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Cleaned up and implemented fast-tape hack. I've decided it'd be better to test some other software, potentially to give multiple issues to think about, rather than sitting around with just the one.

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This commit is contained in:
Thomas Harte 2017-06-11 16:42:49 -04:00
parent d12e50eb02
commit 84d2feb2e6
2 changed files with 34 additions and 21 deletions
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54
Machines/ZX8081/ZX8081.cpp
View File

@ -9,10 +9,12 @@
#include "ZX8081.hpp"
#include "../MemoryFuzzer.hpp"
#include "../../Storage/Tape/Parsers/ZX8081.hpp"
using namespace ZX8081;
namespace {
// The clock rate is 3.25Mhz.
const unsigned int ZX8081ClockRate = 3250000;
}
@ -22,7 +24,6 @@ Machine::Machine() :
ram_(1024),
key_states_{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
tape_player_(ZX8081ClockRate) {
// run at 3.25 Mhz
set_clock_rate(ZX8081ClockRate);
Memory::Fuzz(ram_);
tape_player_.set_motor_control(true);
@ -32,18 +33,12 @@ int Machine::perform_machine_cycle(const CPU::Z80::MachineCycle &cycle) {
video_->run_for_cycles(cycle.length);
tape_player_.run_for_cycles(cycle.length);
static uint64_t time = 0;
time += (uint64_t)cycle.length;
static uint8_t last_input = 0xff;
uint16_t refresh = 0;
uint16_t address = cycle.address ? *cycle.address : 0;
switch(cycle.operation) {
case CPU::Z80::BusOperation::Output:
// if((address&7) == 7) {
set_vsync(false);
line_counter_ = 0;
// }
set_vsync(false);
line_counter_ = 0;
break;
case CPU::Z80::BusOperation::Input: {
@ -58,13 +53,6 @@ int Machine::perform_machine_cycle(const CPU::Z80::MachineCycle &cycle) {
}
value &= ~(tape_player_.get_input() ? 0x00 : 0x80);
// if((last_input ^ value) & 0x80) {
// printf("%lld\n", time);
// time = 0;
// last_input = value;
// }
// printf("[%02x]\n", value);
}
*cycle.value = value;
} break;
@ -76,13 +64,29 @@ int Machine::perform_machine_cycle(const CPU::Z80::MachineCycle &cycle) {
break;
case CPU::Z80::BusOperation::ReadOpcode:
// if(address >= 0x22f && address < 0x24d && count) {
// printf("%04x A:%02x BC:%04x DE:%04x\n", address, get_value_of_register(CPU::Z80::Register::A), get_value_of_register(CPU::Z80::Register::BC), get_value_of_register(CPU::Z80::Register::DE));
// count--;
// }
set_hsync(false);
// The ZX80 and 81 signal an interrupt while refresh is active and bit 6 of the refresh
// address is low. The Z80 signals a refresh, providing the refresh address during the
// final two cycles of an opcode fetch. Therefore communicate a transient signalling
// of the IRQ line if necessary.
refresh = get_value_of_register(CPU::Z80::Register::Refresh);
set_interrupt_line(!(refresh & 0x40), -2);
set_interrupt_line(false);
// Check for use of the fast tape hack.
if(address == tape_trap_address_) { // TODO: && fast_tape_hack_enabled_
Storage::Tape::ZX8081::Parser parser;
int next_byte = parser.get_next_byte(tape_player_.get_tape());
if(next_byte != -1) {
uint16_t hl = get_value_of_register(CPU::Z80::Register::HL);
ram_[hl & 1023] = (uint8_t)next_byte;
*cycle.value = 0x00;
set_value_of_register(CPU::Z80::Register::ProgramCounter, tape_return_address_);
return 0;
}
}
case CPU::Z80::BusOperation::Read:
if((address & 0xc000) == 0x0000) *cycle.value = rom_[address & (rom_.size() - 1)];
else if((address & 0x4000) == 0x4000) {
@ -137,7 +141,15 @@ void Machine::run_for_cycles(int number_of_cycles) {
void Machine::configure_as_target(const StaticAnalyser::Target &target) {
// TODO: pay attention to the target; it can't currently specify a ZX81
// so assume a ZX80 if we got here.
rom_ = zx80_rom_;
if(true) {
rom_ = zx80_rom_;
tape_trap_address_ = 0x220;
tape_return_address_ = 0x248;
} else {
rom_ = zx81_rom_;
tape_trap_address_ = 0x37c;
tape_return_address_ = 0x380;
}
if(target.tapes.size()) {
tape_player_.set_tape(target.tapes.front());

1
Machines/ZX8081/ZX8081.hpp
View File

@ -65,6 +65,7 @@ class Machine:
std::shared_ptr<Video> video_;
std::vector<uint8_t> zx81_rom_, zx80_rom_, rom_;
std::vector<uint8_t> ram_;
uint16_t tape_trap_address_, tape_return_address_;
bool vsync_, hsync_;
int line_counter_;