//Modified to automatically test 74181 ALU functions

//Simple program to show display lower 8 pins, output from AX2 TinyFPGA, in terminal window
//Also takes input from terminal and applies to upper 8 pins of the AX2 connection
//See here for more info:  http://www.rayslogic.com/TinyFPGA/TinyFPGA_To_P2Eval.htm



#include "Platform.h"

//struct TTL74181_type {
//	uint8_t A;
//	uint8_t B;
//	uint8_t S;
//	uint8_t CN;
//	uint8_t M;
//} TTL74181;

int A, B, S, CN, M, F, CN4;



static void TTL74181_update()
{//modified version of this:  https://github.com/mamedev/historic-mame/blob/master/src/emu/machine/74181.c
	//TTL74181_state* c = &chips[which];
	//int A, B, S, CN, M;
	//A = TTL74181.A;
	//B = TTL74181.B;
	//S = TTL74181.S;
	//CN= TTL74181.CN;
	//M = TTL74181.M;


	uint8_t a0 = A & 1;
	uint8_t a1 = (A >> 1) & 1;
	uint8_t a2 = (A >> 2) & 1;
	uint8_t a3 = (A >> 3) & 1;

	uint8_t b0 = B & 1;
	uint8_t b1 = (B >> 1) & 1;
	uint8_t b2 = (B >> 2) & 1;
	uint8_t b3 = (B >> 3) & 1;

	uint8_t s0 = S & 1;
	uint8_t s1 = (S >> 1) & 1;
	uint8_t s2 = (S >> 2) & 1;
	uint8_t s3 = (S >> 3) & 1;

	//printf("A=%X\n", (a3 << 3) + (a2 << 2) + 1(a1 << 2) + a0);

	uint8_t cp = CN&1;
	uint8_t mp = (~M)&1;

	uint8_t ap0 = !(a0 | (b0 & s0) | (s1 & !b0));
	uint8_t bp0 = !((!b0 & s2 & a0) | (a0 & b0 & s3));
	uint8_t ap1 = !(a1 | (b1 & s0) | (s1 & !b1));
	uint8_t bp1 = !((!b1 & s2 & a1) | (a1 & b1 & s3));
	uint8_t ap2 = !(a2 | (b2 & s0) | (s1 & !b2));
	uint8_t bp2 = !((!b2 & s2 & a2) | (a2 & b2 & s3));
	uint8_t ap3 = !(a3 | (b3 & s0) | (s1 & !b3));
	uint8_t bp3 = !((!b3 & s2 & a3) | (a3 & b3 & s3));

	uint8_t fp0 = !(cp & mp) ^ (!ap0 & bp0);
	uint8_t fp1 = (!((mp & ap0) | (mp & bp0 & cp))) ^ (!ap1 & bp1);
	uint8_t fp2 = (!((mp & ap1) | (mp & ap0 & bp1) | (mp & cp & bp0 & bp1))) ^ (!ap2 & bp2);
	uint8_t fp3 = (!((mp & ap2) | (mp & ap1 & bp2) | (mp & ap0 & bp1 & bp2) | (mp & cp & bp0 & bp1 & bp2))) ^ (!ap3 & bp3);

	uint8_t aeqb = fp0 & fp1 & fp2 & fp3;
	uint8_t pp = !(bp0 & bp1 & bp2 & bp3);
	uint8_t gp = !((ap0 & bp1 & bp2 & bp3) | (ap1 & bp2 & bp3) | (ap2 & bp3) | ap3);
	//uint8_t cn4 = (!(cp & bp0 & bp1 & bp2 & bp3)) | gp;
	uint8_t cn4 = ((cp & bp0 & bp1 & bp2 & bp3)) | (!gp);  //RJA

	//printf("%d %d %d %d %d %d %d, %d %d\n", cn4, cp, bp0, bp1, bp2, bp3, gp, (cp & bp0 & bp1 & bp2 & bp3), !(cp & bp0 & bp1 & bp2 & bp3));
	//for (;;) {}

	//c->outputs[TTL74181_OUTPUT_F0] = fp0;
	//c->outputs[TTL74181_OUTPUT_F1] = fp1;
	//c->outputs[TTL74181_OUTPUT_F2] = fp2;
	//c->outputs[TTL74181_OUTPUT_F3] = fp3;
	//c->outputs[TTL74181_OUTPUT_AEQB] = aeqb;
	//c->outputs[TTL74181_OUTPUT_P] = pp;
	//c->outputs[TTL74181_OUTPUT_G] = gp;
	//c->outputs[TTL74181_OUTPUT_CN4] = cn4;
	F = (fp3 << 3) + (fp2 << 2)+(fp1 << 1)+(fp0);
	CN4 = (cn4 == 0) ? 0 : 1;

}


int main()
{
	//Show P2 clock freq at startup
	int cf = _clockfreq();
	printf("clock freq= %d\n", cf);

	int basepin = 0;
	char cHighPins[9];
	char cLowPins[9];
	cHighPins[8] = 0; //null terminate string
	cLowPins[8] = 0; //null terminate string

	//InteractiveTest();

	bool bPass = true;
	S = 15;
	printf("Beginning test with S=%X\n", S);
	CN = 0;
	M = 0;
	for (CN=0;CN<2;CN++)
		for (M=0;M<2;M++)
		{
			_pinw(basepin + 7, CN);
			_pinw(basepin + 6, M);
			_waitms(1000);
			printf("\n");
			for (A = 0; A < 16; A++)
				for (B = 0; B < 16; B++)
				{

					//Apply input to upper 8 pins of connection
					uint8_t input = (B<<4)+A;  //B on upper pins, A on lower pins
					for (int i = 0; i < 8; i++)
					{

						_pinw(basepin + 8 + i, (input >> i) & 1);

					}

					TTL74181_update();

			
			
					//Get all 16 pin states
					for (int i = 0; i < 8; i++)
					{//Get high and low pin input states
						//Low 8 pins (AX2 output)
						if (_pinr(basepin + i) == 0)
							cLowPins[7 - i] = '0';
						else
							cLowPins[7 - i] = '1';
						//High 8 pins (AX2 input)
						if (_pinr(basepin + i + 8) == 0)
							cHighPins[7 - i] = '0';
						else
							cHighPins[7 - i] = '1';
					}
			
					//Calculate fpga's F
			
					int ffpga = (_pinr(basepin + 3) << 3) + (_pinr(basepin + 2) << 2) + (_pinr(basepin + 1) << 1) + _pinr(basepin);
					int cn4fpga = (_pinr(basepin + 4)==0) ? 1 : 0;


					printf("M=%d, CN=%d, A=%X, B=%X, F(p2)=%X, F(fpga)=%X, CN4(p2)=%d, CN4(fpga)=%d\n", M, CN, A, B, F, ffpga, CN4, cn4fpga);// , cLowPins);
					_waitms(10);
					if (F != ffpga)
						bPass = false;
					if (M == 0)
						if (CN4 != cn4fpga)
							bPass = false;


					////Get all 16 pin states
					//for (int i = 0; i < 8; i++)
					//{//Get high and low pin input states
					//	//Low 8 pins (AX2 output)
					//	if (_pinr(basepin + i) == 0)
					//		cLowPins[7 - i] = '0';
					//	else
					//		cLowPins[7 - i] = '1';
					//	//High 8 pins (AX2 input)
					//	if (_pinr(basepin + i + 8) == 0)
					//		cHighPins[7 - i] = '0';
					//	else
					//		cHighPins[7 - i] = '1';
					//}
					////printf(" -->input= %c\n", cin);

					////show all 16pin states in high to low order
					////user input is applied to upper pins and AX2 output is on lower pins
					//printf("pins =%s_%s\n", cHighPins, cLowPins);

					//for (;;) {}

				}
		}

	if (bPass == true)
		printf("\nFPGA Passes test!\n");
	else
		printf("\nFPGA Fails test.\n");

		
}


void InteractiveTest()
{
	int basepin = 0;
	char cHighPins[9];
	char cLowPins[9];
	cHighPins[8] = 0; //null terminate string
	cLowPins[8] = 0; //null terminate string

	for (;;)
	{//Show pin states when key pressed in terminal window
		
		//get input, if any, from terminal
		printf("\nEnter HEX input for AX2 (or enter for none) >");
		uint8_t input=0;
		char cin=0;
		while (cin != '\n')
		{//get HEX input until enter pressed
			cin = getchar();
			int value = -1;
			if ((cin >= '0') && (cin <= '9'))
				value=cin-'0';
			if ((cin >= 'a') && (cin <= 'f'))
				value = cin - 'a'+10;
			if ((cin >= 'A') && (cin <= 'F'))
				value = cin - 'A' + 10;			
			if (value>=0)
				input = (input << 4)+value;
		}
		printf("input= %X\n", input);
		

		//Apply input to upper 8 pins of connection
		for (int i = 0; i < 8; i++)
		{

			_pinw(basepin+8+i,(input >> i) & 1);

		}
		//wait a bit
		_waitus(10);

		//Get all 16 pin states
		for (int i = 0; i < 8; i++)
		{//Get high and low pin input states
			//Low 8 pins (AX2 output)
			if (_pinr(basepin + i) == 0)
				cLowPins[7-i] = '0';
			else
				cLowPins[7-i] = '1';
			//High 8 pins (AX2 input)
			if (_pinr(basepin + i+8) == 0)
				cHighPins[7 - i] = '0';
			else
				cHighPins[7 - i] = '1';
		}
		//printf(" -->input= %c\n", cin);

		//show all 16pin states in high to low order
		//user input is applied to upper pins and AX2 output is on lower pins
		printf("pins =%s_%s\n", cHighPins,cLowPins);

	}

	


}