mirror of
https://github.com/JorjBauer/aiie.git
synced 2024-08-28 01:29:03 +00:00
761 lines
22 KiB
C++
761 lines
22 KiB
C++
#include "diskii.h"
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#ifdef TEENSYDUINO
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#include <Arduino.h>
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#else
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#include <unistd.h>
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#include <fcntl.h>
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#include <stdlib.h>
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#include <string.h>
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#include <time.h>
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#endif
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#include "applemmu.h" // for FLOATING
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#include "globals.h"
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#include "appleui.h"
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#include "diskii-rom.h"
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#define DISKIIMAGIC 0xAA
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// how many CPU cycles do we wait to spin down the disk drive? 1023000 == 1 second
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#define SPINDOWNDELAY (1023000)
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// 10 second delay before flushing
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#define FLUSHDELAY (1023000 * 10)
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DiskII::DiskII(AppleMMU *mmu)
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{
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this->mmu = mmu;
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curPhase[0] = curPhase[1] = 0;
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curHalfTrack[0] = curHalfTrack[1] = 0;
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curWozTrack[0] = curWozTrack[1] = 0xFF;
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writeMode = false;
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writeProt = false; // FIXME: expose an interface to this
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readWriteLatch = 0x00;
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sequencer = 0;
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dataRegister = 0;
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driveSpinupCycles[0] = driveSpinupCycles[1] = 0;
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deliveredDiskBits[0] = deliveredDiskBits[1] = 0;
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disk[0] = disk[1] = NULL;
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diskIsSpinningUntil[0] = diskIsSpinningUntil[1] = 0;
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flushAt[0] = flushAt[1] = 0;
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selectedDisk = 0;
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}
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DiskII::~DiskII()
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{
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}
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bool DiskII::Serialize(int8_t fd)
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{
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uint8_t buf[23] = { DISKIIMAGIC,
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readWriteLatch,
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sequencer,
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dataRegister,
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writeMode,
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writeProt,
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selectedDisk };
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if (g_filemanager->write(fd, buf, 7) != 7) {
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return false;
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}
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for (int i=0; i<2; i++) {
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uint8_t ptr = 0;
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buf[ptr++] = curHalfTrack[i];
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buf[ptr++] = curWozTrack[i];
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buf[ptr++] = curPhase[i];
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buf[ptr++] = ((driveSpinupCycles[i] >> 56) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] >> 48) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] >> 40) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] >> 32) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] >> 24) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] >> 16) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] >> 8) & 0xFF);
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buf[ptr++] = ((driveSpinupCycles[i] ) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 56) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 48) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 40) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 32) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 24) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 16) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] >> 8) & 0xFF);
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buf[ptr++] = ((deliveredDiskBits[i] ) & 0xFF);
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buf[ptr++] = (diskIsSpinningUntil[i] >> 24) & 0xFF;
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buf[ptr++] = (diskIsSpinningUntil[i] >> 16) & 0xFF;
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buf[ptr++] = (diskIsSpinningUntil[i] >> 8) & 0xFF;
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buf[ptr++] = (diskIsSpinningUntil[i] ) & 0xFF;
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// Safety check: keeping the hard-coded 23 and comparing against ptr.
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// If we change the 23, also need to change the size of buf[] above
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if (g_filemanager->write(fd, buf, 23) != ptr) {
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return false;
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}
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if (disk[i]) {
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// Make sure we have flushed the disk images
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disk[i]->flush();
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flushAt[i] = 0; // and there's no need to re-flush them now
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buf[0] = 1;
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if (g_filemanager->write(fd, buf, 1) != 1)
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return false;
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// FIXME: this ONLY works for builds using the filemanager to read
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// the disk image, so it's broken until we port Woz to do that!
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const char *fn = disk[i]->diskName();
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if (g_filemanager->write(fd, fn, strlen(fn)+1) != strlen(fn)+1) // include null terminator
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return false;
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if (!disk[i]->Serialize(fd))
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return false;
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} else {
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buf[0] = 0;
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if (g_filemanager->write(fd, buf, 0) != 1)
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return false;
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}
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}
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buf[0] = DISKIIMAGIC;
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if (g_filemanager->write(fd, buf, 1) != 1)
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return false;
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return true;
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}
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bool DiskII::Deserialize(int8_t fd)
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{
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uint8_t buf[23];
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if (g_filemanager->read(fd, buf, 7) != 7)
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return false;
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if (buf[0] != DISKIIMAGIC)
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return false;
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readWriteLatch = buf[1];
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sequencer = buf[2];
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dataRegister = buf[3];
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writeMode = buf[4];
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writeProt = buf[5];
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selectedDisk = buf[6];
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for (int i=0; i<2; i++) {
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uint8_t ptr = 0;
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if (g_filemanager->read(fd, buf, 23) != 23)
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return false;
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curHalfTrack[i] = buf[ptr++];
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curWozTrack[i] = buf[ptr++];
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curPhase[i] = buf[ptr++];
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driveSpinupCycles[i] = buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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driveSpinupCycles[i] <<= 8; driveSpinupCycles[i] |= buf[ptr++];
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deliveredDiskBits[i] = buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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deliveredDiskBits[i] <<= 8; deliveredDiskBits[i] |= buf[ptr++];
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diskIsSpinningUntil[i] = buf[ptr++];
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diskIsSpinningUntil[i] <<= 8; diskIsSpinningUntil[i] |= buf[ptr++];
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diskIsSpinningUntil[i] <<= 8; diskIsSpinningUntil[i] |= buf[ptr++];
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diskIsSpinningUntil[i] <<= 8; diskIsSpinningUntil[i] |= buf[ptr++];
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if (disk[i])
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delete disk[i];
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if (g_filemanager->read(fd, buf, 1) != 1)
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return false;
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if (buf[0]) {
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disk[i] = new WozSerializer();
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ptr = 0;
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while (1) {
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if (g_filemanager->read(fd, &buf[ptr++], 1) != 1)
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return false;
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if (buf[ptr-1] == 0)
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break;
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}
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if (buf[0]) {
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// Important we don't read all the tracks, so we can also flush
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// writes back to the fd...
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disk[i]->readFile((char *)buf, false, T_AUTO); // FIXME error checking
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} else {
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// ERROR: there's a disk but we don't have the path to its image?
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return false;
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}
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if (!disk[i]->Deserialize(fd))
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return false;
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} else {
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disk[i] = NULL;
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}
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}
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if (g_filemanager->read(fd, buf, 1) != 1)
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return false;
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if (buf[0] != DISKIIMAGIC)
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return false;
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return true;
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}
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void DiskII::Reset()
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{
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curPhase[0] = curPhase[1] = 0;
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curHalfTrack[0] = curHalfTrack[1] = 0;
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writeMode = false;
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writeProt = false; // FIXME: expose an interface to this
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readWriteLatch = 0x00;
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ejectDisk(0);
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ejectDisk(1);
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}
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void DiskII::driveOff()
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{
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if (diskIsSpinningUntil[selectedDisk] == -1) {
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diskIsSpinningUntil[selectedDisk] = g_cpu->cycles + SPINDOWNDELAY; // 1 second lag
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if (diskIsSpinningUntil[selectedDisk] == -1 ||
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diskIsSpinningUntil[selectedDisk] == 0)
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diskIsSpinningUntil[selectedDisk] = 2; // fudge magic numbers; 0 is "off" and -1 is "forever".
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// The drive-is-on-indicator is turned off later, when the disk
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// actually spins down.
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}
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if (disk[selectedDisk]) {
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flushAt[selectedDisk] = g_cpu->cycles + FLUSHDELAY;
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if (flushAt[selectedDisk] == 0)
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flushAt[selectedDisk] = 1; // fudge magic number; 0 is "don't flush"
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}
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}
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void DiskII::driveOn()
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{
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if (diskIsSpinningUntil[selectedDisk] != -1) {
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// If the drive isn't already spinning, then start keeping track of how
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// many bits we've delivered (so we can honor the disk bit-delivery time
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// that might be in the Woz disk image).
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driveSpinupCycles[selectedDisk] = g_cpu->cycles;
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deliveredDiskBits[selectedDisk] = 0;
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diskIsSpinningUntil[selectedDisk] = -1; // magic "forever"
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}
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// FIXME: does the sequencer get reset? Maybe if it's the selected disk? Or no?
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// sequencer = 0;
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g_ui->drawOnOffUIElement(UIeDisk1_activity + selectedDisk, true); // FIXME: do we really want to update the UI from inside this thread?
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}
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uint8_t DiskII::readSwitches(uint8_t s)
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{
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switch (s) {
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case 0x00: // change stepper motor phase
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break;
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case 0x01:
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setPhase(0);
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break;
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case 0x02:
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break;
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case 0x03:
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setPhase(1);
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break;
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case 0x04:
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break;
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case 0x05:
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setPhase(2);
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break;
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case 0x06: // 3 off
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break;
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case 0x07: // 3 on
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setPhase(3);
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break;
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case 0x08: // drive off
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driveOff();
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break;
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case 0x09: // drive on
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driveOn();
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break;
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case 0x0A: // select drive 1
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select(0);
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break;
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case 0x0B: // select drive 2
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select(1);
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break;
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case 0x0C: // shift one read or write byte
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readWriteLatch = readOrWriteByte();
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if (readWriteLatch & 0x80) {
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// static uint32_t lastC = 0;
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// printf("%u: read data\n", g_cpu->cycles - lastC);
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// lastC = g_cpu->cycles;
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if (!(sequencer & 0x80)) {
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// printf("SEQ RESET EARLY [1]\n");
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}
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sequencer = 0;
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}
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break;
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case 0x0D: // load data register (latch)
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// This is complex and incomplete. cf. Logic State Sequencer,
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// UTA2E, p. 9-14
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if (!writeMode) {
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if (isWriteProtected())
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readWriteLatch |= 0x80;
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else
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readWriteLatch &= 0x7F;
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}
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if (!(sequencer & 0x80)) {
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// printf("SEQ RESET EARLY [2]\n");
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}
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sequencer = 0;
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break;
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case 0x0E: // set read mode
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setWriteMode(false);
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break;
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case 0x0F: // set write mode
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setWriteMode(true);
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break;
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}
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// Any even address read returns the readWriteLatch (UTA2E Table 9.1,
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// p. 9-12, note 2)
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return (s & 1) ? FLOATING : readWriteLatch;
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}
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void DiskII::writeSwitches(uint8_t s, uint8_t v)
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{
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switch (s) {
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case 0x00: // change stepper motor phase
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break;
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case 0x01:
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setPhase(0);
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break;
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case 0x02:
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break;
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case 0x03:
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setPhase(1);
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break;
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case 0x04:
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break;
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case 0x05:
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setPhase(2);
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break;
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case 0x06: // 3 off
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break;
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case 0x07: // 3 on
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setPhase(3);
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break;
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case 0x08: // drive off
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driveOff();
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break;
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case 0x09: // drive on
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driveOn();
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break;
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case 0x0A: // select drive 1
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select(0);
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break;
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case 0x0B: // select drive 2
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select(1);
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break;
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case 0x0C: // shift one read or write byte
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if (readOrWriteByte() & 0x80) {
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if (!(sequencer & 0x80)) {
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// printf("SEQ RESET EARLY [3]\n");
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}
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sequencer = 0;
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}
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break;
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case 0x0D: // drive write
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break;
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case 0x0E: // set read mode
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setWriteMode(false);
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break;
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case 0x0F: // set write mode
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setWriteMode(true);
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break;
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}
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// All writes update the latch
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if (writeMode) {
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readWriteLatch = v;
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}
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}
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/* The Disk ][ has a stepper motor that moves the head across the tracks.
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* Switches 0-7 turn off and on the four different magnet phases; pulsing
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* from (e.g.) phase 0 to phase 1 makes the motor move up a track, and
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* (e.g.) phase 1 to phase 0 makes the motor move down a track.
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*
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* Except that's not quite true: the stepper actually moves the head a
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* _half_ track.
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*
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* This is a very simplified version of the stepper motor code. In theory,
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* we should keep track of all 4 phase magnets; and then only move up or down
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* a half track when two adjacent motors are on (not three adjacent motors;
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* and not two opposite motors). But that physical characteristic isn't
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* important for most diskettes, and our image formats aren't likely to
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* be able to provide appropriate half-track data to the programs that played
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* tricks with these half-tracks (for copy protection or whatever).
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*
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* This setPhase is only called when turning *on* a phase. It's assumed that
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* something is turning *off* the phases correctly; and that the combination
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* of the previous phase that was on and the current phase that's being turned
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* on are reliable enough to determine direction.
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*
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* The _phase_delta array is four sets of offsets - one for each
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* current phase, detailing what the step will be given the next
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* phase. This kind of emulates the messiness of going from phase 0
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* to 2 -- it's going to move forward two half-steps -- but then doing
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* the same thing again is just going to move you back two half-steps...
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*
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*/
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void DiskII::setPhase(uint8_t phase)
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{
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const int8_t _phase_delta[16] = { 0, 1, 2, -1, // prev phase 0 -> 0/1/2/3
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-1, 0, 1, 2, // prev phase 1 -> 0/1/2/3
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-2, -1, 0, 1, // prev phase 2 -> 0/1/2/3
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1, -2, -1, 0 // prev phase 3 -> 0/1/2/3
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};
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int8_t prevPhase = curPhase[selectedDisk];
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int8_t prevHalfTrack = curHalfTrack[selectedDisk];
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curHalfTrack[selectedDisk] += _phase_delta[(prevPhase * 4) + phase];
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curPhase[selectedDisk] = phase;
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// Cap at 35 tracks (a normal disk size). Some drives let you go farther,
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// and we could support that by increasing this limit - but the images
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// would be different too, so there would be more work to abstract out...
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if (curHalfTrack[selectedDisk] > 35 * 2 - 1) {
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curHalfTrack[selectedDisk] = 35 * 2 - 1;
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}
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// Don't go past the innermost track, of course.
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if (curHalfTrack[selectedDisk] < 0) {
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curHalfTrack[selectedDisk] = 0;
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// recalibrate! This is where the fun noise goes DaDaDaDaDaDaDaDaDa
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}
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if (curHalfTrack[selectedDisk] != prevHalfTrack) {
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if (disk[selectedDisk]) {
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curWozTrack[selectedDisk] = disk[selectedDisk]->dataTrackNumberForQuarterTrack(curHalfTrack[selectedDisk]*2);
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} else {
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curWozTrack[selectedDisk] = 0;
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}
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}
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}
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bool DiskII::isWriteProtected()
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{
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return (writeProt ? 0xFF : 0x00);
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}
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int64_t DiskII::calcExpectedBits()
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{
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// If the disk isn't spinning, then it can't be expected to deliver data
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if (!diskIsSpinningUntil[selectedDisk])
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return 0;
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// Handle potential messy counter rollover
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if (driveSpinupCycles[selectedDisk] > g_cpu->cycles) {
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driveSpinupCycles[selectedDisk] = g_cpu->cycles-1;
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if (driveSpinupCycles[selectedDisk] == 0) // avoid sitting on 0
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driveSpinupCycles[selectedDisk]++;
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}
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uint32_t cyclesPassed = g_cpu->cycles - driveSpinupCycles[selectedDisk];
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// This constant defines how fast the disk drive "spins".
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// 4.0 is good for DOS 3.3 writes, and reads as 205ms in
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// Copy 2+'s drive speed verifier.
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// 3.99: 204.5ms
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// 3.90: 199.9ms
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// 3.91: 200.5ms
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// 3.51: 176ms, and is too fast for DOS to write properly.
|
|
uint64_t expectedDiskBits = (float)cyclesPassed / 3.90;
|
|
|
|
return expectedDiskBits - deliveredDiskBits[selectedDisk];
|
|
}
|
|
|
|
void DiskII::setWriteMode(bool enable)
|
|
{
|
|
if (enable) {
|
|
// At this point we need to update the track pointer so we know
|
|
// where we're going to start writing bits.
|
|
|
|
int64_t db = calcExpectedBits();
|
|
if (db > 0) {
|
|
// make sure the disk is at the right point for our program counter's time
|
|
// before we start writing data.
|
|
deliveredDiskBits[selectedDisk] += db;
|
|
while (db) {
|
|
sequencer <<= 1;
|
|
sequencer |= disk[selectedDisk]->nextDiskBit(curWozTrack[selectedDisk]);
|
|
db--;
|
|
}
|
|
}
|
|
}
|
|
writeMode = enable;
|
|
}
|
|
|
|
static uint8_t _lc(char c)
|
|
{
|
|
if (c >= 'A' && c <= 'Z') {
|
|
c = c - 'A' + 'a';
|
|
}
|
|
return c;
|
|
}
|
|
|
|
static bool _endsWithI(const char *s1, const char *s2)
|
|
{
|
|
if (strlen(s2) > strlen(s1)) {
|
|
return false;
|
|
}
|
|
|
|
const char *p = &s1[strlen(s1)-1];
|
|
int16_t l = strlen(s2)-1;
|
|
while (l >= 0) {
|
|
if (_lc(*p--) != _lc(s2[l]))
|
|
return false;
|
|
l--;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void DiskII::insertDisk(int8_t driveNum, const char *filename, bool drawIt)
|
|
{
|
|
ejectDisk(driveNum);
|
|
|
|
disk[driveNum] = new WozSerializer();
|
|
// intentionally 'false' (see above call to readFile)
|
|
if (!disk[driveNum]->readFile(filename, false, T_AUTO)) {
|
|
delete disk[driveNum];
|
|
disk[driveNum] = NULL;
|
|
return;
|
|
}
|
|
|
|
curWozTrack[driveNum] = disk[driveNum]->dataTrackNumberForQuarterTrack(curHalfTrack[driveNum]*2);
|
|
|
|
if (drawIt)
|
|
g_ui->drawOnOffUIElement(UIeDisk1_state + driveNum, false);
|
|
}
|
|
|
|
void DiskII::ejectDisk(int8_t driveNum)
|
|
{
|
|
if (disk[driveNum]) {
|
|
disk[driveNum]->flush();
|
|
flushAt[driveNum] = 0;
|
|
delete disk[driveNum];
|
|
disk[driveNum] = NULL;
|
|
g_ui->drawOnOffUIElement(UIeDisk1_state + driveNum, true);
|
|
}
|
|
}
|
|
|
|
void DiskII::select(int8_t which)
|
|
{
|
|
if (which != 0 && which != 1)
|
|
return;
|
|
|
|
if (which != selectedDisk) {
|
|
if (diskIsSpinningUntil[selectedDisk] == -1) {
|
|
// FIXME: I'm not sure what the right behavior is here (read
|
|
// UTA2E and see if the state diagrams show the right
|
|
// behavior). This spins it down immediately based on something
|
|
// I read about the duoDisk not having both motors on
|
|
// simultaneously.
|
|
diskIsSpinningUntil[selectedDisk] = 0;
|
|
// FIXME: consume any disk bits that need to be consumed, and
|
|
// spin it down
|
|
g_ui->drawOnOffUIElement(UIeDisk1_activity + selectedDisk, false); // FIXME: queue for later drawing?
|
|
|
|
// Spin up the other one though
|
|
diskIsSpinningUntil[which] = -1;
|
|
g_ui->drawOnOffUIElement(UIeDisk1_activity + which, false); // FIXME: queue for later drawing?
|
|
}
|
|
|
|
// Queue flushing the cache of the disk that's no longer selected
|
|
if (disk[selectedDisk]) {
|
|
flushAt[selectedDisk] = g_cpu->cycles + FLUSHDELAY;
|
|
if (flushAt[selectedDisk] == 0)
|
|
flushAt[selectedDisk] = 1; // fudge magic number; 0 is "don't flush"
|
|
}
|
|
|
|
// set the selected disk drive
|
|
selectedDisk = which;
|
|
|
|
// FIXME: does this reset the sequencer?
|
|
sequencer = 0;
|
|
}
|
|
|
|
// Update the current woz track for the given disk drive
|
|
if (disk[selectedDisk]) {
|
|
curWozTrack[selectedDisk] =
|
|
disk[selectedDisk]->dataTrackNumberForQuarterTrack(curHalfTrack[selectedDisk]*2);
|
|
}
|
|
}
|
|
|
|
uint8_t DiskII::readOrWriteByte()
|
|
{
|
|
if (!disk[selectedDisk]) {
|
|
//printf("reading from uninserted disk\n");
|
|
return 0xFF;
|
|
}
|
|
|
|
int32_t bitsToDeliver;
|
|
|
|
if (diskIsSpinningUntil[selectedDisk] < g_cpu->cycles) {
|
|
// Uum, disk isn't spinning?
|
|
goto done;
|
|
}
|
|
|
|
bitsToDeliver = calcExpectedBits();
|
|
|
|
if (writeMode && !writeProt) {
|
|
// It's a write request.
|
|
|
|
// Write requests from DOS 3.3 start with 40 self-sync bytes
|
|
// (cf. Beneath Apple DOS, p.3-8 and 3-9). These 0XFF bytes are
|
|
// written in a 40-cycle loop, where a bit is written every 4
|
|
// cycles; it intentionally lets 2 0-bits slip in there to
|
|
// provide the self-sync pattern.
|
|
//
|
|
// So the timing here is important. Figure out how many bits
|
|
// should have been laid down to the track, and those are 0s.
|
|
|
|
int64_t expectedBits = calcExpectedBits();
|
|
while (expectedBits > 0) {
|
|
disk[selectedDisk]->writeNextWozBit(curWozTrack[selectedDisk], 0);
|
|
expectedBits--;
|
|
deliveredDiskBits[selectedDisk]++;
|
|
}
|
|
|
|
disk[selectedDisk]->writeNextWozByte(curWozTrack[selectedDisk], readWriteLatch);
|
|
deliveredDiskBits[selectedDisk] += 8;
|
|
goto done;
|
|
}
|
|
|
|
if (bitsToDeliver > 0) {
|
|
// We're expected to deliver some bits to the Disk II sequencer.
|
|
// Instead of piecemeal delivering a small number of bits (which we
|
|
// could do, but it's kinda busywork) - instead, we'll do one of two
|
|
// possible things.
|
|
//
|
|
// The first: if we're expecting a small number of bits to be delivered,
|
|
// then we'll grab the next byte from the nibble stream and return it.
|
|
// This itself has three possible cases -
|
|
// (a) we should be delivering less than a full byte, but we're
|
|
// actually going to deliver a full byte. bitsToDeliver will
|
|
// become negative, because we're delivering these too early.
|
|
// The next call will probably see that it has nothing to deliver
|
|
// and, as long as the disk image we're using doesn't have a
|
|
// really fine tolerance on the delivery rate of the bits,
|
|
// it will all come out in the wash.
|
|
// (b) we should be delivering exactly a byte, and we're doing the
|
|
// absolute right thing.
|
|
// (c) we are more than 1 byte, but less than 2 bytes, behind. If
|
|
// this is the case, we're probably making up for a timing
|
|
// problem in this code - where the bits would now have been
|
|
// lost. By returning the first byte that we found, we're hoping
|
|
// that the next call will be closer to on time, and we will
|
|
// eventually catch back up to the stream. Hopefully this makes
|
|
// the stream a little more resilient - and the error isn't
|
|
// so far off that the reader notices something is weird on the
|
|
// timing. (Standard RWTS doesn't, but some copy protection
|
|
// might.)
|
|
if (bitsToDeliver < 16) {
|
|
while (bitsToDeliver > -16 && ((sequencer & 0x80) == 0)) {
|
|
sequencer <<= 1;
|
|
sequencer |= disk[selectedDisk]->nextDiskBit(curWozTrack[selectedDisk]);
|
|
bitsToDeliver--;
|
|
deliveredDiskBits[selectedDisk]++;
|
|
}
|
|
goto done;
|
|
}
|
|
|
|
// If we reach here, we're throwing away a bunch of missed data.
|
|
// This might be normal (where the machine wasn't listening for the data),
|
|
// or it might be exceptional (something wrong with the tuning of data
|
|
// delivery, based on the magic constant in expectedDiskBits above)...
|
|
deliveredDiskBits[selectedDisk] += bitsToDeliver;
|
|
while (bitsToDeliver) {
|
|
sequencer <<= 1;
|
|
sequencer |= disk[selectedDisk]->nextDiskBit(curWozTrack[selectedDisk]);
|
|
bitsToDeliver--;
|
|
}
|
|
}
|
|
|
|
|
|
done:
|
|
return sequencer;
|
|
}
|
|
|
|
const char *DiskII::DiskName(int8_t num)
|
|
{
|
|
if (disk[num]) {
|
|
return disk[num]->diskName();
|
|
}
|
|
|
|
// Nothing inserted in that drive
|
|
return "";
|
|
}
|
|
|
|
void DiskII::loadROM(uint8_t *toWhere)
|
|
{
|
|
#ifdef TEENSYDUINO
|
|
Serial.println("loading DiskII rom");
|
|
for (uint16_t i=0; i<=0xFF; i++) {
|
|
toWhere[i] = pgm_read_byte(&romData[i]);
|
|
}
|
|
#else
|
|
printf("loading DiskII rom\n");
|
|
memcpy(toWhere, romData, 256);
|
|
#endif
|
|
}
|
|
|
|
void DiskII::maintenance(uint32_t cycle)
|
|
{
|
|
// Handle spin-down for the drive. Drives stay on for a second after
|
|
// the stop was noticed.
|
|
for (int i=0; i<2; i++) {
|
|
if (diskIsSpinningUntil[i] &&
|
|
g_cpu->cycles > diskIsSpinningUntil[i]) {
|
|
// Stop the given disk drive spinning
|
|
diskIsSpinningUntil[i] = 0;
|
|
// FIXME: consume any disk bits that need to be consumed, and spin it down
|
|
g_ui->drawOnOffUIElement(UIeDisk1_activity + i, false); // FIXME: queue for later drawing?
|
|
}
|
|
|
|
if (flushAt[i] &&
|
|
g_cpu->cycles > flushAt[i]) {
|
|
if (disk[i]) {
|
|
disk[i]->flush();
|
|
}
|
|
flushAt[i] = 0;
|
|
}
|
|
|
|
}
|
|
}
|