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Corrects RTS, adds the remainder of the direct flag manipulations.

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Thomas Harte
2021-01-20 20:16:55 -05:00
parent b9672c0669
commit 9f12ce2fb8
2 changed files with 15 additions and 3 deletions
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InstructionSets/M50740/Executor.cpp
+7 -3
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@@ -105,7 +105,7 @@ template <Operation operation, AddressingMode addressing_mode> void Executor::pe
#define next8() memory_[(program_counter_ + 1) & 0x1fff]
#define next16() (memory_[(program_counter_ + 1) & 0x1fff] | (memory_[(program_counter_ + 2) & 0x1fff] << 8))
printf("%04x\t%d %d\n", program_counter_ & 0x1fff, int(operation), int(addressing_mode));
printf("%04x\t%02x\t%d %d\t[x:%02x s:%02x]\n", program_counter_ & 0x1fff, memory_[program_counter_ & 0x1fff], int(operation), int(addressing_mode), x_, s_);
// Underlying assumption below: the instruction stream will never
// overlap with IO ports.
@@ -261,6 +261,9 @@ template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_u
case Operation::SET: index_mode_ = true; break;
case Operation::CLD: decimal_mode_ = false; break;
case Operation::SED: decimal_mode_ = true; break;
case Operation::CLC: carry_flag_ = 0; break;
case Operation::SEC: carry_flag_ = 1; break;
case Operation::CLV: overflow_result_ = 0; break;
case Operation::DEX: --x_; set_nz(x_); break;
case Operation::INX: ++x_; set_nz(x_); break;
@@ -272,8 +275,9 @@ template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_u
case Operation::RTS: {
uint16_t target = pull();
target |= pull() << 8;
++target;
set_program_counter(target);
set_program_counter(target+1);
--program_counter_; // To undo the unavoidable increment
// after exiting from here.
} break;
/*