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Starts trying to get a bit more rigorous about collected meanings.

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This commit is contained in:
Thomas Harte 2019-06-13 22:48:10 -04:00
parent bde975a3b9
commit cc7226ae9f
1 changed files with 19 additions and 11 deletions
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30
Components/DiskII/IWM.cpp
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@ -58,7 +58,7 @@ uint8_t IWM::read(int address) {
// return 0xff;
case 0:
case ENABLE: { /* Read data register. */
case ENABLE: { /* Read data register. Zeroing afterwards is a guess. */
const auto result = data_register_;
if(data_register_ & 0x80) {
@ -96,36 +96,41 @@ uint8_t IWM::read(int address) {
//
// {CA1,CA0,SEL,CA2}
// case 0: // Head step direction.
// case 0: // Head step direction. (0 = inward)
// printf("head step direction)\n");
// break;
case SEL: // Disk in place.
// (0 = disk present)
LOG("disk in place)");
sense = drives_[active_drive_] && drives_[active_drive_]->has_disk() ? 0 : 1;
break;
// case CA0: // Disk head step completed (1 = still stepping?).
// case CA0: // Disk head step completed.
// (0 = still stepping)
// printf("head stepping)\n");
// break;
//
case CA0|SEL: // Disk locked (i.e. write-protect tab).
case CA0|SEL: // Disk locked.
// (0 = write protected)
LOG("disk locked)");
// sense = drives_[active_drive_] && drives_[active_drive_]->get_is_read_only() ? 0x00 : 0x80;
sense = drives_[active_drive_] && drives_[active_drive_]->get_is_read_only() ? 1 : 0;
sense = drives_[active_drive_] && drives_[active_drive_]->get_is_read_only() ? 0 : 1;
break;
case CA1: // Disk motor running.
// (0 = motor on)
LOG("disk motor running)");
sense = drives_[active_drive_] && drives_[active_drive_]->get_motor_on() ? 0 : 1;
break;
case CA1|SEL: // Head at track 0.
// (0 = at track 0)
LOG("head at track 0)");
sense = drives_[active_drive_] && drives_[active_drive_]->get_is_track_zero() ? 0 : 1;
break;
case CA1|CA0|SEL: // Tachometer (?)
case CA1|CA0|SEL: // Tachometer.
// (arbitrary)
sense = drives_[active_drive_] && drives_[active_drive_]->get_tachometer() ? 0 : 1;
LOG("tachometer " << PADHEX(2) << int(sense) << ")");
break;
@ -139,16 +144,19 @@ uint8_t IWM::read(int address) {
// break;
//
case CA2|CA1: // Single- or double-sided drive.
// (0 = single sided)
LOG("single- or double-sided drive)");
sense = drives_[active_drive_] && (drives_[active_drive_]->get_head_count() == 1) ? 1 : 0;
sense = drives_[active_drive_] && (drives_[active_drive_]->get_head_count() == 1) ? 0 : 1;
break;
case CA2|CA1|CA0: // Present/HD. (per the Mac Plus ROM)
case CA2|CA1|CA0: // "Present/HD" (per the Mac Plus ROM)
// (0 = ??HD??)
LOG("present/HD)");
sense = drives_[active_drive_] ? 0 : 1;
sense = drives_[active_drive_] ? 1 : 0;
break;
case CA2|CA1|CA0|SEL: // Drive installed. (per Inside Macintosh)
case CA2|CA1|CA0|SEL: // Drive installed.
// (0 = present, 1 = missing)
LOG("drive installed)");
sense = drives_[active_drive_] ? 0 : 1;
break;