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This proves that bytes are being deposited properly. For the first 36 anyway, and with no announcement.

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This commit is contained in:
Thomas Harte 2016-08-16 21:09:50 -04:00
parent 12f8aff65b
commit dfe9fb83ef
2 changed files with 20 additions and 10 deletions
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5
Machines/Commodore/Vic-20/Vic20.cpp
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@ -108,6 +108,11 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
// printf("%04x\n", address); // printf("%04x\n", address);
// } // }
if(operation == CPU6502::BusOperation::Write && (address >= 0x033C && address < 0x033C + 192))
{
printf("\n[%04x] <- %02x\n", address, *value);
}
// run the phase-1 part of this cycle, in which the VIC accesses memory // run the phase-1 part of this cycle, in which the VIC accesses memory
_mos6560->run_for_cycles(1); _mos6560->run_for_cycles(1);

25
Storage/Tape/Formats/TapePRG.cpp
View File

@ -40,6 +40,7 @@ TapePRG::~TapePRG()
Tape::Pulse TapePRG::get_next_pulse() Tape::Pulse TapePRG::get_next_pulse()
{ {
// these are all microseconds per pole
static const unsigned int leader_zero_length = 179; static const unsigned int leader_zero_length = 179;
static const unsigned int zero_length = 169; static const unsigned int zero_length = 169;
static const unsigned int one_length = 247; static const unsigned int one_length = 247;
@ -57,7 +58,7 @@ Tape::Pulse TapePRG::get_next_pulse()
case WordMarker: pulse.length.length = (_bitPhase&2) ? one_length : marker_length; break; case WordMarker: pulse.length.length = (_bitPhase&2) ? one_length : marker_length; break;
case EndOfBlock: pulse.length.length = (_bitPhase&2) ? zero_length : marker_length; break; case EndOfBlock: pulse.length.length = (_bitPhase&2) ? zero_length : marker_length; break;
} }
pulse.length.clock_rate = 2000000; pulse.length.clock_rate = 1000000;
pulse.type = (_bitPhase&1) ? Pulse::High : Pulse::Low; pulse.type = (_bitPhase&1) ? Pulse::High : Pulse::Low;
return pulse; return pulse;
} }
@ -72,6 +73,9 @@ void TapePRG::reset()
void TapePRG::get_next_output_token() void TapePRG::get_next_output_token()
{ {
static const int block_length = 192; // not counting the checksum
static const int countdown_bytes = 9;
// the lead-in is 20,000 instances of the lead-in pair; every other phase begins with 5000 // the lead-in is 20,000 instances of the lead-in pair; every other phase begins with 5000
// before doing whatever it should be doing // before doing whatever it should be doing
if(_filePhase == FilePhaseLeadIn || _phaseOffset < 5000) if(_filePhase == FilePhaseLeadIn || _phaseOffset < 5000)
@ -90,33 +94,34 @@ void TapePRG::get_next_output_token()
int block_offset = _phaseOffset - 5000; int block_offset = _phaseOffset - 5000;
int bit_offset = block_offset % 10; int bit_offset = block_offset % 10;
int byte_offset = block_offset / 10; int byte_offset = block_offset / 10;
_phaseOffset++;
if(byte_offset == 200) if(byte_offset == block_length + countdown_bytes + 1) // i.e. after the checksum
{ {
_phaseOffset = 0; _phaseOffset = 0;
_filePhase = FilePhaseData; // TODO _filePhase = FilePhaseData; // TODO
_outputToken = EndOfBlock; _outputToken = EndOfBlock;
printf("\n===\n");
return; return;
} }
_phaseOffset++;
if(bit_offset == 0) if(bit_offset == 0)
{ {
// the first nine bytes are countdown; the high bit is set if this is a header // the first nine bytes are countdown; the high bit is set if this is a header
if(byte_offset < 9) if(byte_offset < countdown_bytes)
{ {
_output_byte = (uint8_t)(9 - byte_offset) | 0x80; _output_byte = (uint8_t)(countdown_bytes - byte_offset) | 0x80;
} }
else if(byte_offset == 199) else if(byte_offset == countdown_bytes + block_length)
{ {
_output_byte = _check_digit; _output_byte = _check_digit;
} }
else else
{ {
if(byte_offset == 9) _check_digit = 0; if(byte_offset == countdown_bytes) _check_digit = 0;
if(_filePhase == FilePhaseHeader) if(_filePhase == FilePhaseHeader)
{ {
switch(byte_offset - 9) switch(byte_offset - countdown_bytes)
{ {
case 0: _output_byte = 0x03; break; case 0: _output_byte = 0x03; break;
case 1: _output_byte = _load_address & 0xff; break; case 1: _output_byte = _load_address & 0xff; break;
@ -149,10 +154,10 @@ void TapePRG::get_next_output_token()
case 0: case 0:
_outputToken = WordMarker; _outputToken = WordMarker;
break; break;
default: default: // i.e. 1–8
_outputToken = (_output_byte & (1 << (bit_offset - 1))) ? One : Zero; _outputToken = (_output_byte & (1 << (bit_offset - 1))) ? One : Zero;
break; break;
case 1: case 9:
{ {
uint8_t parity = _outputToken; uint8_t parity = _outputToken;
parity ^= (parity >> 4); parity ^= (parity >> 4);