mirror of
https://github.com/livingcomputermuseum/ContrAlto.git
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f849b795a6
1) The Orbit microcode occasionally expects to be able to do a double-word read in cycles 6 and 7 instead of the usual 5 and 6. 2) The double-word logic incorrectly handles several species of overlapped read/writes, which Spruce's layout microcode uses. As a result, Spruce now works, as do the Smalltalk-80 images. Several tweaks to microcode disassembly (still rough). Completed Orbit / Dover ROS / Dover Print Engine emulation. Still some rough edges; it works and can create PDF output. Tweaked Disk Controller's Restore operation, it is now more accurate though wasn't causing any noticable issues.
113 lines
3.7 KiB
C#
113 lines
3.7 KiB
C#
/*
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This file is part of ContrAlto.
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ContrAlto is free software: you can redistribute it and/or modify
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it under the terms of the GNU Affero General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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ContrAlto is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Affero General Public License for more details.
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You should have received a copy of the GNU Affero General Public License
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along with ContrAlto. If not, see <http://www.gnu.org/licenses/>.
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*/
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using Contralto.CPU;
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using Contralto.Logging;
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using Contralto.Memory;
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namespace Contralto.IO
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{
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/// <summary>
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/// Implements the Organ Keyboard interface used by the ST-74
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/// Music System. Very little is known about the hardware at this time,
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/// so most of this is speculation or based on disassembly/reverse-engineering
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/// of the music system code.
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///
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/// This is currently a stub that implements the bare minimum to make the
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/// music system think there's a keyboard attached to the system.
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/// </summary>
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public class OrganKeyboard : IMemoryMappedDevice
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{
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public OrganKeyboard(AltoSystem system)
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{
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_system = system;
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Reset();
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}
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public void Reset()
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{
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//
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// Initialize keyboard registers.
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// Based on disassembly of the Nova code that drives the keyboard
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// interface, the top 6 bits are active low.
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//
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for (int i = 0; i < 16; i++)
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{
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_keyData[i] = (ushort)(0xfc00);
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}
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}
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/// <summary>
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/// Reads a word from the specified address.
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/// </summary>
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/// <param name="address"></param>
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/// <param name="extendedMemory"></param>
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/// <returns></returns>
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public ushort Read(int address, TaskType task, bool extendedMemory)
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{
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Log.Write(LogType.Verbose, LogComponent.Organ, "Organ read from {0} by task {1} (bank {2}), Nova PC {3}",
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Conversion.ToOctal(address),
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task,
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UCodeMemory.GetBank(task),
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Conversion.ToOctal(_system.CPU.R[6]));
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return _keyData[address - 0xfe60];
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}
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/// <summary>
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/// Writes a word to the specified address.
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/// </summary>
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/// <param name="address"></param>
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/// <param name="data"></param>
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public void Load(int address, ushort data, TaskType task, bool extendedMemory)
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{
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// The registers are write-only as far as I've been able to ascertain.
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Log.Write(LogType.Verbose, LogComponent.Organ, "Unexpected organ write to {0} ({1}) by task {2} (bank {3})",
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Conversion.ToOctal(address),
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Conversion.ToOctal(data),
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task,
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UCodeMemory.GetBank(task));
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}
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/// <summary>
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/// Specifies the range (or ranges) of addresses decoded by this device.
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/// </summary>
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public MemoryRange[] Addresses
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{
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get { return _addresses; }
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}
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/// <summary>
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/// From: http://bitsavers.org/pdf/xerox/alto/memos_1975/Reserved_Alto_Memory_Locations_Jan75.pdf
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///
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/// #177140 - #177157: Organ Keyboard (Organ Hardware - Kaehler)
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/// </summary>
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private readonly MemoryRange[] _addresses =
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{
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new MemoryRange(0xfe60, 0xfe6f),
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};
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private ushort[] _keyData = new ushort[16];
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private AltoSystem _system;
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}
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} |