main.c

利用ATtiny45晶片自行開發製做遊戲控制器

/* Name: main.c
 * Project: Thermostat based on AVR USB driver
 * Author: Christian Starkjohann
 * Creation Date: 2006-04-23
 * Tabsize: 4
 * Copyright: (c) 2006 by OBJECTIVE DEVELOPMENT Software GmbH
 * License: Proprietary, free under certain conditions. See Documentation.
 * This Revision: $Id: main.c 362 2007-06-25 14:38:21Z cs $
 */

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

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

/*
Pin assignment:


PB0, PB2 = USB data lines
*/

#define BIT_LED 4
#define BIT_KEY 1


#define UTIL_BIN4(x)        (uchar)((0##x & 01000)/64 + (0##x & 0100)/16 + (0##x & 010)/4 + (0##x & 1))
#define UTIL_BIN8(hi, lo)   (uchar)(UTIL_BIN4(hi) * 16 + UTIL_BIN4(lo))

#ifndef NULL
#define NULL    ((void *)0)
#endif

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

static uchar    reportBuffer[1];    /* buffer for HID reports */
static uchar    idleRate;           /* in 4 ms units */


static uchar    FlagKey;

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




PROGMEM char usbHidReportDescriptor[USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH] = {

    0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)
    0x15, 0x00,                    // LOGICAL_MINIMUM (0)
    0x09, 0x04,                    // USAGE (Joystick)
    0xa1, 0x01,                    // COLLECTION (Application)
    0x05, 0x09,                    //   USAGE_PAGE (Button)
    0x19, 0x01,                    //   USAGE_MINIMUM (Button 1)
    0x29, 0x08,                    //   USAGE_MAXIMUM (Button 8)
    0x15, 0x00,                    //   LOGICAL_MINIMUM (0)
    0x25, 0x01,                    //   LOGICAL_MAXIMUM (1)
    0x75, 0x01,                    //   REPORT_SIZE (1)
    0x95, 0x08,                    //   REPORT_COUNT (8)
    0x55, 0x00,                    //   UNIT_EXPONENT (0)
    0x65, 0x00,                    //   UNIT (None)
    0x81, 0x02,                    //   INPUT (Data,Var,Abs)
    0xc0                           // END_COLLECTION
};



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


static void timerPoll(void)
{
static uchar timerCnt;
static uchar i;

    if(TIFR & (1 << TOV1)){
        TIFR = (1 << TOV1); /* clear overflow */
        if(++timerCnt >= 63){       /* ~ 1 second interval */
		    timerCnt = 0;
			if (!FlagKey) {
				FlagKey = 1;
				
				if (++i > 3)
					i=0;
				switch (i) {
					case 0:
						reportBuffer[0] = 1;    /* no modifiers */
						
						break;
					case 1:
						reportBuffer[0] = 2;    /* no modifiers */
						
						break;
					case 2:
						reportBuffer[0] = 8;    /* no modifiers */
						
						break;
					case 3:
						reportBuffer[0] = 64;    /* no modifiers */
						
						break;
				}
			
			}			
        }
    }
}
/* ------------------------------------------------------------------------- */

static void timerInit(void)
{
    TCCR1 = 0x0b;           /* select clock: 16.5M/1k -> overflow rate = 16.5M/256k = 62.94 Hz */
}


/* ------------------------------------------------------------------------- */
/* ------------------------ interface to USB driver ------------------------ */
/* ------------------------------------------------------------------------- */

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 */
            reportBuffer[0] = 0;    /* no modifiers */
			
            return sizeof(reportBuffer);
        }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{
        /* no vendor specific requests implemented */
    }
	return 0;
}

/* ------------------------------------------------------------------------- */
/* --------------------------------- main ---------------------------------- */
/* ------------------------------------------------------------------------- */

int main(void)
{
uchar    i;

/* Calibrate the RC oscillator to 8.25 MHz. The core clock of 16.5 MHz is
 * derived from the 66 MHz peripheral clock by dividing. We assume that the
 * EEPROM contains a calibration value in location 0. If no calibration value
 * has been stored during programming, we offset Atmel's 8 MHz calibration
 * value according to the clock vs OSCCAL diagram in the data sheet. This
 * seems to be sufficiently precise (<= 1%).
 */
    uchar calibrationValue = eeprom_read_byte(0);
    if(calibrationValue != 0xff){
        OSCCAL = calibrationValue;  /* a calibration value is supplied */
    }else{
        /* we have no calibration value, assume 8 MHz calibration and adjust from there */
        if(OSCCAL < 125){
            OSCCAL += 3;    /* should be 3.5 */
        }else if(OSCCAL >= 128){
            OSCCAL += 7;    /* should be 7 */
        }else{  /* must be between 125 and 128 */
            OSCCAL = 127;   /* maximum possible avoiding discontinuity */
        }
    }
    odDebugInit();
    DDRB = (1 << USB_CFG_DMINUS_BIT) | (1 << USB_CFG_DPLUS_BIT);
    PORTB = 0;          /* indicate USB disconnect to host */
    for(i=0;i<20;i++){  /* 300 ms disconnect, also allows our oscillator to stabilize */
        _delay_ms(15);
    }
    DDRB = 1 << BIT_LED;    /* output for LED */
    PORTB = 1 << BIT_KEY;   /* pull-up on key input */
    wdt_enable(WDTO_1S);
    timerInit();
    usbInit();
    sei();
    for(;;){    /* main event loop */
        wdt_reset();
        usbPoll();
        if(usbInterruptIsReady() ){ /* we can send another key */
         
            usbSetInterrupt(reportBuffer, sizeof(reportBuffer));
            FlagKey = 0;
        }
        timerPoll();
    }
    return 0;
}