jb302@28: /* iset.c
jb302@28:  * IR functions */
jb302@28: #include <stdlib.h>
jb302@28: #include "iset.h"
jb302@28: #include "mem.h"
jb302@28: 
jb302@28: /* useful macros */
jb302@28: #define NNN (IR & 0x07)
jb302@28: #define MMM ((IR & 0x38) >> 3)
jb302@28: 
jb302@28: /* 0x00 - NOP */
jb302@28: void
jb302@28: NOP(void) {    
jb302@28: }
jb302@28: 
jb302@28: /* 0x08 - SET C
jb302@28:  * 0x0A - SET BS
jb302@28:  * 0x0C - SET IE */
jb302@28: void
jb302@28: SET(void) {
jb302@28:     switch (IR) {
jb302@28:         
jb302@28:         case 0x08:
jb302@29:             set_flag(C, 0x01);
jb302@28:             break;
jb302@28:         
jb302@28:         case 0x0A:
jb302@29:             set_flag(BS, 0x01);
jb302@28:             break;
jb302@28:         
jb302@28:         case 0x0C:
jb302@29:             set_flag(IE, 0x01);
jb302@28:             break;
jb302@28:         
jb302@28:         default:
jb302@28:             break;
jb302@28:     }
jb302@28: }
jb302@28: 
jb302@28: /* 0x09 - CLR C
jb302@28:  * 0x0B - CLR BS
jb302@28:  * 0x0D - CLR IE */
jb302@28: void
jb302@28: CLR(void) {
jb302@28:     switch (IR) {
jb302@28:         
jb302@28:         case 0x09:
jb302@29:             set_flag(C, 0x00);
jb302@28:             break;
jb302@28:         
jb302@28:         case 0x0B:
jb302@29:             set_flag(BS, 0x00);
jb302@28:             break;
jb302@28:         
jb302@28:         case 0x0D:
jb302@29:             set_flag(IE, 0x00);
jb302@28:             break;
jb302@28:         
jb302@28:         default:
jb302@28:             break;
jb302@28:     }    
jb302@28: }
jb302@28: 
jb302@28: /* 0x0E - CPL C
jb302@28:  * 0x0F - CPL A */
jb302@28: void
jb302@28: CPL(void) {
jb302@28:     switch (IR) {
jb302@28:         
jb302@28:         case 0x0E:
jb302@29:             if (get_flag(C) == 0) {
jb302@29:                 set_flag(C, 0x01);
jb302@28:             }
jb302@28:             else {
jb302@29:                 set_flag(C, 0x00);
jb302@28:             }
jb302@28:         
jb302@28:         case 0x0F:
jb302@28:             A = ~A;
jb302@28:             break;
jb302@28:         
jb302@28:         default:
jb302@28:             break;
jb302@28:     }
jb302@28: }
jb302@28: 
jb302@28: /* 0x10 - XCSD */
jb302@28: void
jb302@28: XCSD(void) {
jb302@28:     tmpw = get_wide(SP);
jb302@28:     set_wide(SP, get_wide(DPTR));
jb302@28:     set_wide(DPTR, tmpw);
jb302@28: }
jb302@28: 
jb302@28: /* 0x11 - SFA */
jb302@28: void
jb302@28: SFA(void) {
jb302@28:     A = flags;
jb302@28: }
jb302@28: 
jb302@28: /* 0x12 - LAF */
jb302@28: void
jb302@28: LAF(void) {
jb302@28:     flags = A;   
jb302@28: }
jb302@28: 
jb302@28: /* 0b00010XXX - special MOVs
jb302@28:  * 0b00011XXX - direct, indirect and indexed MOVs
jb302@28:  * 0b00100nnn - register-indirect MOVs - MOV @DPTR, Rn
jb302@28:  * 0b00101nnn - immediate movs - MOV Rn, #data8
jb302@28:  * 0b00110nnn - MOV Rn, A
jb302@28:  * 0b00111nnn - MOV A, Rn
jb302@28:  * 0b01mmmnnn - 64 register move instructions
jb302@28:  *
jb302@28:  * this is a mess */
jb302@28: void
jb302@28: MOV(void) {
jb302@28:     switch (IR & 0x40) {
jb302@28:        
jb302@28:         case 0x00:
jb302@28:             switch (IR & 0xF8) {
jb302@28:                 
jb302@29:                 /* 0b00010XXX - special MOVs*/
jb302@28:                 case 0x10:
jb302@28:                     switch (NNN) {
jb302@28:                         
jb302@28:                         /* MOV DPTR, SP */
jb302@28:                         case 3:
jb302@28:                             set_wide(DPTR, get_wide(SP));
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV SP, DPTR */
jb302@28:                         case 4:
jb302@28:                             set_wide(SP, get_wide(DPTR));
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV A, #data8 */
jb302@28:                         case 5:
jb302@28:                             A = fetch();
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV SP, #data16 */
jb302@28:                         case 6:
jb302@28:                             set_wide(SP, fetch_wide());
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV DPTR, #data16 */
jb302@28:                         case 7:
jb302@28:                             set_wide(DPTR, fetch_wide());
jb302@28:                             break;
jb302@28:                         
jb302@28:                         default:
jb302@28:                             break;
jb302@28:                     }
jb302@28:                     break;
jb302@28:                 
jb302@29:                 /* 0b00011XXX - direct, indirect and indexed MOVs*/
jb302@28:                 case 0x18:
jb302@28:                     switch (NNN) {
jb302@28:                         
jb302@28:                         /* MOV A, addr16 */
jb302@28:                         case 0:
jb302@28:                             set_wide(TMP, fetch_wide());
jb302@28:                             A = mem[get_wide(TMP)];
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV addr16, A */
jb302@28:                         case 1:
jb302@28:                             set_wide(TMP, fetch_wide());
jb302@28:                             mem[get_wide(TMP)] = A;
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV A, @A+DPTR */
jb302@28:                         case 2:
jb302@29:                             set_wide(TMP, A + get_wide(DPTR));
jb302@29:                             A = mem[get_wide(TMP)];
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV A, @A+PC */
jb302@28:                         case 3:
jb302@29:                             set_wide(TMP, A + get_wide(PC));
jb302@29:                             A = mem[TMP];
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV A, @addr16 */
jb302@28:                         case 4:
jb302@28:                             set_wide(TMP, fetch_wide());
jb302@28:                             A = mem[mem[get_wide(TMP)]];
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV @addr16, A */ 
jb302@28:                         case 5:
jb302@28:                             set_wide(TMP, fetch_wide());
jb302@28:                             mem[mem[get_wide(TMP)]] = A;
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV A, @DPTR */
jb302@28:                         case 6:
jb302@29:                             set_wide(TMP, get_wide(DPTR));
jb302@29:                             A = mem[get_wide(TMP)];
jb302@28:                             break;
jb302@28:                         
jb302@28:                         /* MOV @DPTR, A */
jb302@28:                         case 7:
jb302@29:                             set_wide(TMP, get_wide(DPTR));
jb302@29:                             mem[get_wide(TMP)] = A;
jb302@28:                             break;
jb302@28:                         
jb302@28:                         default:
jb302@28:                             break;
jb302@28:                     }
jb302@28:                     break;
jb302@28:                 
jb302@29:                 /* 0b00100nnn - MOV @DPTR, Rn*/
jb302@28:                 case 0x20:
jb302@29:                     set_wide(TMP, get_wide(DPTR));
jb302@30:                     mem[get_wide(TMP)] = get_reg(NNN);
jb302@28:                     break;
jb302@28:                 
jb302@29:                 /* 0b00101nnn - immediate movs - MOV Rn, #data8*/
jb302@28:                 case 0x28:
jb302@29:                     set_reg(NNN, fetch());
jb302@28:                     break;
jb302@28:                 
jb302@29:                 /* 0b00110nnn - MOV Rn, A */
jb302@28:                 case 0x30:
jb302@29:                     set_reg(NNN, A);
jb302@28:                     break;
jb302@28:                 
jb302@30:                 /* 0b00111nnn MOV A, Rn */
jb302@28:                 case 0x38:
jb302@29:                     A = get_reg(NNN);
jb302@28:                     break;
jb302@28:                 
jb302@28:                 default:
jb302@28:                     break;
jb302@28:                 }
jb302@29:             break;;
jb302@28:         
jb302@30:         /* 0b01mmmnnn MOV Rm Rn
jb302@30:          *   if m == n: MOV Rm, @DPTR */
jb302@28:         case 0x40:
jb302@29:             if (NNN == MMM) {
jb302@29:                 set_wide(TMP, get_wide(DPTR));
jb302@29:                 set_reg(NNN, mem[get_wide(TMP)]);
jb302@29:             }
jb302@29:             else {
jb302@29:                 set_reg(MMM, get_reg(NNN));
jb302@29:             }
jb302@28:             break;
jb302@28:         
jb302@28:         default:
jb302@28:             break;
jb302@28:     }
jb302@28: }
jb302@28: 
jb302@30: 
jb302@30: /* 0x80 - ANL A, R0
jb302@30:  * 0x81 - ANL A, R1
jb302@30:  * 0x82 - ANL A, R2
jb302@30:  * 0x83 - ANL A, R3
jb302@30:  * 0x84 - ANL A, DPH
jb302@30:  * 0x85 - ANL A, DPL
jb302@30:  * 0x86 - ANL A, #data8
jb302@30:  * 0x87 - ANL A, @DPTR */
jb302@28: void
jb302@28: ANL(void) {
jb302@30:     if (NNN < 6) {
jb302@30:         A = A & get_reg(NNN);
jb302@30:     }
jb302@30:     else {
jb302@30:         switch (NNN) {
jb302@30:             
jb302@30:             case 6:
jb302@30:                 A = A & fetch();
jb302@30:                 break;
jb302@30: 
jb302@30:             case 7:
jb302@30:                 set_wide(TMP, get_wide(DPTR));
jb302@30:                 A = A & mem[TMP];
jb302@30:                 break;
jb302@30:         }
jb302@30:     }
jb302@30:     set_zp(A);
jb302@28: }
jb302@28: 
jb302@30: /* 0x88 - ORL A, R0
jb302@30:  * 0x89 - ORL A, R1
jb302@30:  * 0x8A - ORL A, R2
jb302@30:  * 0x8B - ORL A, R3
jb302@30:  * 0x8C - ORL A, DPH
jb302@30:  * 0x8D - ORL A, DPL
jb302@30:  * 0x8E - ORL A, #data8
jb302@30:  * 0x8F - ORL A, @DPTR */
jb302@28: void
jb302@28: ORL(void) {
jb302@30:     if (NNN < 6) {
jb302@30:         A = A | get_reg(NNN);
jb302@30:     }
jb302@30:     else {
jb302@30:         switch (NNN) {
jb302@30:             
jb302@30:             case 6:
jb302@30:                 A = A | fetch();
jb302@30:                 break;
jb302@30: 
jb302@30:             case 7:
jb302@30:                 set_wide(TMP, get_wide(DPTR));
jb302@30:                 A = A | mem[TMP];
jb302@30:                 break;
jb302@30:         }
jb302@30:     }
jb302@30:     set_zp(A);
jb302@28: }
jb302@28: 
jb302@30: /* 0x90 - XRL A, R0
jb302@30:  * 0x91 - XRL A, R1
jb302@30:  * 0x92 - XRL A, R2
jb302@30:  * 0x93 - XRL A, R3
jb302@30:  * 0x94 - XRL A, DPH
jb302@30:  * 0x95 - XRL A, DPL
jb302@30:  * 0x96 - XRL A, #data8
jb302@30:  * 0x97 - XRL A, @DPTR */
jb302@28: void
jb302@28: XRL(void) {
jb302@30:     if (NNN < 6) {
jb302@30:         A = A ^ get_reg(NNN);
jb302@30:     }
jb302@30:     else {
jb302@30:         switch (NNN) {
jb302@30:             
jb302@30:             case 6:
jb302@30:                 A = A ^ fetch();
jb302@30:                 break;
jb302@28: 
jb302@30:             case 7:
jb302@30:                 set_wide(TMP, get_wide(DPTR));
jb302@30:                 A = A ^ mem[TMP];
jb302@30:                 break;
jb302@30:         }
jb302@30:     }
jb302@30:     set_zp(A);
jb302@28: }
jb302@28: 
jb302@28: /* 0x98 - RL A */
jb302@28: void
jb302@28: RL(void) {
jb302@28:     A = (A << 1) | (A >> 7);
jb302@28: }
jb302@28: 
jb302@28: /* 0x99 - RLC A */
jb302@28: void
jb302@28: RLC(void) {
jb302@30:      tmpb = A;
jb302@30:      A = (A << 1) | get_flag(C);
jb302@30:      set_flag(C, tmpb >> 7);
jb302@28: }
jb302@28: 
jb302@28: /* 0x9A - RR A */
jb302@28: void
jb302@28: RR(void) {
jb302@28:     A = (A >> 1) | (A << 7);
jb302@28: }
jb302@28: 
jb302@28: /* 0x9B - RRC A */
jb302@28: void
jb302@28: RRC(void) { 
jb302@30:     tmpb = A;
jb302@30:     A = (A >> 1) | (get_flag(C) << 7);
jb302@30:     set_flag(C, tmpb & 0x01);
jb302@28: }
jb302@28: 
jb302@28: /* 0x9C - INC DPTR
jb302@28:  * 0x9E - INC A */
jb302@28: void
jb302@30: INC(void) {
jb302@30:     switch (IR) {
jb302@30: 
jb302@30:         case 0x9C:
jb302@30:             tmpw = get_wide(DPTR);
jb302@30:             if ((tmpw + 1) > 0xFFFF) {
jb302@30:                 set_flag(OV, 1);
jb302@30:             }
jb302@30:             set_wide(DPTR, tmpw + 1);
jb302@30:             set_zp(DPL);
jb302@30:             set_zp(DPH);
jb302@30:             break;
jb302@30: 
jb302@30:         case 0x9E:
jb302@30:             if ((A + 1) > 0xFF) {
jb302@30:                 set_flag(OV, 1);
jb302@30:             }
jb302@30:             A++;
jb302@30:             set_zp(A);
jb302@30: 
jb302@30:     }
jb302@28: }
jb302@28: 
jb302@28: /* 0x9D - DEC DPTR
jb302@28:  * 0x9F - DEC A */
jb302@28: void
jb302@28: DEC(void) {
jb302@30:     switch (IR) {
jb302@30: 
jb302@30:         case 0x9D:
jb302@30:             tmpw = get_wide(DPTR);
jb302@30:             if ((tmpw - 1) < 0) {
jb302@30:                 set_flag(OV, 1);
jb302@30:             }
jb302@30:             set_wide(DPTR, tmpw - 1);
jb302@30:             set_zp(DPL);
jb302@30:             set_zp(DPH);
jb302@30: 
jb302@30:         case 0x9F:
jb302@30:             if ((A - 1) < 0) {
jb302@30:                 set_flag(OV, 1);
jb302@30:             }
jb302@30:             A--;
jb302@30:             set_zp(A);
jb302@30:     }    
jb302@28: }
jb302@28: 
jb302@30: /* 0xA0 - ADD A, R0
jb302@30:  * 0xA1 - ADD A, R1
jb302@30:  * 0xA2 - ADD A, R2
jb302@30:  * 0xA3 - ADD A, R3
jb302@30:  * 0xA4 - ADD A, DPH
jb302@30:  * 0xA5 - ADD A, DPL
jb302@30:  * 0xA6 - ADD A, #data8
jb302@30:  * 0xA7 - ADD A, @DPTR */
jb302@28: void
jb302@28: ADD(void) {
jb302@30:     if (NNN < 6) {
jb302@31:         if ((A + get_reg(NNN)) > 0xFF) {
jb302@31:             set_flag(OV, 1);
jb302@31:         }
jb302@31:         else {
jb302@31:             set_flag(OV, 0);
jb302@30:         }
jb302@30:         A = A + get_reg(NNN);
jb302@30:         set_zp(A);
jb302@30:     }
jb302@30:     else {
jb302@30:         switch (NNN) {
jb302@30:             
jb302@30:             case 6:
jb302@31:                 tmpb = fetch();
jb302@31:                 if ((A + tmpb) > 0xFF) {
jb302@31:                     set_flag(OV, 1);
jb302@31:                 }
jb302@31:                 else {
jb302@31:                     set_flag(OV, 0);
jb302@31:                 }
jb302@31:                 A = A + tmpb;
jb302@30:                 set_zp(A);
jb302@30:                 break;
jb302@30: 
jb302@30:             case 7:
jb302@30:                 set_wide(TMP, get_wide(DPTR));
jb302@31:                 if ((A + mem[TMP]) > 0xFF) {
jb302@31:                     set_flag(OV, 1);
jb302@31:                 }
jb302@31:                 else {
jb302@31:                     set_flag(OV, 0);
jb302@31:                 }
jb302@30:                 A = A + mem[TMP];
jb302@30:                 set_zp(A);
jb302@30:                 break;
jb302@30:         }
jb302@30:     }
jb302@30: 
jb302@28: }
jb302@28: 
jb302@35: /* 0xA8 - ADDC A, R0
jb302@35:  * 0xA9 - ADDC A, R1
jb302@35:  * 0xAA - ADDC A, R2
jb302@35:  * 0xAB - ADDC A, R3
jb302@35:  * 0xAC - ADDC A, DPH
jb302@35:  * 0xAD - ADDC A, DPL
jb302@35:  * 0xAE - ADDC A, #data8
jb302@35:  * 0xAF - ADDC A, @DPTR */
jb302@28: void
jb302@28: ADDC(void) {
jb302@35:     if (NNN < 6) {
jb302@35:         if ((A + get_reg(NNN) + get_flag(C)) > 0xFF) {
jb302@35:             set_flag(C, 1);
jb302@35:         }
jb302@35:         else {
jb302@35:             set_flag(C, 0);
jb302@35:         }
jb302@35:         A = A + get_reg(NNN) + get_flag(C);
jb302@35:         set_zp(A);
jb302@35:     }
jb302@35:     else {
jb302@35:         switch (NNN) {
jb302@35:             
jb302@35:             case 6:
jb302@35:                 tmpb = fetch();
jb302@35:                 if ((A + tmpb + get_flag(C)) > 0xFF) {
jb302@35:                     set_flag(C, 1);
jb302@35:                 }
jb302@35:                 else {
jb302@35:                     set_flag(C, 0);
jb302@35:                 }
jb302@35:                 A = A + tmpb + get_flag(C);
jb302@35:                 set_zp(A);
jb302@35:                 break;
jb302@35: 
jb302@35:             case 7:
jb302@35:                 set_wide(TMP, get_wide(DPTR));
jb302@35:                 if ((A + mem[TMP] + get_flag(C)) > 0xFF) {
jb302@35:                     set_flag(C, 1);
jb302@35:                 }
jb302@35:                 else {
jb302@35:                     set_flag(C, 0);
jb302@35:                 }
jb302@35:                 A = A + mem[TMP] + get_flag(C);
jb302@35:                 set_zp(A);
jb302@35:                 break;
jb302@35:         }
jb302@35:     }
jb302@35: 
jb302@35: 
jb302@28: }
jb302@28: 
jb302@30: /* 0xB0 - SUB A, R0
jb302@30:  * 0xB1 - SUB A, R1
jb302@30:  * 0xB2 - SUB A, R2
jb302@30:  * 0xB3 - SUB A, R3
jb302@35:  * 0xB4 - SB A, DPH
jb302@30:  * 0xB5 - SUB A, DPL
jb302@30:  * 0xB6 - SUB A, #data8
jb302@30:  * 0xB7 - SUB A, @DPTR */
jb302@28: void
jb302@28: SUB(void) {
jb302@30:     if (NNN < 6) {
jb302@31:         if ((A - get_reg(NNN)) < 0){
jb302@34:             set_flag(S, 1);
jb302@31:         }
jb302@31:         else {
jb302@34:             set_flag(S, 0);
jb302@31:         }
jb302@30:         A = A - get_reg(NNN);
jb302@30:         set_zp(A);
jb302@30:     }
jb302@30:     else {
jb302@30:         switch (NNN) {
jb302@30:             
jb302@30:             case 6:
jb302@31:                 tmpb = fetch();
jb302@31:                 if ((A - tmpb) < 0) {
jb302@34:                     set_flag(S, 1);
jb302@31:                 }
jb302@31:                 else {
jb302@34:                     set_flag(S, 0);
jb302@31:                 }
jb302@31:                 A = A - tmpb;
jb302@30:                 set_zp(A);
jb302@30:                 break;
jb302@30: 
jb302@30:             case 7:
jb302@30:                 set_wide(TMP, get_wide(DPTR));
jb302@31:                 if ((A - mem[TMP]) < 0) {
jb302@34:                     set_flag(S, 1);
jb302@31:                 }
jb302@31:                 else {
jb302@34:                     set_flag(S, 0);
jb302@31:                 }
jb302@30:                 A = A - mem[TMP];
jb302@30:                 set_zp(A);
jb302@30:                 break;
jb302@30:         }
jb302@30:     }
jb302@28: }
jb302@28: 
jb302@35: /* 0xB8 - SUBB A, R0
jb302@35:  * 0xB9 - SUBB A, R1
jb302@35:  * 0xBA - SUBB A, R2
jb302@35:  * 0xBB - SUBB A, R3
jb302@35:  * 0xBC - SUBB A, DPH
jb302@35:  * 0xBD - SUBB A, DPL
jb302@35:  * 0xBE - SUBB A, #data8
jb302@35:  * 0xBF - SUBB A, @DPTR */
jb302@28: void
jb302@28: SUBB(void) {
jb302@35:     if (NNN < 6) {
jb302@35:         if ((A - get_reg(NNN) - get_flag(C)) < 0){
jb302@35:             set_flag(C, 1);
jb302@35:         }
jb302@35:         else {
jb302@35:             set_flag(C, 0);
jb302@35:         }
jb302@35:         A = A - get_reg(NNN) -get_flag(C);
jb302@35:         set_zp(A);
jb302@35:     }
jb302@35:     else {
jb302@35:         switch (NNN) {
jb302@35:             
jb302@35:             case 6:
jb302@35:                 tmpb = fetch();
jb302@35:                 if ((A - tmpb - get_flag(C)) < 0) {
jb302@35:                     set_flag(C, 1);
jb302@35:                 }
jb302@35:                 else {
jb302@35:                     set_flag(C, 0);
jb302@35:                 }
jb302@35:                 A = A - tmpb - get_flag(C);
jb302@35:                 set_zp(A);
jb302@35:                 break;
jb302@35: 
jb302@35:             case 7:
jb302@35:                 set_wide(TMP, get_wide(DPTR));
jb302@35:                 if ((A - mem[TMP] - get_flag(C)) < 0) {
jb302@35:                     set_flag(C, 1);
jb302@35:                 }
jb302@35:                 else {
jb302@35:                     set_flag(C, 0);
jb302@35:                 }
jb302@35:                 A = A - mem[TMP] - get_flag(C);
jb302@35:                 set_zp(A);
jb302@35:                 break;
jb302@35:         }
jb302@35:     }
jb302@28: }
jb302@28: 
jb302@28: void
jb302@28: PJMP(void) {
jb302@28:     /* implement me */
jb302@28: }
jb302@28: 
jb302@28: void
jb302@28: PCALL(void) {
jb302@28:     /* implement me */
jb302@28: }
jb302@28: 
jb302@28: /* 0xD0 - DJNZ R0, rel8
jb302@28:  * 0xD1 - DJNZ R1, rel8
jb302@28:  * 0xD2 - DJNZ R2, rel8
jb302@28:  * 0xD3 - DJNZ R3, rel8 */
jb302@28: void
jb302@28: DJNZ(void) {
jb302@35:     set_reg(NNN, get_reg(NNN) - 1);
jb302@35:     if (get_reg(NNN) == 0) {
jb302@35:         set_wide(PC, get_wide(PC) + (signed char)fetch() - 1);
jb302@35:     }
jb302@35:     else {
jb302@35:         inc_pc(1);
jb302@35:     }
jb302@28: }
jb302@28: 
jb302@35: /* 0xD4 - CJNE R0, #data, rel8
jb302@35:  * 0xD5 - CJNE R1, #data, rel8
jb302@35:  * 0xD6 - CJNE R2, #data, rel8
jb302@35:  * 0xD7 - CJNE R3, #data, rel8 
jb302@35:  * 0xDF - CJNE A, #data8, rel8 */
jb302@28: void
jb302@28: CJNE(void) {
jb302@35:     switch(IR) {
jb302@35:         
jb302@35:         case 0xDF:
jb302@35:              tmpb = fetch();
jb302@35:             if (tmpb != A) {
jb302@35:                 set_wide(PC, get_wide(PC) + (signed char)fetch() - 1);
jb302@35:             }
jb302@35:             else {
jb302@35:                 inc_pc(1);
jb302@35:             }
jb302@35:             break;
jb302@35: 
jb302@35: 
jb302@35:         default:
jb302@35:             tmpb = fetch();
jb302@35:             if (tmpb != get_reg(NNN - 4)) {
jb302@35:                 set_wide(PC, get_wide(PC) + (signed char)fetch() - 1);
jb302@35:             }
jb302@35:             else {
jb302@35:                 inc_pc(1);
jb302@35:             }
jb302@35:             break;
jb302@35:     }
jb302@28: }
jb302@28: 
jb302@28: /* 0xD8 - LJMP addr16 */
jb302@28: void
jb302@28: LJMP(void) {
jb302@35:     set_wide(PC, fetch_wide());
jb302@28: }
jb302@28: 
jb302@35: /* 0xD9 - LCALL addr16 */
jb302@28: void
jb302@28: LCALL(void) {
jb302@35:     /* push PC to stack */
jb302@35:     mem[get_wide(SP)] = get_reg(PCL);
jb302@35:     set_wide(SP, get_wide(SP) + 1);
jb302@35:     mem[get_wide(SP)] = get_reg(PCH);
jb302@35:     set_wide(SP, get_wide(SP) + 1);
jb302@35:     /* jmp */
jb302@35:     set_wide(PC, fetch_wide());
jb302@28: }
jb302@28: 
jb302@35: /* 0xDA - RET */
jb302@28: void
jb302@28: RET(void) {
jb302@35:     /* get PC from stack */
jb302@35:     set_wide(SP, get_wide(SP) - 1);
jb302@35:     tmpb = mem[get_wide(SP)]; /* PCH */
jb302@35:     set_wide(SP, get_wide(SP) - 1);
jb302@35:     set_wide(PC, MWIDE(tmpb, mem[get_wide(SP)]));
jb302@28: }
jb302@28: 
jb302@28: void
jb302@28: RETI(void) {
jb302@28:     /* implement me */
jb302@28: }
jb302@28: 
jb302@28: /* 0xDC - SJMP rel8 */
jb302@28: void
jb302@28: SJMP(void) {
jb302@34:     /* -1 because the fetch() increments the PC */
jb302@34:     set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@28: }
jb302@28: 
jb302@28: /* 0xDD - JMP @A+DPTR
jb302@28:  * 0xDE - JMP @DPTR */
jb302@28: void
jb302@28: JMP(void) {
jb302@34:     switch(IR) {
jb302@34:         
jb302@34:         case 0xDD:
jb302@34:             set_wide(PC, A + get_wide(DPTR));
jb302@34:             break;
jb302@34:         
jb302@34:         case 0xDE:
jb302@34:             set_wide(PC, get_wide(DPTR));
jb302@34:             break;
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE0 - JZ rel8 */
jb302@28: void
jb302@34: JZ(void) {
jb302@34:     if (get_flag(Z) == 1) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     /* skip rel8 if jump not needed */
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE1 - JNZ rel8 */
jb302@28: void
jb302@28: JNZ(void) {
jb302@34:     if (get_flag(Z) == 0) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE2 - JC rel8 */
jb302@28: void
jb302@34: JC(void) {
jb302@34:     if (get_flag(C) == 1) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE3 - JNC rel8 */
jb302@28: void
jb302@34: JNC(void) {
jb302@34:     if (get_flag(C) == 0) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE4 - JPO rel8 */
jb302@28: void
jb302@34: JPO(void) {
jb302@34:     /* P = 1 when parity even */
jb302@34:     if (get_flag(P) == 0) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@34: 
jb302@28: }
jb302@28: 
jb302@34: /* 0xE5 - JPE rel8 */
jb302@28: void
jb302@28: JPE(void) {
jb302@34:     if (get_flag(P) == 1) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE6 - JS rel8 */
jb302@28: void
jb302@34: JS(void) {
jb302@34:     if (get_flag(S) == 1) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@34: /* 0xE7 - JNS rel8 */
jb302@28: void
jb302@28: JNS(void) {
jb302@34:     if (get_flag(S) == 0) {
jb302@34:         set_wide(PC, get_wide(PC) + (signed char)fetch() -1);
jb302@34:     }
jb302@34:     else {
jb302@34:         inc_pc(1);
jb302@34:     }
jb302@28: }
jb302@28: 
jb302@35: /* 0xE8 - PUSH R0
jb302@35:  * 0xE9 - PUSH R1
jb302@35:  * 0xEA - PUSH R2
jb302@35:  * 0xEB - PUSH R3
jb302@35:  * 0xEC - PUSH DPH
jb302@35:  * 0xED - PUSH DPL
jb302@35:  * 0xEE - PUSH A
jb302@35:  * 0xEF - PUSH FLAGS */
jb302@28: void
jb302@28: PUSH(void) {
jb302@35:     if (NNN < 6) {
jb302@35:         mem[get_wide(SP)] = get_reg(NNN);
jb302@35:         set_wide(SP, get_wide(SP) + 1);
jb302@35: 
jb302@35:     }
jb302@35:     else {
jb302@35:         switch(IR) {
jb302@35:             
jb302@35:             case 0xEE:
jb302@35:                 mem[get_wide(SP)] = A;
jb302@35:                 set_wide(SP, get_wide(SP) + 1);
jb302@35:                 break;
jb302@35: 
jb302@35:             case 0xEF:
jb302@35:                 mem[get_wide(SP)] = flags;
jb302@35:                 set_wide(SP, get_wide(SP) + 1);
jb302@35:                 break;
jb302@35: 
jb302@35:             default:
jb302@35:                 break;
jb302@35:         }
jb302@35:     }
jb302@28: }
jb302@28: 
jb302@35: /* 0xF0 - POP R0
jb302@35:  * 0xF1 - POP R1
jb302@35:  * 0xF2 - POP R2
jb302@35:  * 0xF3 - POP R3
jb302@35:  * 0xF4 - POP DPH
jb302@35:  * 0xF5 - POP DPL
jb302@35:  * 0xF6 - POP A
jb302@35:  * 0xF7 - POP FLAGS */
jb302@28: void
jb302@35: POP(void) {
jb302@35:     if (NNN < 6) {
jb302@35:         set_wide(SP, get_wide(SP) - 1);
jb302@35:         set_reg(NNN, mem[get_wide(SP)]);
jb302@35:     }
jb302@35:     else {
jb302@35:         switch(IR) {
jb302@35:             
jb302@35:             case 0xF6:
jb302@35:                 set_wide(SP, get_wide(SP) - 1);
jb302@35:                 A = mem[get_wide(SP)];
jb302@35:                 break;
jb302@35: 
jb302@35:             case 0xF7:
jb302@35:                 set_wide(SP, get_wide(SP) - 1);
jb302@35:                 flags = mem[get_wide(SP)];
jb302@35:                 break;
jb302@35: 
jb302@35:             default:
jb302@35:                 break;
jb302@35:         }
jb302@35:     }
jb302@28: }
jb302@28: 
jb302@35: 
jb302@35: /* 0xF8 - MUL R0, R1 */
jb302@28: void
jb302@35: MUL(void) {
jb302@42:     tmpw = regs[R0] * regs[R1];
jb302@42:     regs[R0] = GHIGH(tmpw);
jb302@42:     regs[R1] = GLOW(tmpw);
jb302@28: }
jb302@28: 
jb302@35: /* 0xF9 - DIV R0, R1 */
jb302@28: void
jb302@35: DIV(void) {
jb302@42:     tmpw = regs[R0] / regs[R1];
jb302@42:     regs[R0] = GHIGH(tmpw);
jb302@42:     regs[R1] = GLOW(tmpw);
jb302@28: }
jb302@28: 
jb302@35: /* 0xFA - DA A */
jb302@28: void
jb302@35: DA(void) {
jb302@42:  if (((A & 0xF) > 9) | get_flag(AC) == 1) {
jb302@42:      A = A + 6;
jb302@42:  }
jb302@42:  if (((A & 0xF0) > 9) | get_flag(C) == 1) {
jb302@42:      A = A + 0x60;
jb302@42:  }
jb302@28: }
jb302@28: 
jb302@35: /* 0xFC - IN port_addr */
jb302@28: void
jb302@35: IN(void) {
jb302@35:  /* implement me */   
jb302@28: }
jb302@28: 
jb302@35: /* 0xFD - OUT port_addr */
jb302@28: void
jb302@28: OUT(void) {
jb302@35:  /* implement me */
jb302@28: }
jb302@28: 
jb302@35: /* 0xFE INT vect8 */
jb302@28: void
jb302@35: INT(void) {
jb302@35:  /* implement me */    
jb302@28: }
jb302@28: 
jb302@28: /* 0xFF - HLT */
jb302@28: void
jb302@28: HLT(void) {
jb302@42:  exit(0);
jb302@28: }