/* file "watch.c"
 *	Reads the PowerPC Time Base Facility on Excimer and prints out a twenty
 * 	second count to the terminal emulator.    Chuck Corley  981214
 */
#include <stdlib.h>
#include "Excimer.h"	/* File of Excimer board-specific constants */
#include "Exercise.h"	/* File of common typedefs */

#define printf dink_printf /* Enables Dynamic Fuct. So you can print to dink */

double dtime();		/* Given bus freq, returns time in seconds. */
unsigned long get_HID1();  /* Returns HID1 register. */
int main()
{
	double begin_time, current_time, delta_time = 0.0, seconds = 0.0;
	int int_seconds;
	unsigned long HID1_Reg;

	set_up_transfer_base(); /* Capture the dink transfer table address
				   enabling the ability to printf  */

	printf("PowerPC Timer Test.\n");
	printf("Beginning a twenty second count assuming bus speed of 66.67MHz.\n");
	printf("Please time me.\n");
	printf("If your stopwatch time differs significantly from 20 seconds, \n");
	printf("we can compute the actual bus speed.\n");
	begin_time = dtime();
	for (int_seconds = -1; int_seconds <= 20; int_seconds++) /*Countup to start.*/
	{
		while (delta_time < 1.0)
		{ 
			current_time = dtime();
			delta_time = current_time - (int_seconds) - begin_time;
		}
		delta_time = 0.0;
		switch (int_seconds)
		{
			case -1 :
				break;		/* Delay to get stopwatch ready. */
			case 0 :
				printf("Start now!\n");  /* Begin timing at zero seconds. */
				break;
			case 1:
				printf("%d second\n", int_seconds);
				break;
			default:
				printf("%d seconds\n", int_seconds);
		}	/* End of int_seconds switch  */				
	};
	printf("If your time was not 20 seconds,\n");
	printf("bus speed is (20 / your_time) * 66.67MHz.\n");

/* Bonus Exercise.  Given the bus speed, calculate the processor (core) speed.*/
	HID1_Reg = get_HID1() >> 28;     /* Move HID1[0:3] to [28:31] */
	printf("HID1 indicates PLL_CFG=%x.\n", HID1_Reg );
	printf("If bus=%dMHz, ", IBUS_MHz);
	switch (HID1_Reg)
	{
		case 0x4:  /*  PLL_CFG = 0b0100  */
			printf("Core Freq(2x)=%dMHz & ", 2*IBUS_MHz);
			printf("VCO Freq(2x)=%dMHz\n", 2*IBUS_MHz);
			break;
		case 0x5:  /*  PLL_CFG = 0b0101  */
			printf("Core Freq(2x)=%dMHz & ", 2*IBUS_MHz);
			printf("VCO Freq(4x)=%dMHz\n", 4*IBUS_MHz);
			break;
		case 0x6:  /*  PLL_CFG = 0b0110  */
			printf("Core Freq(2.5x)=%dMHz & ", (int)(2.5*(float)IBUS_MHz));
			printf("VCO Freq(2x)=%dMHz\n", 5*IBUS_MHz);
			break;
		case 0x8:  /*  PLL_CFG = 0b1000  */
			printf("Core Freq(3x)=%dMHz & ", 3*IBUS_MHz);
			printf("VCO Freq(2x)=%dMHz\n", 6*IBUS_MHz);
			break;
		case 0xe:  /*  PLL_CFG = 0b1110  */
			printf("Core Freq(3.5x)=%dMHz & ",(int)(3.5*(float)IBUS_MHz));
			printf("VCO Freq(2x)=%dMHz\n", 7*IBUS_MHz);
			break;
		case 0xa:  /*  PLL_CFG = 0b1010  */
			printf("Core Freq(4x)=%dMHz & ", 4*IBUS_MHz);
			printf("VCO Freq(2x)=%dMHz\n", 8*IBUS_MHz);
			break;
		case 0x7:  /*  PLL_CFG = 0b0111  */
			printf("Core Freq(4.5x)=%dMHz & ",(int)(4.5*(float)IBUS_MHz));
			printf("VCO Freq(2x)=%dMHz\n", 9*IBUS_MHz);
			break;
		case 0xb:  /*  PLL_CFG = 0b1011  */
			printf("Core Freq(5x)=%dMHz & ", 5*IBUS_MHz);
			printf("VCO Freq(2x)=%dMHz\n", 10*IBUS_MHz);
			break;
		case 0x9:  /*  PLL_CFG = 0b1001  */
			printf("Core Freq(5.5x)=%dMHz & ",(int)(5.5*(float)IBUS_MHz));
			printf("VCO Freq(2x)=%dMHz\n", 11*IBUS_MHz);
			break;
		case 0xd:  /*  PLL_CFG = 0b1101  */
			printf("Core Freq(6x)=%dMHz & ", 6*IBUS_MHz);
			printf("VCO Freq(2x)=%dMHz\n", 12*IBUS_MHz);
			break;
		case 0x3:  /*  PLL_CFG = 0b0011  */
			printf("PLL in bypass!\n");
			break;
		case 0xf:  /*  PLL_CFG = 0b0011  */
			printf("CLOCK OFF! How can this be???\n");
			break;
		default:
			printf("ERROR - INVALID PLL_CFG!");
	}	/* End of HID1 switch  */				
return 0;
}