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Refactoring on the MC6850 and associated test board code.

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Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
This commit is contained in:
Adrian Conlon 2018-09-29 14:31:50 +01:00
parent 8d3551e681
commit 8ea7bf5d68
4 changed files with 88 additions and 44 deletions
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56
MC6809/test/Board.cpp
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@ -12,19 +12,29 @@ Board::Board(const Configuration& configuration)
void Board::initialise() {
// Load our BASIC interpreter
const auto directory = m_configuration.getRomDirectory() + "\\";
loadHexFile(directory + "ExBasROM.hex");
if (m_configuration.isDebugMode()) {
CPU().ExecutingInstruction.connect(std::bind(&Board::Cpu_ExecutingInstruction_Debug, this, std::placeholders::_1));
CPU().ExecutedInstruction.connect(std::bind(&Board::Cpu_ExecutedInstruction_Debug, this, std::placeholders::_1));
}
// Get the CPU ready for action
CPU().powerOn();
CPU().raise(CPU().NMI());
CPU().raise(CPU().FIRQ());
CPU().reset();
WritingByte.connect(std::bind(&Board::Bus_WritingByte_Acia, this, std::placeholders::_1));
ReadingByte.connect(std::bind(&Board::Bus_ReadingByte_Acia, this, std::placeholders::_1));
CPU().ExecutedInstruction.connect(std::bind(&Board::Cpu_ExecutedInstruction_Acia, this, std::placeholders::_1));
// Get the ACIA ready for action
ACIA().powerOn();
ACIA().lower(ACIA().RW()); // Write
ACIA().lower(ACIA().RS()); // Registers
ACIA().raise(ACIA().CS0()); // Chip select
ACIA().raise(ACIA().CS1()); // "
ACIA().lower(ACIA().CS2()); // "
ACIA().DATA() = EightBit::mc6850::CR0 | EightBit::mc6850::CR1; // Master reset
// Get the reset out of the way...
ACIA().step(1);
// Once the reset has completed, we can wire the ACIA event handlers...
ACIA().Accessing.connect(std::bind(&Board::Acia_Accessing, this, std::placeholders::_1));
ACIA().Accessed.connect(std::bind(&Board::Acia_Accessed, this, std::placeholders::_1));
@ -34,16 +44,16 @@ void Board::initialise() {
ACIA().Receiving.connect(std::bind(&Board::Acia_Receiving, this, std::placeholders::_1));
ACIA().Received.connect(std::bind(&Board::Acia_Received, this, std::placeholders::_1));
CPU().powerOn();
CPU().raise(CPU().NMI());
CPU().raise(CPU().FIRQ());
CPU().reset();
// Wire bus events...
WrittenByte.connect(std::bind(&Board::Bus_WrittenByte_Acia, this, std::placeholders::_1));
ReadingByte.connect(std::bind(&Board::Bus_ReadingByte_Acia, this, std::placeholders::_1));
ACIA().powerOn();
ACIA().RW() = EightBit::Chip::PinLevel::Low; // Write
ACIA().RS() = EightBit::Chip::PinLevel::Low; // Registers
EightBit::Processor::setFlag(ACIA().DATA(), EightBit::mc6850::CR0 | EightBit::mc6850::CR1);
ACIA().step(1); // Get the reset out of the way...
// Wire CPU events
CPU().ExecutedInstruction.connect(std::bind(&Board::Cpu_ExecutedInstruction_Acia, this, std::placeholders::_1));
if (m_configuration.isDebugMode()) {
CPU().ExecutingInstruction.connect(std::bind(&Board::Cpu_ExecutingInstruction_Debug, this, std::placeholders::_1));
CPU().ExecutedInstruction.connect(std::bind(&Board::Cpu_ExecutedInstruction_Debug, this, std::placeholders::_1));
}
}
void Board::Cpu_ExecutingInstruction_Debug(EightBit::mc6809&) {
@ -76,10 +86,10 @@ EightBit::MemoryMapping Board::mapping(uint16_t address) {
return { m_rom, 0xc000, EightBit::MemoryMapping::ReadOnly };
}
void Board::Bus_WritingByte_Acia(EightBit::EventArgs&) {
void Board::Bus_WrittenByte_Acia(EightBit::EventArgs&) {
updateAciaPins(EightBit::Chip::Low);
if (ACIA().selected())
ACIA().DATA() = DATA();
ACIA().DATA() = peek(ADDRESS());
}
void Board::Bus_ReadingByte_Acia(EightBit::EventArgs&) {
@ -91,10 +101,10 @@ void Board::Bus_ReadingByte_Acia(EightBit::EventArgs&) {
void Board::updateAciaPins(const EightBit::Chip::PinLevel rw) {
ACIA().RW() = rw;
ACIA().DATA() = DATA();
ACIA().RS() = ADDRESS().word & EightBit::Chip::Bit0 ? EightBit::Chip::PinLevel::High : EightBit::Chip::PinLevel::Low;
ACIA().CS0() = ADDRESS().word & EightBit::Chip::Bit15 ? EightBit::Chip::PinLevel::High : EightBit::Chip::PinLevel::Low;
ACIA().CS1() = ADDRESS().word & EightBit::Chip::Bit13 ? EightBit::Chip::PinLevel::High : EightBit::Chip::PinLevel::Low;
ACIA().CS2() = ADDRESS().word & EightBit::Chip::Bit14 ? EightBit::Chip::PinLevel::High : EightBit::Chip::PinLevel::Low;
ADDRESS().word & EightBit::Chip::Bit0 ? ACIA().raise(ACIA().RS()) : ACIA().lower(ACIA().RS());
ADDRESS().word & EightBit::Chip::Bit15 ? ACIA().raise(ACIA().CS0()) : ACIA().lower(ACIA().CS0());
ADDRESS().word & EightBit::Chip::Bit13 ? ACIA().raise(ACIA().CS1()) : ACIA().lower(ACIA().CS1());
ADDRESS().word & EightBit::Chip::Bit14 ? ACIA().raise(ACIA().CS2()) : ACIA().lower(ACIA().CS2());
}
void Board::Cpu_ExecutedInstruction_Acia(EightBit::mc6809&) {

2
MC6809/test/Board.h
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@ -53,7 +53,7 @@ private:
// ACIA handling
void Bus_WritingByte_Acia(EightBit::EventArgs&);
void Bus_WrittenByte_Acia(EightBit::EventArgs&);
void Bus_ReadingByte_Acia(EightBit::EventArgs&);
void Cpu_ExecutedInstruction_Acia(EightBit::mc6809&);

74
MC6850/inc/MC6850.h
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@ -49,24 +49,58 @@ namespace EightBit {
// *** Data bit is "don't case" in 7-bit plus parity modes
enum ControlRegisters {
CR0 = 0b1,
CR1 = 0b10,
CR2 = 0b100,
CR3 = 0b1000,
CR4 = 0b10000,
CR5 = 0b100000,
CR6 = 0b1000000,
CR7 = 0b10000000
CR0 = 0b1, // Counter divide
CR1 = 0b10, // "
CR2 = 0b100, // Word select
CR3 = 0b1000, // "
CR4 = 0b10000, // "
CR5 = 0b100000, // Transmit control
CR6 = 0b1000000, // "
CR7 = 0b10000000 // Receive control
};
// CR0 and CR1
enum CounterDivideSelect {
One = 0b00,
Sixteen = 0b01,
SixtyFour = 0b10,
MasterReset = 0b11
};
// CR2, CR3 and CR4
enum WordSelect {
SevenEvenTwo = 0b000,
SevenOddTwo = 0b001,
SevenEvenOne = 0b010,
SevenOddOne = 0b011,
EightTwo = 0b100,
EightOne = 0b101,
EightEvenOne = 0b110,
EightOddOne = 0b111,
};
// CR5 and CR6
enum TransmitterControl {
ReadyLowInterruptDisabled = 0b00,
ReadyLowInterruptEnabled = 0b01,
ReadyHighInterruptDisabled = 0b10,
ReadyLowInterruptDisabledTransmitBreak = 0b11,
};
// CR7
enum ReceiveControl {
ReceiveInterruptDisable = 0b0,
ReceiveInterruptEnable = 0b1, // Triggers on: RDR full, overrun, DCD low -> high
};
enum StatusRegisters {
STATUS_RDRF = 0b1,
STATUS_TDRE = 0b10,
STATUS_DCD = 0b100,
STATUS_CTS = 0b1000,
STATUS_FE = 0b10000,
STATUS_OVRN = 0b100000,
STATUS_PE = 0b1000000,
STATUS_RDRF = 0b1,
STATUS_TDRE = 0b10,
STATUS_DCD = 0b100,
STATUS_CTS = 0b1000,
STATUS_FE = 0b10000,
STATUS_OVRN = 0b100000,
STATUS_PE = 0b1000000,
STATUS_IRQ = 0b10000000,
};
@ -149,10 +183,10 @@ namespace EightBit {
uint8_t m_data;
// Control registers
int m_counterDivide;
int m_wordConfiguration;
int m_transmitControl;
int m_receiveControl;
CounterDivideSelect m_counterDivide;
WordSelect m_wordSelect;
TransmitterControl m_transmitControl;
ReceiveControl m_receiveControl;
// Status registers
uint8_t m_status;

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MC6850/src/MC6850.cpp
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