make disk read pulse 500 ns (not 1 us) (fixes DOS 3.2); enhance stepper motor logging; minor refactor

src/diskcontroller.cpp

@@ -66,6 +66,12 @@ unsigned char DiskController::io(const unsigned short addr, const unsigned char
         this->write = on;
         break;
     }
+//    if (this->dataRegister == 0xD5u) {
+//        printf("\n");
+//    }
+//    if (this->dataRegister & 0x80u) {
+//        printf("%02X ", this->dataRegister);
+//    }
     return on ? d : this->dataRegister;
 }
 
@@ -85,6 +91,7 @@ void DiskController::tick() {
 
     // run two LSS cycles = 2MHz
     stepLss();
+    this->currentDrive->clearPulse();
     stepLss();
 }
 
@@ -93,9 +100,6 @@ void DiskController::rotateCurrentDisk() {
     if (4 <= this->t) { // 4us interval between bits
         this->currentDrive->rotateDiskOneBit(); // (will also generate a read-pulse when it reads a 1-bit)
         this->t = 0;
-    } else {
-        // clear the read pulse (to make it last only 1us)
-        this->currentDrive->clearPulse();
     }
 }
 
@@ -105,6 +109,7 @@ void DiskController::stepLss() {
     this->seq = cmd & 0xF0u;
 
     // LSS command functions (UA2, 9-15, Table 9.3)
+//    printf("%02x:", cmd);
     if (cmd & 8u) {
         switch (cmd & 3u) {
         case 3:
@@ -118,6 +123,9 @@ void DiskController::stepLss() {
         case 1:
             this->dataRegister <<= 1;
             this->dataRegister |= ((cmd & 4u) >> 2);
+//            printf(this->dataRegister & 0x80u ? "\x1b[30;42m" : "\x1b[30;43m");
+//            printf("%02X\x1b[0m ", this->dataRegister);
+//            if (this->dataRegister & 0x80u) printf("\n");
             // TODO how to handle writing?
             break;
         }

src/diskcontroller.h

@@ -63,15 +63,6 @@ private:
                 this->currentDrive->writeBit(on);
         }
 
-//	unsigned char get() const
-//	{
-//		if (!this->motorOn)
-//		{
-//			return 0xFF;
-//		}
-//		return this->currentDrive->get();
-//	}
-
 	Drive& getDrive(const unsigned char drive)
 	{
 		return (drive == 0) ? this->drive1 : this->drive2;

src/drive.h

@@ -63,7 +63,7 @@ public:
     void unloadDisk() {
         this->disk.unload();
     }
-    bool isLoaded() {
+    bool isLoaded() const {
         return this->disk.isLoaded();
     }
 
@@ -108,7 +108,7 @@ public:
         }
     }
 
-    bool readPulse() {
+    bool readPulse() const {
         return this->pulse;
     }
     void clearPulse() {

src/lss.cpp

@@ -58,7 +58,7 @@ static void setbth(std::uint8_t lssrom[], std::uint8_t x, std::uint8_t both) {
 //}
 
 LSS::LSS(bool use13SectorDos32LSS):
-    use13SectorDos32LSS(use13SectorDos32LSS) {
+    use13Sector(use13SectorDos32LSS) {
     /*
      * LSS P6 ROM is stored here with different addressing bits
      * than in the original hardware, just for ease of understanding.
@@ -175,7 +175,7 @@ LSS::LSS(bool use13SectorDos32LSS):
     setseq(lss13rom,0x23u,0x30u);
     setseq(lss13rom,0x33u,0xD0u);
 
-//    if (use13SectorDos32LSS) {
+//    if (use13Sector) {
 //        for (unsigned int seq = 0; seq < 0x100u; seq += 0x10u) {
 //            showua2seq(lss13rom,seq);
 //        }

src/lss.h

@@ -25,7 +25,7 @@
 class LSS
 {
 private:
-    bool use13SectorDos32LSS;
+    bool use13Sector;
     std::uint8_t lssrom[0x100];
     std::uint8_t lss13rom[0x100];
 
@@ -34,7 +34,7 @@ public:
     ~LSS();
 
     std::uint8_t read(const std::uint8_t addr) {
-        return use13SectorDos32LSS ? lss13rom[addr] : lssrom[addr];
+        return use13Sector ? lss13rom[addr] : lssrom[addr];
     }
 };
 

src/main.cpp

@@ -104,6 +104,8 @@ static int run(const std::string& config_file) {
 extern "C"
 #endif
 int main(int argc, char* argv[]) {
+    setbuf(stdout, NULL);
+
     if (argc > 2) {
 		throw std::runtime_error("usage: epple2 [config-file]" );
 	}

src/steppermotor.cpp

@@ -63,7 +63,7 @@ undefined
 #include <iostream>
 
 StepperMotor::StepperMotor():
-    quarterTrack(QTRACK_MAX >> 1), // start in the middle of the disk... just for fun
+    quarterTrack(QTRACKS >> 1), // start in the middle of the disk... just for fun
 // TODO if we want to be extremely accurate, we should save each arm's position on shutdown and restore on startup
 // (because in the real-life Apple ][, the arm stays in the same position when powered off).
 	pos(0),
@@ -83,6 +83,8 @@ void StepperMotor::setMagnet(const unsigned char magnet, const bool on) {
         this->mags &= ~mask;
     }
 
+//    const std::uint8_t oldQT = this->quarterTrack;
+
     const char newPos = mapMagPos[this->mags];
     char d = 0;
     if (newPos >= 0) {
@@ -92,31 +94,22 @@ void StepperMotor::setMagnet(const unsigned char magnet, const bool on) {
         this->quarterTrack += d;
         if (this->quarterTrack < 0)
             this->quarterTrack = 0;
-        else if (this->quarterTrack > QTRACK_MAX)
+        else if (QTRACKS <= this->quarterTrack)
-            this->quarterTrack = QTRACK_MAX;
+            this->quarterTrack = QTRACKS-1;
     }
-//    std::cout << " ARM: magnet " << (unsigned int)magnet << " " << (on ? "on " : "off" );
-//    std::cout << " [" <<
-//        ((mags&1)?"*":".") <<
-//        ((mags&2)?"*":".") <<
-//        ((mags&4)?"*":".") <<
-//        ((mags&8)?"*":".") <<
-//        "]";
-//    if (d != 0) {
-//        std::cout << " track " << std::hex << (unsigned int)(this->quarterTrack >> 2);
-//        int fract = this->quarterTrack & 3;
-//        if (fract != 0) {
-//            std::cout << (fract == 1 ? " +.25" : fract == 2 ? " +.5" : " +.75");
-//        }
-//    }
-//    std::cout << std::endl;
-}
-//static void dumpQTrack(std::uint8_t currentQuarterTrack) {
-//    if (currentQuarterTrack % 4) {
-//        const std::uint8_t hundredths((currentQuarterTrack%4) * 25);
-//        printf("track 0x%02X +.%02d\n", currentQuarterTrack/4, hundredths);
-//    } else {
-//        printf("track 0x%02X\n", currentQuarterTrack/4);
-//    }
-//}
 
+//    const std::uint8_t newQT = this->quarterTrack;
+//    const std::int8_t deltaQT = newQT - oldQT;
+
+//    printf("ARM: ph%d %s [%c%c%c%c] T$%02X.%02d %s %+0.2f\n",
+//       (std::uint8_t)magnet,
+//       on ? "+" : "-",
+//       (mags&1)?'*':'.',
+//       (mags&2)?'*':'.',
+//       (mags&4)?'*':'.',
+//       (mags&8)?'*':'.',
+//       this->quarterTrack / 4,
+//       (this->quarterTrack % 4) * 25,
+//       deltaQT>0 ? "-->" : deltaQT<0 ? "<--" : "   ",
+//       (deltaQT % 4) / 4.0);
+}

src/steppermotor.h

@@ -22,12 +22,11 @@
 
 class StepperMotor {
 private:
-    enum { TRACKS_PER_DISK = 0x23 };
+    enum { QTRACKS = 141 };
-    enum { QTRACK_MAX = TRACKS_PER_DISK << 2 };
 
     // quarter track: 0=t0, 1=t0.25, 2=t0.5, 3=t0.75, 4=t1, ... 140=t35.00
-    // (see TMAP in  WOZ file format)
+    // (see TMAP in WOZ file format spec)
-    signed short quarterTrack;
+    std::int16_t quarterTrack;
     signed char pos; // 0 - 7
     unsigned char mags;
 

src/wozfile.cpp

@@ -306,7 +306,7 @@ void WozFile::rotateOneBit(std::uint8_t currentQuarterTrack) {
         this->byt = 0;
         this->bit = 0x80u;
     }
-}
+ }
 
 
 
@@ -317,6 +317,7 @@ bool WozFile::getBit(std::uint8_t currentQuarterTrack) {
     }
 
     if (this->tmap[currentQuarterTrack] == 0xFFu) {
+//        printf("Reading from uninitialized track; will generate random data.\n");
         return false; // empty track
     }