main.c

MEGA8做的USB下载线avrusb-20081126

/* Name: main.c
 * Project: custom-class, a basic USB example
 * Author: Christian Starkjohann
 * Creation Date: 2008-04-09
 * Tabsize: 4
 * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
 * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
 * This Revision: $Id: main.c 692 2008-11-07 15:07:40Z cs $
 */

/*
This example should run on most AVRs with only little changes. No special
hardware resources except INT0 are used. You may have to change usbconfig.h for
different I/O pins for USB. Please note that USB D+ must be the INT0 pin, or
at least be connected to INT0 as well.
We assume that an LED is connected to port B bit 0. If you connect it to a
different port or bit, change the macros below:
*/
#define LED_PORT_DDR        DDRB
#define LED_PORT_OUTPUT     PORTB
#define LED_BIT             0

#include <avr/io.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>  /* for sei() */
#include <util/delay.h>     /* for _delay_ms() */

#include <avr/pgmspace.h>   /* required by usbdrv.h */
#include "usbdrv.h"
#include "oddebug.h"        /* This is also an example for using debug macros */
#include "requests.h"       /* The custom request numbers we use */

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

usbMsgLen_t usbFunctionSetup(uchar data[8])
{
usbRequest_t    *rq = (void *)data;
static uchar    dataBuffer[4];  /* buffer must stay valid when usbFunctionSetup returns */

    if(rq->bRequest == CUSTOM_RQ_ECHO){ /* echo -- used for reliability tests */
        dataBuffer[0] = rq->wValue.bytes[0];
        dataBuffer[1] = rq->wValue.bytes[1];
        dataBuffer[2] = rq->wIndex.bytes[0];
        dataBuffer[3] = rq->wIndex.bytes[1];
        usbMsgPtr = dataBuffer;         /* tell the driver which data to return */
        return 4;
    }else if(rq->bRequest == CUSTOM_RQ_SET_STATUS){
        if(rq->wValue.bytes[0] & 1){    /* set LED */
            LED_PORT_OUTPUT |= _BV(LED_BIT);
        }else{                          /* clear LED */
            LED_PORT_OUTPUT &= ~_BV(LED_BIT);
        }
    }else if(rq->bRequest == CUSTOM_RQ_GET_STATUS){
        dataBuffer[0] = ((LED_PORT_OUTPUT & _BV(LED_BIT)) != 0);
        usbMsgPtr = dataBuffer;         /* tell the driver which data to return */
        return 1;                       /* tell the driver to send 1 byte */
    }
    return 0;   /* default for not implemented requests: return no data back to host */
}

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

int main(void)
{
uchar   i;

    wdt_enable(WDTO_1S);
    /* Even if you don't use the watchdog, turn it off here. On newer devices,
     * the status of the watchdog (on/off, period) is PRESERVED OVER RESET!
     */
    DBG1(0x00, 0, 0);       /* debug output: main starts */
    /* RESET status: all port bits are inputs without pull-up.
     * That's the way we need D+ and D-. Therefore we don't need any
     * additional hardware initialization.
     */
    odDebugInit();
    usbInit();
    usbDeviceDisconnect();  /* enforce re-enumeration, do this while interrupts are disabled! */
    i = 0;
    while(--i){             /* fake USB disconnect for > 250 ms */
        wdt_reset();
        _delay_ms(1);
    }
    usbDeviceConnect();
    LED_PORT_DDR |= _BV(LED_BIT);   /* make the LED bit an output */
    sei();
    DBG1(0x01, 0, 0);       /* debug output: main loop starts */
    for(;;){                /* main event loop */
        DBG1(0x02, 0, 0);   /* debug output: main loop iterates */
        wdt_reset();
        usbPoll();
    }
    return 0;
}

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