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[/] [t6507lp/] [trunk/] [fv/] [alu_chk.e] - Diff between revs 234 and 235

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Rev 234	Rev 235
Line 78...	Line 78...

`case inst.input_kind {`	`case inst.input_kind {`
`ENABLED_VALID: {`	`ENABLED_VALID: {`
`//out("CYCLE ", count_cycles, ": executing and comparing");`	`//out("CYCLE ", count_cycles, ": executing and comparing");`
`execute(inst.alu_opcode);`	`execute(inst.alu_opcode);`

`if (reg_status[3:3] == 1) {`
`case inst.alu_opcode {`
`SBC_IMM: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_ZPG: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_ZPX: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_ABS: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_ABX: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_ABY: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_IDX: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`SBC_IDY: {`
`reg_a = alu_result;`
`reg_result = alu_result;`
`reg_status = alu_status;`
`};`
`};`
`};`
`};`	`};`
`RESET: {`	`RESET: {`
`reg_x = 0;`	`reg_x = 0;`
`reg_y = 0;`	`reg_y = 0;`
`reg_status = 8'b00100010;`	`reg_status = 8'b00100010;`
`reg_a = 0; // TODO: check this`	`reg_a = 0;`
`reg_result = 0;`	`reg_result = 0;`

`return;`	`return;`
`};`	`};`
`ENABLED_RAND: {`	`ENABLED_RAND: {`
Line 409...	Line 364...
`update_z(dest);`	`update_z(dest);`
`update_n(dest);`	`update_n(dest);`
`};`	`};`

`exec_sub() is {`	`exec_sub() is {`
`if (reg_status[3:3] == 1) { // decimal`
`var op1 : int;`
`var op2 : int;`

`warning("EXECUTING SBC DECIMAL! IGNORING RESULT!");`

`//out("i am subtracting ", reg_a, " and ", inst.alu_a, " carry is ", reg_status[0:0]);`

`op1 = inst.alu_a[3:0];`
`op2 = inst.alu_a[7:4];`

`op1 = reg_a[3:0] - op1 -1 + reg_status[0:0];`
`op2 = reg_a[7:4] - op2;`

`if (op1 >= 10) {`
`op2 = op2 + op1/10;`
`op1 = op1 % 10;`
`} else if (op1 < 0) {`
`op2 = op2 - op1/10;`
`op1 = -(op1 % 10);`
`};`

`reg_status[0:0] = 1;`

`if (op2 >= 10) {`
`op2 = op2 % 10;`
`}`
`else if (op2 < 0) {`
`op2 = op2 + 10;`
`reg_status[0:0] = 0;`
`};`

`reg_result[3:0] = op1;`
`reg_result[7:4] = op2;`

`update_n(reg_result);`
`update_z(reg_result);`
`update_v(reg_a, inst.alu_a, reg_result);`
`reg_a = reg_result;`
`}`
`else {`
`var temp: int;`	`var temp: int;`

`temp = reg_a - inst.alu_a - 1 + reg_status[0:0];`	`temp = reg_a - inst.alu_a - 1 + reg_status[0:0];`
`reg_result = reg_a - inst.alu_a - 1 + reg_status[0:0];`	`reg_result = reg_a - inst.alu_a - 1 + reg_status[0:0];`

`reg_status[7:7] = temp[7:7]; // N`	`reg_status[7:7] = temp[7:7]; // N`
`//print (reg_a ^ inst.alu_a) & (reg_a ^ temp) & 0x80;`	`//print (reg_a ^ inst.alu_a) & (reg_a ^ temp) & 0x80;`
`reg_status[6:6] = (reg_a[7:7] ^ inst.alu_a[7:7]) & (reg_a[7:7] ^ temp[7:7]); // V`	`reg_status[6:6] = (reg_a[7:7] ^ inst.alu_a[7:7]) & (reg_a[7:7] ^ temp[7:7]); // V`

	`print reg_result;`
`if (reg_result == 0) {`	`if (reg_result == 0) {`
`reg_status[1:1] = 1; // Z`	`reg_status[1:1] = 1; // Z`
`} else {`	`} else {`
`reg_status[1:1] = 0; // Z`	`reg_status[1:1] = 0; // Z`
`};`	`};`

`reg_a = temp.as_a(byte);`	`if (reg_status[3:3] == 1) { // decimal`
	`var op1 : int;`
	`var op2 : int;`

	`op1 = (reg_a & 0x0f ) - (inst.alu_a & 0x0f) - ( (reg_status[0:0] == 1) ? 0 : 1);`
	`print op1;`
	`op2 = (reg_a & 0xf0) - (inst.alu_a & 0xf0);`
	`print op2;`

	`if (op1[4:4] == 1) {`
	`op1 -= 6;`
	`op2 = op2 - 1;`
	`};`
	`print op1;`
	`print op2;`

	`if(op2[8:8] == 1) {`
	`op2 -= 0x60;`
	`};`
	`print op2;`

`//print (temp & 0xff00);`	`reg_a = (op1 & 0x0f) \| (op2 & 0xf0);`
`//print (temp & 0xff00) != 0x0000;`	`reg_result = reg_a;`
	`}`
	`else {`
	`reg_a = temp.as_a(byte);`
	`};`

`if ( (temp & 0xff00) != 0x0000 ) {`	`if ( (temp & 0xff00) != 0x0000 ) {`
`reg_status[0:0] = 0;`	`reg_status[0:0] = 0;`
`} else {`	`} else {`
`reg_status[0:0] = 1;`	`reg_status[0:0] = 1;`
`}`

`};`	`};`
`};`	`};`

`exec_rot(left : bool, arg1 : byte) is {`	`exec_rot(left : bool, arg1 : byte) is {`
`var oldcarry : bit;`	`var oldcarry : bit;`
Line 598...	Line 534...
`if (reg_status[3:3] == 1) {`	`if (reg_status[3:3] == 1) {`
`var op1 : byte;`	`var op1 : byte;`
`var op2 : byte;`	`var op2 : byte;`
`var aux : byte;`	`var aux : byte;`

`//out("i am adding ", reg_a, " and ", inst.alu_a, " carry is ", reg_status[0:0]);`

`op1 = reg_a[3:0] + inst.alu_a[3:0] + reg_status[0:0];`	`op1 = reg_a[3:0] + inst.alu_a[3:0] + reg_status[0:0];`
`print op1;`
`//Int32 lo = (A & 0x0f) + (operand & 0x0f) + (C ? 1 : 0);`	`//Int32 lo = (A & 0x0f) + (operand & 0x0f) + (C ? 1 : 0);`

`op2 = reg_a[7:4] + inst.alu_a[7:4];`	`op2 = reg_a[7:4] + inst.alu_a[7:4];`
`//carry_aux = reg_a[7:4] + inst.alu_a[7:4];`	`//carry_aux = reg_a[7:4] + inst.alu_a[7:4];`
`print op2;`
`//Int32 hi = (A & 0xf0) + (operand & 0xf0);`	`//Int32 hi = (A & 0xf0) + (operand & 0xf0);`

`aux = op1 + op2;`	`aux = op1 + op2;`

`if (aux[7:0] == 0) {`	`if (aux[7:0] == 0) {`
Line 629...	Line 561...
`reg_status[7:7] = op2[3:3];`	`reg_status[7:7] = op2[3:3];`
`//N = hi & 0x80;`	`//N = hi & 0x80;`

`reg_status[6:6] = ~(reg_a[7:7] ^ inst.alu_a[7:7]) & (reg_a[7:7] ^ op2[3:3]); // V`	`reg_status[6:6] = ~(reg_a[7:7] ^ inst.alu_a[7:7]) & (reg_a[7:7] ^ op2[3:3]); // V`
`//V = ~(A ^ operand) & (A ^ hi) & 0x80;`	`//V = ~(A ^ operand) & (A ^ hi) & 0x80;`
`print op2;`
`if (op2 > 0x09) {`	`if (op2 > 0x09) {`
`op2 += 0x06;`	`op2 += 0x06;`
`print op2;`
`};`	`};`
`//if (hi > 0x90) hi += 0x60;`	`//if (hi > 0x90) hi += 0x60;`

`reg_status[0:0] = (op2 > 15) ? 1 : 0;`	`reg_status[0:0] = (op2 > 15) ? 1 : 0;`
`//C = hi & 0xff00;`	`//C = hi & 0xff00;`

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[/] [t6507lp/] [trunk/] [fv/] [alu_chk.e] - Diff between revs 234 and 235