ShuriZma
/
BizHawk
mirror of https://github.com/TASEmulators/BizHawk.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

C64: Use proper sector gaps based on density when converting from D64.

This commit is contained in:
SaxxonPike 2019-07-04 00:02:28 -05:00
parent e74dfe15a8
commit ceb1338459
2 changed files with 84 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
BizHawk.Emulation.Cores/Computers/Commodore64/Media/D64.cs
View File

@ -1,6 +1,7 @@
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
namespace BizHawk.Emulation.Cores.Computers.Commodore64.Media
{
@ -63,6 +64,11 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64.Media
6250, 6666, 7142, 7692
};
private static readonly int[] StandardSectorGapLength =
{
9, 19, 13, 10
};
private static byte Checksum(byte[] source)
{
var count = source.Length;
@ -76,7 +82,7 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64.Media
return result;
}
private static byte[] ConvertSectorToGcr(byte[] source, byte sectorNo, byte trackNo, byte formatA, byte formatB, out int bitsWritten)
private static byte[] ConvertSectorToGcr(byte[] source, byte sectorNo, byte trackNo, byte formatA, byte formatB, int gapLength, out int bitsWritten)
{
using (var mem = new MemoryStream())
{
@ -96,7 +102,7 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64.Media
writer.Write(new byte[] { 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55 }); // gap
writer.Write(new byte[] { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }); // sync
writer.Write(EncodeGcr(writtenData)); // data
writer.Write(new byte[] { 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55 }); // gap
writer.Write(Enumerable.Repeat((byte)0x55, gapLength).ToArray()); // gap
bitsWritten = (int)mem.Length * 8;
@ -185,7 +191,7 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64.Media
{
int bitsWritten;
var sectorData = reader.ReadBytes(256);
var diskData = ConvertSectorToGcr(sectorData, (byte)j, (byte)(i + 1), 0xA0, 0xA0, out bitsWritten);
var diskData = ConvertSectorToGcr(sectorData, (byte)j, (byte)(i + 1), 0xA0, 0xA0, StandardSectorGapLength[DensityTable[i]], out bitsWritten);
trackMem.Write(diskData, 0, diskData.Length);
trackLengthBits += bitsWritten;
}

75
BizHawk.Emulation.Cores/Computers/Commodore64/Media/G64.cs
View File

@ -63,5 +63,80 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64.Media
return new Disk(84);
}
}
public static byte[] Write(IList<byte[]> trackData, IList<int> trackNumbers, IList<int> trackDensities)
{
const byte version = 0;
const byte trackCount = 84;
const int headerLength = 0xC;
const byte dataFillerValue = 0xFF;
var trackMaxLength = (ushort)Math.Max(7928, trackData.Max(d => d.Length));
using (var mem = new MemoryStream())
{
var writer = new BinaryWriter(mem);
// header ID
writer.Write("GCR-1541".ToCharArray());
// version #
writer.Write(version);
// tracks in the image
writer.Write(trackCount);
// maximum track size in bytes
writer.Write(trackMaxLength);
// combine track data
var offsets = new List<int>();
var densities = new List<int>();
using (var trackMem = new MemoryStream())
{
var trackMemWriter = new BinaryWriter(trackMem);
for (var i = 0; i < trackCount; i++)
{
if (trackNumbers.Contains(i))
{
var trackIndex = trackNumbers.IndexOf(i);
offsets.Add((int)trackMem.Length);
densities.Add(trackDensities[trackIndex]);
var data = trackData[trackIndex];
var buffer = Enumerable.Repeat(dataFillerValue, trackMaxLength).ToArray();
var dataBytes = data.Select(d => unchecked((byte)d)).ToArray();
Array.Copy(dataBytes, buffer, dataBytes.Length);
trackMemWriter.Write((ushort)dataBytes.Length);
trackMemWriter.Write(buffer);
}
else
{
offsets.Add(-1);
densities.Add(0);
}
}
trackMemWriter.Flush();
// offset table
foreach (var offset in offsets.Select(o => o >= 0 ? o + headerLength + trackCount * 8 : 0))
{
writer.Write(offset);
}
// speed zone data
foreach (var density in densities)
{
writer.Write(density);
}
// track data
writer.Write(trackMem.ToArray());
}
writer.Flush();
return mem.ToArray();
}
}
}
}