MyCpu/GAL/Rom0/ROM0.PLD at main · fortinsylvain/MyCpu · GitHub

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Name            ROM0;
Partno          1;
Revision        01;
Date            5/20/25;
Designer        Sylvain Fortin;
Company         Home;
Location        Montreal;
Assembly        Example;
Device          g16v8;

/****************************************************************/
/* ROM LUT                                                      */
/* Inputs:  C3, C2, C1, C0, PHI2                                */
/* Outputs: I_N, RW, DIR, G_N, AL, AH, UL, UH                   */
/****************************************************************/
/** Inputs **/
PIN 3 = A;  // PHI2
PIN 4 = B;  // C0
PIN 5 = C;  // C1
PIN 6 = D;  // C2
PIN 7 = E;  // C3

/** Outputs **/
PIN 12 = I_N;
PIN 13 = RW;
PIN 14 = DIR;
PIN 15 = G_N;
PIN 16 = AL;
PIN 17 = AH;
PIN 18 = UL;
PIN 19 = UH;

/** Field Declarations **/
FIELD Address = [E, D, C, B, A];
FIELD OutputBits = [UH, UL, AH, AL, G_N, DIR, RW, I_N];  // 8-bit output

/** Table Mapping **/
TABLE Address => OutputBits {
'b'00000 => 'b'00001011;	// REG -> UH
'b'00001 => 'b'10001011;
'b'00010 => 'b'00001011;	// REG -> UL
'b'00011 => 'b'01001011;
'b'00100 => 'b'00001011;	// REG -> AH
'b'00101 => 'b'00101011;
'b'00110 => 'b'00001011;	// REG -> AL
'b'00111 => 'b'00011011;
'b'01000 => 'b'00000011;	// DATA -> REG
'b'01001 => 'b'00000011;
'b'01010 => 'b'00001010;	// u<7:0> -> REG
'b'01011 => 'b'00001010;
'b'01100 => 'b'00001010;	// u<7:0> -> uH
'b'01101 => 'b'10001010;
'b'01110 => 'b'00001010;	// u<7:0> -> uL
'b'01111 => 'b'01001010;
'b'10000 => 'b'00001011;	// R -> ALU B -> Q
'b'10001 => 'b'00001011;
'b'10010 => 'b'00001011;	// A -> Q
'b'10011 => 'b'00001011;
'b'10100 => 'b'00001011;	// REG -> A
'b'10101 => 'b'00001011;
'b'10110 => 'b'00000101;	// REG -> DATA
'b'10111 => 'b'00000101;
'b'11000 => 'b'00001011;	// Q -> REG
'b'11001 => 'b'00001011;
'b'11010 => 'b'00001010;	// u<7:0> -> AL
'b'11011 => 'b'00011010;
'b'11100 => 'b'00001011;	// Qn -> A
'b'11101 => 'b'00001011;
'b'11110 => 'b'00001010;	// u<7:0> -> AH
'b'11111 => 'b'00101010;
}