DTS_TOGGLE);

      usb_cdc_put_buffer_nextin=0;

  }

}

 
void usb_cdc_init(void) {

  usb_cdc_line_coding.dwDTERrate=9600;

  usb_cdc_line_coding.bCharFormat=0;

  usb_cdc_line_coding.bParityType=0;

  usb_cdc_line_coding.bDataBits=8;

  (int8)usb_cdc_carrier=0;

  usb_cdc_got_set_line_coding=FALSE;

  usb_cdc_break=0;

  usb_cdc_put_buffer_nextin=0;

  usb_cdc_get_buffer_status.got=0;

  usb_cdc_put_buffer_free=TRUE;

}

 
////////////////// END USB CONTROL HANDLING //////////////////////////////////

 
////////////////// BEGIN USB<->RS232 CDC LIBRARY /////////////////////////////

 
char usb_cdc_getc(void) {

  char c;

 
  while (!usb_cdc_kbhit()) {}

 
  c=usb_cdc_get_buffer_status_buffer[usb_cdc_get_buffer_status.index++];

  if (usb_cdc_get_buffer_status.index >= usb_cdc_get_buffer_status.len) {

      usb_cdc_get_buffer_status.got=FALSE;

      usb_flush_out(USB_CDC_DATA_OUT_ENDPOINT, USB_DTS_TOGGLE);

  }

 
  return(c);

}

 
void usb_cdc_putc_fast(char c) {

  int1 old_gie;

 
  //disable global interrupts

  old_gie=INT_GIE;

  INT_GIE=0;

 
  if (usb_cdc_put_buffer_nextin >= USB_CDC_DATA_IN_SIZE) {

      usb_cdc_put_buffer_nextin=USB_CDC_DATA_IN_SIZE-1;  //we just overflowed the buffer!

  }

  usb_cdc_put_buffer[usb_cdc_put_buffer_nextin++]=c;

 
  //renable global interrupts

  INT_GIE=old_gie;

 
  /*

  if (usb_tbe(USB_CDC_DATA_IN_ENDPOINT)) {

      if (usb_cdc_put_buffer_nextin)

        usb_cdc_flush_out_buffer();

  }

  */

  if (usb_cdc_put_buffer_free) {

      usb_cdc_flush_out_buffer();

  }

}

 
void usb_cdc_putc(char c) {

  while (!usb_cdc_putready()) {

      if (usb_cdc_put_buffer_free) {

        usb_cdc_flush_out_buffer();

      }

      //delay_ms(500);

      //printf(putc_tbe,"TBE=%U CNT=%U LST=%U\r\n",usb_tbe(USB_CDC_DATA_IN_ENDPOINT), usb_cdc_put_buffer_nextin, usb_cdc_last_data_packet_size);

  }

  usb_cdc_putc_fast(c);

}

 
#include <ctype.h>

 
BYTE gethex1_usb() {

  char digit;

 
  digit = usb_cdc_getc();

 
  usb_cdc_putc(digit);

 
  if(digit<='9')

    return(digit-'0');

  else

    return((toupper(digit)-'A')+10);

}

 
BYTE gethex_usb() {

  int lo,hi;

 
  hi = gethex1_usb();

  lo = gethex1_usb();

  if(lo==0xdd)

    return(hi);

  else

    return( hi*16+lo );

}

 
void get_string_usb(char* s, int max) {

  int len;

  char c;

 
  --max;

  len=0;

  do {

    c=usb_cdc_getc();

    if(c==8) {  // Backspace

        if(len>0) {

          len--;

          usb_cdc_putc(c);

          usb_cdc_putc(' ');

          usb_cdc_putc(c);

        }

    } else if ((c>=' ')&&(c<='~'))

      if(len<max) {

        s[len++]=c;

        usb_cdc_putc(c);

      }

  } while(c!=13);

  s[len]=0;

}

 
 
// stdlib.h is required for the ato_ conversions

// in the following functions

#ifdef _STDLIB

 
signed int get_int_usb() {

  char s[5];

  signed int i;

 
  get_string_usb(s, 5);

 
  i=atoi(s);

  return(i);

}

 
signed long get_long_usb() {

  char s[7];

  signed long l;

 
  get_string_usb(s, 7);

  l=atol(s);

  return(l);

}

 
float get_float_usb() {

  char s[20];

  float f;

 
  get_string_usb(s, 20);

  f = atof(s);

  return(f);

}

 
#endif



Código:



//************************************************
//*ESTE PROGRAMA CONVIERTE LA SEÑAL DE RS232 A  *
//*USB. PRIMERO RECIBE EL BYTE QUE PROVIENE DE  *
//*EL RS232 Y LO ALMACENA EN LET1. POSTERIORMENTE*
//*LO PONE EN EL BUFFER DE ENVIO DEL USB Y ES    *
//*ENVIADO POR USB. EL PRIMER BYTE QUE RECIBE    *
//*ES EL BYTE QUE MANDA.                        *
//************************************************


#include <18F2550.h>
#fuses HSPLL,NOWDT,NOPROTECT,NOLVP,NODEBUG,USBDIV,PLL5,CPUDIV1,VREGEN

#use delay(clock=48000000)
#include ".\include\usb_cdc.h"
#include ".\include\rr2_USB_Cdc_Monitor.h"

#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, FORCE_SW)  //manejo del RS232

///PROGRAMA
void main(void)
{
  char let1;

  delay_ms(300);
  usb_cdc_init();
  usb_init();

  while(!usb_cdc_connected()) {}
 
  do{      //hace todo este codigo mientras este conectado
  if (usb_enumerated()){  //Si el dispositivo ya fué enumerado
  printf(usb_cdc_putc,"Esperando datos ");
  if(kbhit()==true)  //esperamos el primer caracter
  {
  let1=getc();  //lo guardamos en la variable
  delay_ms(200);
  usb_task();
  usb_cdc_putc(let1);  //y la mandamos por usb
  delay_ms(300);
  }
  }
 }whiLe (TRUE);


}



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