Code:

/* Name: main.c
 * Project: HID-Test
 * Author: Christian Starkjohann
 * Creation Date: 2006-02-02
 * Tabsize: 4
 * Copyright: (c) 2006 by OBJECTIVE DEVELOPMENT Software GmbH
 * License: GNU GPL v2 (see License.txt) or proprietary (CommercialLicense.txt)
 * This Revision: $Id: main.c 299 2007-03-29 17:07:19Z cs $
 */

#define F_CPU   12000000L    /* evaluation board runs on 4MHz */

#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include <avr/wdt.h>

#include "usbdrv.h"
#include "oddebug.h"

/* ----------------------- hardware I/O abstraction ------------------------ */

/* pin assignments:

PB1   Key 1
PB2   Key 2
PB3   Key 3
PB4   Key 4

PD0   USB-
PD1   debug tx
PD2   USB+ (int0)
PD6   Key Shift
*/

static void hardwareInit(void)
{
uchar   i, j;

    PORTB = 0xff;   /* activate all pull-ups */
    DDRB = 1;       /* all pins input */
    PORTD = 0xfa;   /* 1111 1010 bin: activate pull-ups except on USB lines */
    DDRD = 0x07;    /* 0000 0111 bin: all pins input except USB (-> USB reset) */
   j = 0;
   while(--j){     /* USB Reset by device only required on Watchdog Reset */
      i = 0;
      while(--i); /* delay >10ms for USB reset */
   }

    DDRD = 0x02;    /* 0000 0010 bin: remove USB reset condition */
    /* configure timer 0 for a rate of 12M/(1024 * 256) = 45.78 Hz (~22ms) */
    TCCR0 = 5;      /* timer 0 prescaler: 1024 */
}

/* ------------------------------------------------------------------------- */

#define NUM_KEYS    8

static uchar    keyPressed(void)
{
uchar   i, mask, x, key;
   
   key = 0;
    x = PINB;
    mask = 1;
    for(i=0;i<6;i++){
        if((x & mask) == 0)
            key = i;
        mask <<= 1;
    }
    
    x = PIND;
    mask = 64;
        if((x & mask) == 0 && key > 0)
            key = key + 4;
    return key;
}

/* ------------------------------------------------------------------------- */
/* ----------------------------- USB interface ----------------------------- */
/* ------------------------------------------------------------------------- */

static uchar    idleRate;           /* in 4 ms units */
static uchar    protocolVer=1;      /* 0 is the boot protocol, 1 is report protocol */

char usbHidReportDescriptor[USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH] 
  PROGMEM = {
    0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)
    0x09, 0x06,                    // USAGE (Keyboard)
    0xa1, 0x01,                    // COLLECTION (Application)
    0x05, 0x07,                    //   USAGE_PAGE (Keyboard)
    0x19, 0xe0,                    //   USAGE_MINIMUM (Keyboard LeftControl)
    0x29, 0xe7,                    //   USAGE_MAXIMUM (Keyboard Right GUI)
    0x15, 0x00,                    //   LOGICAL_MINIMUM (0)
    0x25, 0x01,                    //   LOGICAL_MAXIMUM (1)
    0x75, 0x01,                    //   REPORT_SIZE (1)
    0x95, 0x08,                    //   REPORT_COUNT (8)
    0x81, 0x02,                    //   INPUT (Data,Var,Abs)
    0x95, 0x01,                    //   REPORT_COUNT (1)
    0x75, 0x08,                    //   REPORT_SIZE (8)
    0x81, 0x03,                    //   INPUT (Cnst,Var,Abs)
    0x95, 0x05,                    //   REPORT_COUNT (5)
    0x75, 0x01,                    //   REPORT_SIZE (1)
    0x05, 0x08,                    //   USAGE_PAGE (LEDs)
    0x19, 0x01,                    //   USAGE_MINIMUM (Num Lock)
    0x29, 0x05,                    //   USAGE_MAXIMUM (Kana)
    0x91, 0x02,                    //   OUTPUT (Data,Var,Abs)
    0x95, 0x01,                    //   REPORT_COUNT (1)
    0x75, 0x03,                    //   REPORT_SIZE (3)
    0x91, 0x03,                    //   OUTPUT (Cnst,Var,Abs)
    0x95, 0x06,                    //   REPORT_COUNT (6)
    0x75, 0x08,                    //   REPORT_SIZE (8)
    0x15, 0x00,                    //   LOGICAL_MINIMUM (0)
    0x25, 0x65,                    //   LOGICAL_MAXIMUM (101)
    0x05, 0x07,                    //   USAGE_PAGE (Keyboard)
    0x19, 0x00,                    //   USAGE_MINIMUM (Reserved (no event indicated))
    0x29, 0x65,                    //   USAGE_MAXIMUM (Keyboard Application)
    0x81, 0x00,                    //   INPUT (Data,Ary,Abs)
    0xc0                           // END_COLLECTION  
};

#define KEY_A       4

static uchar reportBuffer[NUM_KEYS];

static void buildReport(uchar key)
{
    int i;
    reportBuffer[0] = 0;
    reportBuffer[1] = 0;
   for(i=2;i<=NUM_KEYS;i++)
   {
      if(key==0){reportBuffer[i] = 0;}
      else{ reportBuffer[i] = KEY_A+i;}
    }                         
}

uchar   usbFunctionSetup(uchar data[8]){
   usbRequest_t    *rq = (void *)data;
   usbMsgPtr = reportBuffer;
    if((rq->bmRequestType & USBRQ_TYPE_MASK) == USBRQ_TYPE_CLASS){    /* class request type */
        if(rq->bRequest == USBRQ_HID_GET_REPORT){  /* wValue: ReportType (highbyte), ReportID (lowbyte) */
            /* we only have one report type, so don't look at wValue */
            return sizeof(reportBuffer);
        }else if(rq->bRequest == USBRQ_HID_SET_REPORT){
            if (rq->wLength.word == 1) { /* We expect one byte reports */
           return 0xFF; /* Call usbFunctionWrite with data */
            }  
       }else if(rq->bRequest == USBRQ_HID_GET_IDLE){
            usbMsgPtr = &idleRate;
            return 1;
        }else if(rq->bRequest == USBRQ_HID_SET_IDLE){
            idleRate = rq->wValue.bytes[1];
        }else if(rq->bRequest == USBRQ_HID_GET_PROTOCOL) {
            if (rq->wValue.bytes[1] < 1) {
              protocolVer = rq->wValue.bytes[1];
            }
        }else if(rq->bRequest == USBRQ_HID_SET_PROTOCOL) {
         usbMsgPtr = &protocolVer;
         return 1;
       }
    }
   return 0;
}

uchar usbFunctionWrite(uchar *data, uchar len) {
   return 0x01;
}


/* ------------------------------------------------------------------------- */

int   main(void)
{
uchar   key, lastKey = 0, keyDidChange = 0;
uchar   idleCounter = 0;

   wdt_enable(WDTO_2S);
   hardwareInit();
   odDebugInit();
   usbInit();
   sei();
   DBG1(0x00, 0, 0);
   for(;;){   /* main event loop */
      wdt_reset();
      usbPoll();
        key = keyPressed();
        if(lastKey != key){
            lastKey = key;
            keyDidChange = 1;
        }
        if(TIFR & (1<<TOV0)){   /* 22 ms timer */
            TIFR = 1<<TOV0;
            if(idleRate != 0){
                if(idleCounter > 4){
                    idleCounter -= 5;   /* 22 ms in units of 4 ms */
                }else{
                    idleCounter = idleRate;
                    keyDidChange = 1;
                }
            }
        }
        if(keyDidChange && usbInterruptIsReady()){
            keyDidChange = 0;
            /* use last key and not current key status in order to avoid lost
               changes in key status. */
            buildReport(lastKey);
            usbSetInterrupt(reportBuffer, sizeof(reportBuffer));
        }
   }
   return 0;
}

/* ------------------------------------------------------------------------- */

Code:

/* Name: usbconfig.h
 * Project: AVR USB driver
 * Author: Christian Starkjohann
 * Creation Date: 2005-04-01
 * Tabsize: 4
 * Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH
 * License: GNU GPL v2 (see License.txt) or proprietary (CommercialLicense.txt)
 * This Revision: $Id: usbconfig.h 300 2007-03-29 17:07:35Z cs $
 */

#ifndef __usbconfig_h_included__
#define __usbconfig_h_included__

/*
General Description:
This file contains parts of the USB driver which can be configured and can or
must be adapted to your hardware.

Please note that the usbdrv contains a usbconfig-prototype.h file now. We
recommend that you use that file as a template because it will always list
the newest features and options.
*/

/* ---------------------------- Hardware Config ---------------------------- */

#define USB_CFG_IOPORTNAME      D
/* This is the port where the USB bus is connected. When you configure it to
 * "B", the registers PORTB, PINB and DDRB will be used.
 */
#define USB_CFG_DMINUS_BIT      0
/* This is the bit number in USB_CFG_IOPORT where the USB D- line is connected.
 * This may be any bit in the port.
 */
#define USB_CFG_DPLUS_BIT       2
/* This is the bit number in USB_CFG_IOPORT where the USB D+ line is connected.
 * This may be any bit in the port. Please note that D+ must also be connected
 * to interrupt pin INT0!
 */

/* ----------------------- Optional Hardware Config ------------------------ */

/* #define USB_CFG_PULLUP_IOPORTNAME   D */
/* If you connect the 1.5k pullup resistor from D- to a port pin instead of
 * V+, you can connect and disconnect the device from firmware by calling
 * the macros usbDeviceConnect() and usbDeviceDisconnect() (see usbdrv.h).
 * This constant defines the port on which the pullup resistor is connected.
 */
/* #define USB_CFG_PULLUP_BIT          4 */
/* This constant defines the bit number in USB_CFG_PULLUP_IOPORT (defined
 * above) where the 1.5k pullup resistor is connected. See description
 * above for details.
 */

/* --------------------------- Functional Range ---------------------------- */

#define USB_CFG_HAVE_INTRIN_ENDPOINT    1
/* Define this to 1 if you want to compile a version with two endpoints: The
 * default control endpoint 0 and an interrupt-in endpoint 1.
 */
#define USB_CFG_HAVE_INTRIN_ENDPOINT3   0
/* Define this to 1 if you want to compile a version with three endpoints: The
 * default control endpoint 0, an interrupt-in endpoint 1 and an interrupt-in
 * endpoint 3. You must also enable endpoint 1 above.
 */
#define USB_CFG_IMPLEMENT_HALT          0
/* Define this to 1 if you also want to implement the ENDPOINT_HALT feature
 * for endpoint 1 (interrupt endpoint). Although you may not need this feature,
 * it is required by the standard. We have made it a config option because it
 * bloats the code considerably.
 */
#define USB_CFG_INTR_POLL_INTERVAL      10
/* If you compile a version with endpoint 1 (interrupt-in), this is the poll
 * interval. The value is in milliseconds and must not be less than 10 ms for
 * low speed devices.
 */
#define USB_CFG_IS_SELF_POWERED         0
/* Define this to 1 if the device has its own power supply. Set it to 0 if the
 * device is powered from the USB bus.
 */
#define USB_CFG_MAX_BUS_POWER           100
/* Set this variable to the maximum USB bus power consumption of your device.
 * The value is in milliamperes. [It will be divided by two since USB
 * communicates power requirements in units of 2 mA.]
 */
#define USB_CFG_IMPLEMENT_FN_WRITE      1
/* Set this to 1 if you want usbFunctionWrite() to be called for control-out
 * transfers. Set it to 0 if you don't need it and want to save a couple of
 * bytes.
 */
#define USB_CFG_IMPLEMENT_FN_READ       0
/* Set this to 1 if you need to send control replies which are generated
 * "on the fly" when usbFunctionRead() is called. If you only want to send
 * data from a static buffer, set it to 0 and return the data from
 * usbFunctionSetup(). This saves a couple of bytes.
 */
#define USB_CFG_IMPLEMENT_FN_WRITEOUT   0
/* Define this to 1 if you want to use interrupt-out (or bulk out) endpoint 1.
 * You must implement the function usbFunctionWriteOut() which receives all
 * interrupt/bulk data sent to endpoint 1.
 */
#define USB_CFG_HAVE_FLOWCONTROL        0
/* Define this to 1 if you want flowcontrol over USB data. See the definition
 * of the macros usbDisableAllRequests() and usbEnableAllRequests() in
 * usbdrv.h.
 */

/* -------------------------- Device Description --------------------------- */

/* We cannot use Obdev's free shared VID/PID pair because this is a HID.
 * We use John Hyde's VID (author of the book "USB Design By Example") for
 * this example instead. John has offered this VID for use by students for
 * non-commercial devices. Well... This example is for demonstration and
 * education only... DO NOT LET DEVICES WITH THIS VID ESCAPE YOUR LAB!
 * The Product-ID is a random number.
 */
#define  USB_CFG_VENDOR_ID       0x42, 0x42
/* USB vendor ID for the device, low byte first. If you have registered your
 * own Vendor ID, define it here. Otherwise you use obdev's free shared
 * VID/PID pair. Be sure to read USBID-License.txt for rules!
 */
#define  USB_CFG_DEVICE_ID       0x31, 0xe1
/* This is the ID of the product, low byte first. It is interpreted in the
 * scope of the vendor ID. If you have registered your own VID with usb.org
 * or if you have licensed a PID from somebody else, define it here. Otherwise
 * you use obdev's free shared VID/PID pair. Be sure to read the rules in
 * USBID-License.txt!
 */
#define USB_CFG_DEVICE_VERSION  0x03, 0x01
/* Version number of the device: Minor number first, then major number.
 */
#define USB_CFG_VENDOR_NAME     'M'
#define USB_CFG_VENDOR_NAME_LEN 1
/* These two values define the vendor name returned by the USB device. The name
 * must be given as a list of characters under single quotes. The characters
 * are interpreted as Unicode (UTF-16) entities.
 * If you don't want a vendor name string, undefine these macros.
 * ALWAYS define a vendor name containing your Internet domain name if you use
 * obdev's free shared VID/PID pair. See the file USBID-License.txt for
 * details. 
 */
#define USB_CFG_DEVICE_NAME     'S'
#define USB_CFG_DEVICE_NAME_LEN 1
/* Same as above for the device name. If you don't want a device name, undefine
 * the macros. See the file USBID-License.txt before you assign a name.
 */
#define USB_CFG_SERIAL_NUMBER   '2'
#define USB_CFG_SERIAL_NUMBER_LEN   1
/* Same as above for the serial number. If you don't want a serial number,
 * undefine the macros.
 * It may be useful to provide the serial number through other means than at
 * compile time. See the section about descriptor properties below for how
 * to fine tune control over USB descriptors such as the string descriptor
 * for the serial number.
 */
#define USB_CFG_DEVICE_CLASS    0   /* specify the class at the interface level */
#define USB_CFG_DEVICE_SUBCLASS 0
/* See USB specification if you want to conform to an existing device class.
 */
#define USB_CFG_INTERFACE_CLASS     0x03    /* HID class */
#define USB_CFG_INTERFACE_SUBCLASS  0x01    /* Boot-device subclass */
#define USB_CFG_INTERFACE_PROTOCOL  0x01    /* Keyboard protocol */
/* See USB specification if you want to conform to an existing device class or
 * protocol.
 */
#define USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH    63  /* total length of report descriptor */
/* Define this to the length of the HID report descriptor, if you implement
 * an HID device. Otherwise don't define it or define it to 0.
 */

/* ------------------- Fine Control over USB Descriptors ------------------- */
/* If you don't want to use the driver's default USB descriptors, you can
 * provide our own. These can be provided as (1) fixed length static data in
 * flash memory, (2) fixed length static data in RAM or (3) dynamically at
 * runtime in the function usbFunctionDescriptor(). See usbdrv.h for more
 * information about this function.
 * Descriptor handling is configured through the descriptor's properties. If
 * no properties are defined or if they are 0, the default descriptor is used.
 * Possible properties are:
 *   + USB_PROP_IS_DYNAMIC: The data for the descriptor should be fetched
 *     at runtime via usbFunctionDescriptor().
 *   + USB_PROP_IS_RAM: The data returned by usbFunctionDescriptor() or found
 *     in static memory is in RAM, not in flash memory.
 *   + USB_PROP_LENGTH(len): If the data is in static memory (RAM or flash),
 *     the driver must know the descriptor's length. The descriptor itself is
 *     found at the address of a well known identifier (see below).
 * List of static descriptor names (must be declared PROGMEM if in flash):
 *   char usbDescriptorDevice[];
 *   char usbDescriptorConfiguration[];
 *   char usbDescriptorHidReport[];
 *   char usbDescriptorString0[];
 *   int usbDescriptorStringVendor[];
 *   int usbDescriptorStringDevice[];
 *   int usbDescriptorStringSerialNumber[];
 * Other descriptors can't be provided statically, they must be provided
 * dynamically at runtime.
 *
 * Descriptor properties are or-ed or added together, e.g.:
 * #define USB_CFG_DESCR_PROPS_DEVICE   (USB_PROP_IS_RAM | USB_PROP_LENGTH(18))
 *
 * The following descriptors are defined:
 *   USB_CFG_DESCR_PROPS_DEVICE
 *   USB_CFG_DESCR_PROPS_CONFIGURATION
 *   USB_CFG_DESCR_PROPS_STRINGS
 *   USB_CFG_DESCR_PROPS_STRING_0
 *   USB_CFG_DESCR_PROPS_STRING_VENDOR
 *   USB_CFG_DESCR_PROPS_STRING_PRODUCT
 *   USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER
 *   USB_CFG_DESCR_PROPS_HID
 *   USB_CFG_DESCR_PROPS_HID_REPORT
 *   USB_CFG_DESCR_PROPS_UNKNOWN (for all descriptors not handled by the driver)
 *
 */

#define USB_CFG_DESCR_PROPS_DEVICE                  0
#define USB_CFG_DESCR_PROPS_CONFIGURATION           0
#define USB_CFG_DESCR_PROPS_STRINGS                 0
#define USB_CFG_DESCR_PROPS_STRING_0                0
#define USB_CFG_DESCR_PROPS_STRING_VENDOR           0
#define USB_CFG_DESCR_PROPS_STRING_PRODUCT          0
#define USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER    0
#define USB_CFG_DESCR_PROPS_HID                     0
#define USB_CFG_DESCR_PROPS_HID_REPORT              0
#define USB_CFG_DESCR_PROPS_UNKNOWN                 0

/* ----------------------- Optional MCU Description ------------------------ */

/* The following configurations have working defaults in usbdrv.h. You
 * usually don't need to set them explicitly. Only if you want to run
 * the driver on a device which is not yet supported or with a compiler
 * which is not fully supported (such as IAR C) or if you use a differnt
 * interrupt than INT0, you may have to define some of these.
 */
/* #define USB_INTR_CFG            MCUCR */
/* #define USB_INTR_CFG_SET        ((1 << ISC00) | (1 << ISC01)) */
/* #define USB_INTR_CFG_CLR        0 */
/* #define USB_INTR_ENABLE         GIMSK */
/* #define USB_INTR_ENABLE_BIT     INT0 */
/* #define USB_INTR_PENDING        GIFR */
/* #define USB_INTR_PENDING_BIT    INTF0 */

#endif /* __usbconfig_h_included__ */