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Added bus request/acknowledge logic.

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Thomas Harte 2017-06-03 19:09:47 -04:00
parent 7bd45d308a
commit 7898f643ac
1 changed files with 492 additions and 491 deletions
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41
Processors/Z80/Z80.hpp
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@ -195,13 +195,13 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
enum Interrupt: uint8_t {
IRQ = 0x01,
NMI = 0x02,
BUSREQ = 0x04,
Reset = 0x08,
PowerOn = 0x10
Reset = 0x04,
PowerOn = 0x08
};
uint8_t request_status_;
uint8_t last_request_status_;
bool irq_line_;
bool bus_request_line_;
uint8_t operation_;
RegisterPair temp16_;
@ -667,16 +667,11 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
public:
Processor() : MicroOpScheduler(),
halt_mask_(0xff),
sp_(0xffff),
pc_(0x0000),
a_(0xff),
interrupt_mode_(0),
iff1_(false),
iff2_(false),
number_of_cycles_(0),
request_status_(Interrupt::PowerOn),
last_request_status_(Interrupt::PowerOn),
irq_line_(false),
bus_request_line_(false),
pc_increment_(1) {
set_flags(0xff);
@ -768,6 +763,14 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
}
while(1) {
while(bus_request_line_) {
static MachineCycle bus_acknowledge_cycle = {BusOperation::BusAcknowledge, 1};
number_of_cycles_ -= static_cast<T *>(this)->perform_machine_cycle(bus_acknowledge_cycle) + 1;
if(!number_of_cycles_) return;
}
while(!bus_request_line_) {
const MicroOp *operation = scheduled_program_counter_;
scheduled_program_counter_++;
@ -1494,14 +1497,13 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
#pragma mark - Interrupt handling
case MicroOp::Reset:
// TODO
// iff1_ = iff2_ = false;
// interrupt_mode_ = 0;
// pc_.full = 0;
// sp_.full = 0xffff;
// a_ = 0xff;
// set_flags(0xff);
// i_ = r_ = 0;
iff1_ = iff2_ = false;
interrupt_mode_ = 0;
pc_.full = 0;
sp_.full = 0xffff;
a_ = 0xff;
set_flags(0xff);
i_ = r_ = 0;
break;
#pragma mark - Internal bookkeeping
@ -1520,6 +1522,7 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
return;
}
#undef set_parity
}
}
}
@ -1718,9 +1721,7 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
Sets the logical value of the bus request line.
*/
void set_bus_request_line(bool value) {
// Bus requests are level triggered and cannot be masked.
if(value) request_status_ |= Interrupt::BUSREQ;
else request_status_ &= ~Interrupt::BUSREQ;
bus_request_line_ = value;
}
/*!