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Implemented disk writes (roughly). Bravo now works. DIEX passes with writes enabled. Begun investigation into drive selection logic. Added Mesa source code with annotation, is displayed in ROM1 tab.

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This commit is contained in:
Josh Dersch
2015-12-02 12:39:10 -08:00
parent f256042cf4
commit 2c2ea68a63
12 changed files with 1389 additions and 1242 deletions
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191
Contralto/IO/DiskController.cs
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@@ -16,7 +16,7 @@ namespace Contralto.IO
_pack = new DiabloPack(DiabloDiskType.Diablo31);
// TODO: this does not belong here.
FileStream fs = new FileStream("Disk\\games.dsk", FileMode.Open, FileAccess.Read);
FileStream fs = new FileStream("Disk\\nonprog.dsk", FileMode.Open, FileAccess.Read);
_pack.Load(fs);
@@ -38,6 +38,7 @@ namespace Contralto.IO
set
{
_kDataWrite = value;
_kDataWriteLatch = true;
}
}
@@ -48,10 +49,13 @@ namespace Contralto.IO
{
_kAdr = value;
_recNo = 0;
_syncWordWritten = false;
// "In addition, it causes the head address bit to be loaded from KDATA[13]."
int newHead = (_kDataWrite & 0x4) >> 2;
_disk = ((_kDataWrite & 0x2) >> 1) ^ (_kAdr & 0x1);
if (newHead != _head)
{
// If we switch heads, we need to reload the sector
@@ -79,8 +83,24 @@ namespace Contralto.IO
(_kDataWrite & 0x2) >> 1,
(_kDataWrite & 0x1));
Log.Write(LogComponent.DiskController, " -Selected disk is {0}", ((_kDataWrite & 0x2) >> 1) ^ (_kAdr & 0x1));
Log.Write(LogComponent.DiskController, " -Selected disk is {0}", _disk);
if (((_kAdr & 0xc) >> 2) == 2 ||
((_kAdr & 0xc) >> 2) == 3)
{
Console.WriteLine("DATA WRITE");
}
if (_disk != 0)
{
Console.WriteLine("*** DISK 1 SELECTED ***");
}
if ((_kDataWrite & 0x1) != 0)
{
// Restore operation to cyl. 0:
InitSeek(0);
}
}
}
@@ -121,7 +141,8 @@ namespace Contralto.IO
{
get
{
// Bits 4-7 of KSTAT are always 1s.
// Bits 4-7 of KSTAT are always 1s (it's a shortcut allowing the disk microcode to write
// "-1" to bits 4-7 of the disk status word at 522 without extra code.)
return (ushort)(_kStat | (0x0f00));
}
set
@@ -139,12 +160,7 @@ namespace Contralto.IO
{
get { return _dataXfer; }
}
/// <summary>
/// This is a hack to see how the microcode expects INIT to work
/// </summary>
public int Cylinder
{
get { return _cylinder; }
@@ -179,9 +195,8 @@ namespace Contralto.IO
{
get
{
// TODO: verify if this is correct.
// Not ready if we're in the middle of a seek.
return (_kStat & 0x0040) == 0;
// TODO: verify what generates this signal
return true;
}
}
@@ -192,9 +207,11 @@ namespace Contralto.IO
_cylinder = _destCylinder = 0;
_sector = 0;
_head = 0;
_disk = 0;
_kStat = 0;
_kDataRead = 0;
_kDataWrite = 0;
_kDataWriteLatch = false;
_sendAdr = false;
_wdInhib = true;
@@ -202,6 +219,9 @@ namespace Contralto.IO
_wdInit = false;
_syncWordWritten = false;
_sectorModified = false;
_diskBitCounterEnable = false;
_sectorWordIndex = 0;
@@ -229,7 +249,14 @@ namespace Contralto.IO
}
private void SectorCallback(ulong timeNsec, ulong skewNsec, object context)
{
{
// Write last sector out if it was modified
if (_sectorModified)
{
CommitSector();
_sectorModified = false;
}
//
// Next sector; move to next sector and wake up Disk Sector task.
//
@@ -238,9 +265,10 @@ namespace Contralto.IO
_kStat = (ushort)((_kStat & 0x0fff) | (_sector << 12));
// Reset internal state machine for sector data
_sectorWordIndex = 0;
_sectorWordIndex = 0;
_syncWordWritten = false;
_kDataRead = 0;
_kDataRead = 0;
// Load new sector in
LoadSector();
@@ -346,6 +374,8 @@ namespace Contralto.IO
_kAdr = (ushort)(_kAdr << 2);
_recNo++;
_syncWordWritten = false;
if (_recNo > 3)
{
// sanity check for now
@@ -370,7 +400,12 @@ namespace Contralto.IO
Log.Write(LogComponent.DiskController, "STROBE: Seek initialized.");
_destCylinder = (_kDataWrite & 0x0ff8) >> 3;
InitSeek((_kDataWrite & 0x0ff8) >> 3);
}
private void InitSeek(int destCylinder)
{
_destCylinder = destCylinder;
// set "seek fail" bit based on selected cylinder (if out of bounds) and do not
// commence a seek if so.
@@ -395,7 +430,7 @@ namespace Contralto.IO
_seekEvent.TimestampNsec = _seekDuration;
_system.Scheduler.Schedule(_seekEvent);
Log.Write(LogComponent.DiskController, "Seek to {0} from {1} commencing. Will take {2} nsec.", _destCylinder, _cylinder, _seekDuration);
}
}
@@ -411,7 +446,7 @@ namespace Contralto.IO
//
double seekTimeMsec = 15.0 + 8.6 * Math.Sqrt(dt);
return (ulong)(seekTimeMsec * Conversion.MsecToNsec); // hack to speed things up
return (ulong)(seekTimeMsec * Conversion.MsecToNsec);
}
/// <summary>
@@ -465,16 +500,47 @@ namespace Contralto.IO
{
if (!_xferOff)
{
// Debugging: on a read/check, if we are overwriting a word that was never read by the
// microcode via KDATA, log it.
if (_debugRead && (((KADR & 0x00c0) >> 6) == 0 || ((KADR & 0x00c0) >> 6) == 1))
if (!IsWrite())
{
Console.WriteLine("--- missed sector word {0}({1}) ---", _sectorWordIndex, _kDataRead);
}
// Read operation:
// Debugging: on a read/check, if we are overwriting a word that was never read by the
// microcode via KDATA, log it.
if (_debugRead)
{
Console.WriteLine("--- missed sector word {0}({1}) ---", _sectorWordIndex, _kDataRead);
}
Log.Write(LogType.Verbose, LogComponent.DiskWordTask, "Sector {0} Word {1} read into KDATA", _sector, Conversion.ToOctal(diskWord));
_kDataRead = diskWord;
_debugRead = _sectorData[_sectorWordIndex].Type == CellType.Data;
Log.Write(LogType.Verbose, LogComponent.DiskWordTask, "Sector {0} Word {1} read into KDATA", _sector, Conversion.ToOctal(diskWord));
_kDataRead = diskWord;
_debugRead = _sectorData[_sectorWordIndex].Type == CellType.Data;
}
else
{
// Write
Log.Write(LogType.Normal, LogComponent.DiskController, "Sector {0} Word {1} (rec {2}) to be written with {3} from KDATA", _sector, _sectorWordIndex, _recNo, Conversion.ToOctal(_kDataWrite));
if (_kDataWriteLatch)
{
_kDataRead = _kDataWrite;
_kDataWriteLatch = false;
}
if (_syncWordWritten && _sectorWordIndex < _sectorData.Length)
{
if (_sectorData[_sectorWordIndex].Type == CellType.Data)
{
Console.WriteLine("Data written to data section.");
_sectorData[_sectorWordIndex].Data = _kDataWrite;
}
else
{
Console.WriteLine("Data written to non-data section.");
_sectorData[_sectorWordIndex].Data = _kDataWrite;
}
_sectorModified = true;
}
}
}
if (!_wdInhib)
@@ -489,16 +555,38 @@ namespace Contralto.IO
// the clock. This occurs late in the cycle so that the NEXT word
// (not the sync word) is actually read. TODO: this should only happen on reads.
//
if (!_wffo && diskWord == 1)
if (!IsWrite() && !_wffo && diskWord == 1)
{
_diskBitCounterEnable = true;
}
else if (IsWrite() && _wffo && _kDataWrite == 1 && !_syncWordWritten)
{
Log.Write(LogType.Normal, LogComponent.DiskController, "Sector {0} Sync Word {1} (rec {2}) written.", _sector, _sectorWordIndex, _recNo);
_syncWordWritten = true;
// "Adjust" the write index to the start of the data area for the current record.
// This is cheating.
switch(_recNo)
{
case 0:
_sectorWordIndex = _headerOffset;
break;
case 1:
_sectorWordIndex = _labelOffset;
break;
case 2:
_sectorWordIndex = _dataOffset;
break;
}
}
if (bWakeup)
{
Log.Write(LogType.Verbose, LogComponent.DiskWordTask, "Word task awoken for word {0}.", _sectorWordIndex);
_system.CPU.WakeupTask(TaskType.DiskWord);
}
}
// Last, move to the next word.
_sectorWordIndex++;
@@ -549,6 +637,37 @@ namespace Contralto.IO
}
/// <summary>
/// Commits modified sector data back to the emulated disk.
/// Intended to be called at the end of the sector / beginning of the next.
/// TODO: we should modify this so that checksums are persisted, possibly...
/// </summary>
private void CommitSector()
{
DiabloDiskSector sector = _pack.GetSector(_cylinder, _head, _sector);
// Header (2 words data, 1 word cksum)
for (int i = _headerOffset + 1, j = 1; i < _headerOffset + 3; i++, j--)
{
// actual data to be loaded from disk / cksum calculated
sector.Header[j] = _sectorData[i].Data;
}
// Label (8 words data, 1 word cksum)
for (int i = _labelOffset + 1, j = 7; i < _labelOffset + 9; i++, j--)
{
// actual data to be loaded from disk / cksum calculated
sector.Label[j] = _sectorData[i].Data;
}
// sector data (256 words data, 1 word cksum)
for (int i = _dataOffset + 1, j = 255; i < _dataOffset + 257; i++, j--)
{
// actual data to be loaded from disk / cksum calculated
sector.Data[j] = _sectorData[i].Data;
}
}
private void InitSector()
{
// Fill in sector with default data (basically, fill in non-data areas).
@@ -576,7 +695,7 @@ namespace Contralto.IO
_sectorData[_dataOffset] = new DataCell(1, CellType.Sync);
// read-postamble
for (int i = _dataOffset + 257; i < _sectorWordCount;i++)
for (int i = _dataOffset + 258; i < _sectorWordCount;i++)
{
_sectorData[i] = new DataCell(0, CellType.Gap);
}
@@ -606,8 +725,14 @@ namespace Contralto.IO
return checksum;
}
private bool IsWrite()
{
return ((_kAdr & 0x00c0) >> 6) == 2 || ((_kAdr & 0x00c0) >> 6) == 3;
}
private ushort _kDataRead;
private ushort _kDataWrite;
private bool _kDataWriteLatch;
private ushort _kAdr;
private ushort _kCom;
private ushort _kStat;
@@ -634,12 +759,18 @@ namespace Contralto.IO
private int _head;
private int _sector;
// Selected disk
private int _disk;
// bit clock flag
private bool _diskBitCounterEnable;
// WDINIT signal
private bool _wdInit;
private bool _syncWordWritten;
private bool _sectorModified;
// Sector timing. Based on table on pg. 43 of the Alto Hardware Manual
// From altoconsts23.mu: [all constants in octal, for reference]