CatsEyes - Cat5/6 network cable tester

main.c

///////////////////////////////////////////////////////////////////////////////
//
// CatsEyes - 29/08/2010
// Cat5/6 network cable tester with 3 operating modes: Slow, fast and manual
//
// LEDs connected on P1.0 - P1.7 (red) and P2.7 (green)
// Momentary switches on RST and P2.6
//
// Gareth Williams // SquareDisk // All round, different
//

#include "msp430g2211.h"

void next_led(void);

volatile int ticks = 0;						// counts the WDT interrupts
volatile char mode = 0;						// 0 = slow, 1 = fast, 2 = manual
volatile int debounce = 2000;			// disables the buttons until WDT decreases this to 0

int main (void)
{
	WDTCTL = WDTPW + WDTHOLD;				// stop the watchdog timer

	// set up the clocks for the factory preset 1MHz
	BCSCTL1 = CALBC1_1MHZ;
	DCOCTL = CALDCO_1MHZ;

	// enable P1.0 to P1.7 as outputs
	P1DIR = BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
	P1OUT = BIT0;										// flip LED1 on, all others off
	P1SEL = 0;

	P2DIR = BIT7;										// enable P2.7 as an output
	P2OUT &= ~BIT7;									// make sure P2.7 is off
	P2SEL &= ~BIT7;

	// set up the interrupt for the button
	P2IE |= BIT6;
	P2IES |= BIT6;
	P2IFG &= ~BIT6;									// clear the interrupt flag

	// Enable NMI function of the RST pin
	// WDTTMSEL = Interval timer mode
	// clock source is SMCLK (1MHz or 1000000Hz)
	// Interval is clock /64 (15625 interrupts per second)
	WDTCTL = WDTPW + WDTNMI + WDTTMSEL + WDTCNTCL + WDTIS1 + WDTIS0;

	IE1 |= WDTIE + NMIIE;						// enable WDT and NMI interrupts

	_bis_SR_register(LPM1_bits + GIE);	// enter low power mode w/ interrupts
}

void next_led(void)
{
	switch (P1OUT)
	{
		case 0:												// start from the LED1
			P1OUT = BIT0;
			P2OUT = 0;
			break;
		case BIT7:										// turn on LED9, the green/shield test
			P1OUT = 0;
			P2OUT = BIT7;
			break;
		default:											// shift the bit left one digit to light the next red LED
			P1OUT = P1OUT << 1;
	}
}

#pragma vector=WDT_VECTOR
__interrupt void wdt_trigger(void)
{
	// WDT is triggered 15625 times per second
	ticks++;
	if (debounce > 0)
	{
		debounce--;
	}
	switch (mode)
	{
		case 0:
			if (ticks == 15635)
			{
				next_led();
				ticks = 0;
			}
			break;
		case 1:
			if (ticks == 5000)
			{
				next_led();
				ticks = 0;
			}
			break;
	}
}

#pragma vector=NMI_VECTOR
__interrupt void nmi_trigger(void)
{
//	WDTCTL = WDTPW + WDTNMI;
	if (debounce == 0)
	{
		mode = ++mode % 3;							// cycle the mode counter
		ticks = 0;
		debounce = 2000;
	}

	IFG1 &= ~NMIIFG;								// clear the NMI interrupt flag
	IE1 |= NMIIE;
}

#pragma vector=PORT2_VECTOR
__interrupt void button_trigger(void)
{
	next_led();
	P2IFG &= ~BIT6;									// clear the interrupt flag
}