main.c

同为电脑遥控器

//redKontroll version 1.0  fredrikolofsson.com
//GNU GPL v2 - See the OBDEV license for further details.  (http://www.obdev.at/avrusb/)

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

#include "usbdrv.h"

static void hardwareInit(void) {
	
	//--set pins to output
	DDRB= 0b00110000;						//output pins for shiftin
	DDRD= 0b00000101;						//output pins for usb
	
	//--internal pull-ups for inputs
	PORTD= 0b11111010;
	PORTB= 0b00001111;
	
	//--setup adc
	//ADCSRA |= (1<<ADPS0);					//prescale 2
	//ADCSRA |= (1<<ADPS1);					//prescale 4
	ADCSRA |= (1<<ADPS2);					//prescale 16
	//ADCSRA |= ((1<<ADPS2)|(1<<ADPS0));	//prescale 32
	ADCSRA |= (1<<ADEN);					//enable adc
	
	//--reset usb
	uchar i= 20;
	while(i) {								//300ms
		_delay_ms(15);
		i--;
	}
	DDRD= 0;
}

static uchar reportBuffer[8];				/* buffer for HID reports */
static uchar idleRate;						/* in 4 ms units */
uchar changed= 0;
uchar shiftIn(void);
uchar encoderIn(uchar currPin, uchar lastPin, uchar a, uchar b);

PROGMEM char usbHidReportDescriptor[USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH] = { //USB report descriptor
	0x05, 0x01,        // USAGE_PAGE (Generic Desktop)
	0x09, 0x04,        // USAGE (Joystick)
	0xa1, 0x01,        // COLLECTION (Application)
	
	0x09, 0x30,        // USAGE (shift)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x31,        // USAGE (enc0)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x32,        // USAGE (enc1)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x33,        // USAGE (enc2)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x34,        // USAGE (enc3)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x35,        // USAGE (enc4)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x36,        // USAGE (pot0)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0x09, 0x37,        // USAGE (pot1)
	0x15, 0x00,        // LOGICAL_MINIMUM (0)
	0x26, 0xff, 0x00,  // LOGICAL_MAXIMUM (255)
	0x75, 0x08,        // REPORT_SIZE (8)
	0x95, 0x01,        // REPORT_COUNT (1)
	0x81, 0x02,        // INPUT (Data,Var,Abs)
	
	0xc0               // END_COLLECTION
};

static void buildReport(uchar shift, uchar enc0, uchar enc1, uchar enc2, uchar enc3, uchar enc4, uchar pot0, uchar pot1) {
	reportBuffer[0]= shift;
	reportBuffer[1]= enc0;
	reportBuffer[2]= enc1;
	reportBuffer[3]= enc2;
	reportBuffer[4]= enc3;
	reportBuffer[5]= enc4;
	reportBuffer[6]= pot0;
	reportBuffer[7]= pot1;
}

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 */
            buildReport(0, 0, 0, 0, 0, 0, 0, 0);
            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;
}

int main(void) {
	
	uchar shift= 0, lastShift= 0;
	uchar lastPINB= PINB&0b00001111;
	uchar lastPIND= PIND&0b11111010;
	uchar enc0= 0, enc1= 0, enc2= 0, enc3= 0, enc4= 0, encTemp;
	uchar pot0= 0, pot1= 0;
	
	wdt_enable(WDTO_2S);
	hardwareInit();
	usbInit();
	sei();
	
	//--main loop
	while(1) {
		
		wdt_reset();
		usbPoll();
		
		//--read digital inputs
		shift= shiftIn();
		if(shift!=lastShift) {
			changed= 1;
			lastShift= shift;
		}
		
		//--read encoders
		encTemp= encoderIn(PIND&0b11111010, lastPIND, 1, 3);
		if(encTemp==1) {
			enc0--;
			changed= 2;
			lastPIND= PIND&0b11111010;
		} else if(encTemp==2) {
			enc0++;
			changed= 2;
			lastPIND= PIND&0b11111010;
		}
		encTemp= encoderIn(PIND&0b11111010, lastPIND, 4, 5);
		if(encTemp==1) {
			enc1--;
			changed= 2;
			lastPIND= PIND&0b11111010;
		} else if(encTemp==2) {
			enc1++;
			changed= 2;
			lastPIND= PIND&0b11111010;
		}
		encTemp= encoderIn(PIND&0b11111010, lastPIND, 6, 7);
		if(encTemp==1) {
			enc2--;
			changed= 2;
			lastPIND= PIND&0b11111010;
		} else if(encTemp==2) {
			enc2++;
			changed= 2;
			lastPIND= PIND&0b11111010;
		}
		encTemp= encoderIn(PINB&0b00001111, lastPINB, 0, 1);
		if(encTemp==1) {
			enc3--;
			changed= 3;
			lastPINB= PINB&0b00001111;
		} else if(encTemp==2) {
			enc3++;
			changed= 3;
			lastPINB= PINB&0b00001111;
		}
		encTemp= encoderIn(PINB&0b00001111, lastPINB, 2, 3);
		if(encTemp==1) {
			enc4--;
			changed= 3;
			lastPINB= PINB&0b00001111;
		} else if(encTemp==2) {
			enc4++;
			changed= 3;
			lastPINB= PINB&0b00001111;
		}
		
		//--read softpots
		ADMUX= 0b11000010;			//select adc channel 2
		ADCSRA |= (1<<ADSC);		//start conversion
		while((ADCSRA&64)==64);		//wait for ADSC bit to go low
		pot0= ADCL>>2;				//skip 2 lowest bits
		pot0 |= (ADCH<<6);
		if(reportBuffer[6]!=pot0) {
			changed= 4;
		}
		ADMUX= 0b11000001;			//select adc channel 1
		ADCSRA |= (1<<ADSC);		//start conversion
		while((ADCSRA&64)==64);		//wait for ADSC bit to go low
		pot1= ADCL>>2;				//skip 2 lowest bits
		pot1 |= (ADCH<<6);
		if(reportBuffer[7]!=pot1) {
			changed= 4;
		}
		
		//--send report
		if(usbInterruptIsReady()&&(changed>0)) {
			buildReport(shift, enc0, enc1, enc2, enc3, enc4, pot0, pot1);
			usbSetInterrupt(reportBuffer, sizeof(reportBuffer));
			changed= 0;
		}
	}
	return 0;
}

uchar encoderIn(uchar currPin, uchar lastPin, uchar a, uchar b) {
	if((lastPin&(1<<a))!=(1<<a) && ((currPin&(1<<a))==(1<<a))) {
		if((currPin&(1<<b))!=(1<<b)) {
			return 2;
		}
		return 1;
	} else if((lastPin&(1<<a))==(1<<a) && ((currPin&(1<<a))!=(1<<a))) {
		if((currPin&(1<<b))==(1<<b)) {
			return 2;
		}
		return 1;
	}
	return 0;
}

uchar shiftIn(void) {
	char i;
	uchar data= 0;
	PORTB |= (1<<5);					//set latch pin to collect parallel data
	_delay_us(20);
	PORTB &= ~(1<<5);					//clear latch pin to transmit
	for(i= 7; i>=0; i--) {
		PORTB &= ~(1<<4);				//clear clock pin
		if((PINC&(1<<0)) == (1<<0)) {
			data |= (1<<i);
		}
		PORTB |= (1<<4);				//set clock pin
	}
	return data;
}