3 |
|
* EmulateCycle() function, the same for |
4 |
|
* both 6510 and 6502) |
5 |
|
* |
6 |
< |
* Frodo (C) 1994-1997,2002-2003 Christian Bauer |
6 |
> |
* Frodo (C) 1994-1997,2002-2005 Christian Bauer |
7 |
|
* |
8 |
|
* This program is free software; you can redistribute it and/or modify |
9 |
|
* it under the terms of the GNU General Public License as published by |
91 |
|
case 0: |
92 |
|
read_to(pc++, op); |
93 |
|
state = ModeTab[op]; |
94 |
+ |
opflags = 0; |
95 |
|
break; |
96 |
|
|
97 |
|
|
739 |
|
read_idle(sp++ | 0x100); |
740 |
|
state = O_PLP2; |
741 |
|
break; |
742 |
< |
case O_PLP2: |
742 |
> |
case O_PLP2: { |
743 |
> |
bool old_i_flag = i_flag; |
744 |
|
pop_flags(); |
745 |
+ |
if (!old_i_flag && i_flag) { |
746 |
+ |
opflags |= OPFLAG_IRQ_DISABLED; |
747 |
+ |
} else if (old_i_flag && !i_flag) { |
748 |
+ |
opflags |= OPFLAG_IRQ_ENABLED; |
749 |
+ |
} |
750 |
|
Last; |
751 |
+ |
} |
752 |
|
|
753 |
|
|
754 |
|
// Jump/branch group |
850 |
|
push_flags(true); |
851 |
|
i_flag = true; |
852 |
|
#ifndef IS_CPU_1541 |
853 |
< |
if (interrupt.intr[INT_NMI]) { // BRK interrupted by NMI? |
853 |
> |
if (interrupt.intr[INT_NMI]) { // BRK interrupted by NMI? |
854 |
|
interrupt.intr[INT_NMI] = false; // Simulate an edge-triggered input |
855 |
|
state = 0x0015; // Jump to NMI sequence |
856 |
|
break; |
859 |
|
state = O_BRK4; |
860 |
|
break; |
861 |
|
case O_BRK4: |
854 |
– |
#ifndef IS_CPU_1541 |
855 |
– |
first_nmi_cycle++; // Delay NMI |
856 |
– |
#endif |
862 |
|
read_to(0xfffe, pc); |
863 |
|
state = O_BRK5; |
864 |
|
break; |
900 |
|
Branch(!(n_flag & 0x80)); |
901 |
|
|
902 |
|
case O_BRANCH_NP: // No page crossed |
903 |
< |
first_irq_cycle++; // Delay IRQ |
899 |
< |
#ifndef IS_CPU_1541 |
900 |
< |
first_nmi_cycle++; // Delay NMI |
901 |
< |
#endif |
903 |
> |
opflags |= OPFLAG_INT_DELAYED; |
904 |
|
read_idle(pc); |
905 |
|
pc = ar; |
906 |
|
Last; |
945 |
|
|
946 |
|
case O_SEI: |
947 |
|
read_idle(pc); |
948 |
+ |
if (!i_flag) |
949 |
+ |
opflags |= OPFLAG_IRQ_DISABLED; |
950 |
|
i_flag = true; |
951 |
|
Last; |
952 |
|
|
953 |
|
case O_CLI: |
954 |
|
read_idle(pc); |
955 |
+ |
if (i_flag) |
956 |
+ |
opflags |= OPFLAG_IRQ_ENABLED; |
957 |
|
i_flag = false; |
958 |
|
Last; |
959 |
|
|
1077 |
|
v_flag = (data ^ a) & 0x40; |
1078 |
|
if ((data & 0x0f) + (data & 0x01) > 5) |
1079 |
|
a = a & 0xf0 | (a + 6) & 0x0f; |
1080 |
< |
if (c_flag = ((data + (data & 0x10)) & 0x1f0) > 0x50) |
1080 |
> |
if ((c_flag = ((data + (data & 0x10)) & 0x1f0) > 0x50) != 0) |
1081 |
|
a += 0x60; |
1082 |
|
} |
1083 |
|
Last; |