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mirror of https://github.com/TomHarte/CLK.git synced 2024-06-25 18:30:07 +00:00

Factors Apple's RTC out of the Macintosh.

This commit is contained in:
Thomas Harte 2020-10-29 21:03:02 -04:00
parent 5a8b8478d2
commit 1249fb598b
4 changed files with 206 additions and 180 deletions

View File

@ -0,0 +1,192 @@
//
// RealTimeClock.hpp
// Clock Signal
//
// Created by Thomas Harte on 07/05/2019.
// Copyright © 2019 Thomas Harte. All rights reserved.
//
#ifndef Apple_RealTimeClock_hpp
#define Apple_RealTimeClock_hpp
namespace Apple {
namespace Clock {
/*!
Models Apple's real-time clocks, as contained in the Macintosh and IIgs.
Since tracking of time is pushed to this class, it is assumed
that whomever is translating real time into emulated time
will also signal interrupts this is just the storage and time counting.
*/
class ClockStorage {
public:
ClockStorage() {
// TODO: this should persist, if possible, rather than
// being default initialised.
constexpr uint8_t default_data[] = {
0xa8, 0x00, 0x00, 0x00,
0xcc, 0x0a, 0xcc, 0x0a,
0x00, 0x00, 0x00, 0x00,
0x00, 0x02, 0x63, 0x00,
0x03, 0x88, 0x00, 0x4c
};
memcpy(data_, default_data, sizeof(data_));
memset(&data_[sizeof(default_data)], 0xff, sizeof(data_) - sizeof(default_data));
}
/*!
Advances the clock by 1 second.
The caller should also signal an interrupt.
*/
void update() {
for(int c = 0; c < 4; ++c) {
++seconds_[c];
if(seconds_[c]) break;
}
}
protected:
static constexpr uint16_t NoResult = 0x100;
static constexpr uint16_t DidWrite = 0x101;
uint16_t perform(uint8_t command) {
/*
Documented commands:
z0000001 Seconds register 0 (lowest order byte)
z0000101 Seconds register 1
z0001001 Seconds register 2
z0001101 Seconds register 3
00110001 Test register (write only)
00110101 Write-protect register (write only)
z010aa01 RAM addresses 0x10 - 0x13
z1aaaa01 RAM addresses 0x00 0x0f
z0111abc, followed by 0defgh00
RAM address abcdefgh
z = 1 => a read; z = 0 => a write.
The top bit of the write-protect register enables (0) or disables (1)
writes to other locations.
All the documentation says about the test register is to set the top
two bits to 0 for normal operation. Abnormal operation is undefined.
*/
if(!is_writing_) {
// Decode an address; use values >= 0x100 to represent clock time.
address_ = (command >> 2) & 0x1f;
if(address_ < 4) {
address_ |= 0x100;
} else if(address_ >= 0x10) {
address_ &= 0xf;
} else if(address_ >= 0x8 && address_ <= 0xb) {
address_ = 0x10 + (address_ & 0x3);
}
// If this is a read, return a result; otherwise prepare to write.
if(command & 0x80) {
return (address_ & 0x100) ? seconds_[address_ & 0xff] : data_[address_];
}
is_writing_ = true;
return NoResult;
} else {
// First test: is this to the write-protect register?
if(address_ == 0xd) {
write_protect_ = command;
}
// No other writing is permitted if the write protect
// register won't allow it.
if(!(write_protect_ & 0x80)) {
if(address_ & 0x100) {
seconds_[address_ & 0xff] = command;
} else {
data_[address_] = command;
}
}
is_writing_ = false;
return DidWrite;
}
}
private:
uint8_t data_[256];
uint8_t seconds_[4];
uint8_t write_protect_;
bool is_writing_ = false;
int address_;
};
/*!
Provides the serial interface implemented by the Macintosh.
*/
class SerialClock: public ClockStorage {
public:
/*!
Sets the current clock and data inputs to the clock.
*/
void set_input(bool clock, bool data) {
// The data line is valid when the clock transitions to level 0.
if(clock && !previous_clock_) {
// Shift into the command_ register, no matter what.
command_ = uint16_t((command_ << 1) | (data ? 1 : 0));
result_ <<= 1;
// Increment phase.
++phase_;
// If a whole byte has been collected, push it onwards.
if(!(phase_&7)) {
// Begin pessimistically.
const auto effect = perform(uint8_t(command_));
switch(effect) {
case ClockStorage::NoResult:
break;
default:
result_ = uint8_t(effect);
break;
case ClockStorage::DidWrite:
abort();
break;
}
}
}
previous_clock_ = clock;
}
/*!
Reads the current data output level from the clock.
*/
bool get_data() {
return !!(result_ & 0x80);
}
/*!
Announces that a serial command has been aborted.
*/
void abort() {
result_ = 0;
phase_ = 0;
command_ = 0;
}
private:
int phase_ = 0;
uint16_t command_;
uint8_t result_ = 0;
bool previous_clock_ = false;
};
}
}
#endif /* Apple_RealTimeClock_hpp */

View File

@ -13,7 +13,6 @@
#include "DeferredAudio.hpp"
#include "DriveSpeedAccumulator.hpp"
#include "Keyboard.hpp"
#include "RealTimeClock.hpp"
#include "Video.hpp"
#include "../../MachineTypes.hpp"
@ -32,6 +31,7 @@
#include "../../../Components/5380/ncr5380.hpp"
#include "../../../Components/6522/6522.hpp"
#include "../../../Components/8530/z8530.hpp"
#include "../../../Components/AppleClock/AppleClock.hpp"
#include "../../../Components/DiskII/IWM.hpp"
#include "../../../Components/DiskII/MacintoshDoubleDensityDrive.hpp"
#include "../../../Processors/68000/68000.hpp"
@ -648,7 +648,7 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
class VIAPortHandler: public MOS::MOS6522::PortHandler {
public:
VIAPortHandler(ConcreteMachine &machine, RealTimeClock &clock, Keyboard &keyboard, DeferredAudio &audio, IWMActor &iwm, Inputs::QuadratureMouse &mouse) :
VIAPortHandler(ConcreteMachine &machine, Apple::Clock::SerialClock &clock, Keyboard &keyboard, DeferredAudio &audio, IWMActor &iwm, Inputs::QuadratureMouse &mouse) :
machine_(machine), clock_(clock), keyboard_(keyboard), audio_(audio), iwm_(iwm), mouse_(mouse) {}
using Port = MOS::MOS6522::Port;
@ -751,7 +751,7 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
private:
ConcreteMachine &machine_;
RealTimeClock &clock_;
Apple::Clock::SerialClock &clock_;
Keyboard &keyboard_;
DeferredAudio &audio_;
IWMActor &iwm_;
@ -766,7 +766,7 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
DeferredAudio audio_;
Video video_;
RealTimeClock clock_;
Apple::Clock::SerialClock clock_;
Keyboard keyboard_;
MOS::MOS6522::MOS6522<VIAPortHandler> via_;

View File

@ -1,173 +0,0 @@
//
// RealTimeClock.hpp
// Clock Signal
//
// Created by Thomas Harte on 07/05/2019.
// Copyright © 2019 Thomas Harte. All rights reserved.
//
#ifndef RealTimeClock_hpp
#define RealTimeClock_hpp
#include "../../Utility/MemoryFuzzer.hpp"
namespace Apple {
namespace Macintosh {
/*!
Models the storage component of Apple's real-time clock.
Since tracking of time is pushed to this class, it is assumed
that whomever is translating real time into emulated time
will notify the VIA of a potential interrupt.
*/
class RealTimeClock {
public:
RealTimeClock() {
// TODO: this should persist, if possible, rather than
// being default initialised.
const uint8_t default_data[] = {
0xa8, 0x00, 0x00, 0x00,
0xcc, 0x0a, 0xcc, 0x0a,
0x00, 0x00, 0x00, 0x00,
0x00, 0x02, 0x63, 0x00,
0x03, 0x88, 0x00, 0x4c
};
memcpy(data_, default_data, sizeof(data_));
}
/*!
Advances the clock by 1 second.
The caller should also notify the VIA.
*/
void update() {
for(int c = 0; c < 4; ++c) {
++seconds_[c];
if(seconds_[c]) break;
}
}
/*!
Sets the current clock and data inputs to the clock.
*/
void set_input(bool clock, bool data) {
/*
Documented commands:
z0000001 Seconds register 0 (lowest order byte)
z0000101 Seconds register 1
z0001001 Seconds register 2
z0001101 Seconds register 3
00110001 Test register (write only)
00110101 Write-protect register (write only)
z010aa01 RAM addresses 0x10 - 0x13
z1aaaa01 RAM addresses 0x00 0x0f
z = 1 => a read; z = 0 => a write.
The top bit of the write-protect register enables (0) or disables (1)
writes to other locations.
All the documentation says about the test register is to set the top
two bits to 0 for normal operation. Abnormal operation is undefined.
The data line is valid when the clock transitions to level 0.
*/
if(clock && !previous_clock_) {
// Shift into the command_ register, no matter what.
command_ = uint16_t((command_ << 1) | (data ? 1 : 0));
result_ <<= 1;
// Increment phase.
++phase_;
// When phase hits 8, inspect the command.
// If it's a read, prepare a result.
if(phase_ == 8) {
if(command_ & 0x80) {
// A read.
const auto address = (command_ >> 2) & 0x1f;
// Begin pessimistically.
result_ = 0xff;
if(address < 4) {
result_ = seconds_[address];
} else if(address >= 0x10) {
result_ = data_[address & 0xf];
} else if(address >= 0x8 && address <= 0xb) {
result_ = data_[0x10 + (address & 0x3)];
}
}
}
// If phase hits 16 and this was a read command,
// just stop. If it was a write command, do the
// actual write.
if(phase_ == 16) {
if(!(command_ & 0x8000)) {
// A write.
const auto address = (command_ >> 10) & 0x1f;
const uint8_t value = uint8_t(command_ & 0xff);
// First test: is this to the write-protect register?
if(address == 0xd) {
write_protect_ = value;
}
// No other writing is permitted if the write protect
// register won't allow it.
if(!(write_protect_ & 0x80)) {
if(address < 4) {
seconds_[address] = value;
} else if(address >= 0x10) {
data_[address & 0xf] = value;
} else if(address >= 0x8 && address <= 0xb) {
data_[0x10 + (address & 0x3)] = value;
}
}
}
// A phase of 16 always ends the command, so reset here.
abort();
}
}
previous_clock_ = clock;
}
/*!
Reads the current data output level from the clock.
*/
bool get_data() {
return !!(result_ & 0x80);
}
/*!
Announces that a serial command has been aborted.
*/
void abort() {
result_ = 0;
phase_ = 0;
command_ = 0;
}
private:
uint8_t data_[0x14];
uint8_t seconds_[4];
uint8_t write_protect_;
int phase_ = 0;
uint16_t command_;
uint8_t result_ = 0;
bool previous_clock_ = false;
};
}
}
#endif /* RealTimeClock_hpp */

View File

@ -1314,6 +1314,7 @@
4B8D287E1F77207100645199 /* TrackSerialiser.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = TrackSerialiser.hpp; sourceTree = "<group>"; };
4B8DF4D62546561300F3433C /* MemoryMap.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MemoryMap.hpp; sourceTree = "<group>"; };
4B8DF4D725465B7500F3433C /* IIgsMemoryMapTests.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = IIgsMemoryMapTests.mm; sourceTree = "<group>"; };
4B8DF4ED254B840B00F3433C /* AppleClock.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = AppleClock.hpp; sourceTree = "<group>"; };
4B8E4ECD1DCE483D003716C3 /* KeyboardMachine.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = KeyboardMachine.hpp; sourceTree = "<group>"; };
4B8EF6071FE5AF830076CCDD /* LowpassSpeaker.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = LowpassSpeaker.hpp; sourceTree = "<group>"; };
4B8FE2141DA19D5F0090D3CE /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = Base; path = "Clock Signal/Base.lproj/Atari2600Options.xib"; sourceTree = SOURCE_ROOT; };
@ -1736,7 +1737,6 @@
4BCF1FA21DADC3DD0039D2E7 /* Oric.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Oric.cpp; path = Oric/Oric.cpp; sourceTree = "<group>"; };
4BCF1FA31DADC3DD0039D2E7 /* Oric.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; name = Oric.hpp; path = Oric/Oric.hpp; sourceTree = "<group>"; };
4BD060A51FE49D3C006E14BE /* Speaker.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = Speaker.hpp; sourceTree = "<group>"; };
4BD0692B22828A2D00D2A54F /* RealTimeClock.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = RealTimeClock.hpp; sourceTree = "<group>"; };
4BD0FBC2233706A200148981 /* CSApplication.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = CSApplication.m; sourceTree = "<group>"; };
4BD191D9219113B80042E144 /* OpenGL.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = OpenGL.hpp; sourceTree = "<group>"; };
4BD191F22191180E0042E144 /* ScanTarget.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = ScanTarget.cpp; sourceTree = "<group>"; };
@ -3014,6 +3014,14 @@
path = AmstradCPC;
sourceTree = "<group>";
};
4B8DF4EC254B840B00F3433C /* AppleClock */ = {
isa = PBXGroup;
children = (
4B8DF4ED254B840B00F3433C /* AppleClock.hpp */,
);
path = AppleClock;
sourceTree = "<group>";
};
4B8EF6051FE5AF830076CCDD /* Implementation */ = {
isa = PBXGroup;
children = (
@ -3456,7 +3464,6 @@
children = (
4B85322922778E4200F26553 /* Comparative68000.hpp */,
4B90467222C6FA31000E2074 /* TestRunner68000.hpp */,
4B90467522C6FD6E000E2074 /* 68000ArithmeticTests.mm */,
4B9D0C4A22C7D70900DE1AD3 /* 68000BCDTests.mm */,
4B90467322C6FADD000E2074 /* 68000BitwiseTests.mm */,
4B680CE123A5553100451D43 /* 68000ComparativeTests.mm */,
@ -3692,6 +3699,7 @@
4BB244D222AABAF500BE20E5 /* 8530 */,
4B0E04F71FC9F2C800F43484 /* 9918 */,
4B92E267234AE35000CD6D1B /* 68901 */,
4B8DF4EC254B840B00F3433C /* AppleClock */,
4B595FAA2086DFBA0083CAA8 /* AudioToggle */,
4B4A762D1DB1A35C007AAE2E /* AY38910 */,
4B302181208A550100773308 /* DiskII */,
@ -3770,7 +3778,6 @@
4BB4BFAB22A33D710069048D /* DriveSpeedAccumulator.hpp */,
4BDB3D8522833321002D3CEE /* Keyboard.hpp */,
4BCE0059227CFFCA000CA200 /* Macintosh.hpp */,
4BD0692B22828A2D00D2A54F /* RealTimeClock.hpp */,
4BCE005F227D39AB000CA200 /* Video.hpp */,
);
path = Macintosh;