- fps set to 15

- First effort for the track preloading
- Disk accelerator back to 25 MHz

A2Mac/ViewController.swift

@@ -265,7 +265,7 @@ class ViewController: NSViewController {
 //        return
         
         frameCnt += 1
-        if ( frameCnt == 15 ) {
+        if ( frameCnt == fps / 2 ) {
 //            flashingSpace = blockChar
             ViewController.charConvTbl = ViewController.charConvTblFlashOn
         }

A2Mac/src/cpu/6502.h

@@ -101,7 +101,7 @@ extern void hires_Update(void);
 extern double mips;
 extern double mhz;
 
-#define fps 30
+#define fps 15
 
 extern void tst6502(void);
 extern void m6502_ColdReset(void);

A2Mac/src/cpu/instructions/6502_instr_call_ret_jump.h

@@ -68,7 +68,7 @@ INLINE void RTS() {
 
     // disk accelerator would only work for a certain amount of time
     // currently it is 200ms simulated times
-    if ( m6502.clktime - disk.clk_since_last_read > clk_diskAcceleratorTimeout ) {
+    if ( m6502.clktime - disk.clk_last_access > clk_diskAcceleratorTimeout ) {
         clk_6502_per_frm = clk_6502_per_frm_set;
     }
 }

A2Mac/src/dev/disk/disk.c

@@ -17,7 +17,7 @@ disk_t disk = {
     0,              // clk_since_last_read
 };
 
-const unsigned long long clk_6502_per_frm_diskAccelerator = 100 * M / fps; // disk acceleration bumps up CPU clock to 100 MHz
+const unsigned long long clk_6502_per_frm_diskAccelerator = 25 * M / fps; // disk acceleration bumps up CPU clock to 25 MHz
 const unsigned long long clk_diskAcceleratorTimeout = 200000ULL;
 
 
@@ -60,7 +60,7 @@ void disk_phase() {
         
 //        printf(", p:%d d:%d l:%d: ph:%u trk:%u)", position, direction, lastPosition, phase.count, woz_tmap.phase[phase.count]);
                 
-        disk.clk_since_last_read = m6502.clktime;
+        disk.clk_last_access = m6502.clktime;
         clk_6502_per_frm = clk_6502_per_frm_diskAccelerator;
 
     }
@@ -74,8 +74,9 @@ void disk_phase() {
 
 uint8_t disk_read() {
     dbgPrintf("io_DISK_READ (S%u)\n", 6);
-    disk.clk_since_last_read = m6502.clktime;
+    disk.clk_last_access = m6502.clktime;
     clk_6502_per_frm = clk_6502_per_frm_diskAccelerator;
+    
     return woz_read();
 }
 

A2Mac/src/dev/disk/disk.h

@@ -18,17 +18,21 @@
 #define minDiskPhaseNum      0
 #define maxDiskPhaseNum     (minDiskPhaseStates * maxDiskTrackNum)
 
+
 typedef struct phase_s {
     uint8_t lastMagnet  : 4;
     uint8_t magnet      : 4;
     int     count;
 } phase_t;
 
+
 typedef struct disk_s {
     phase_t phase;
-    uint64_t clk_since_last_read;
+    uint64_t clk_last_access;
+    uint64_t clk_last_read;
 } disk_t;
 
+
 extern disk_t disk;
 
 

A2Mac/src/dev/disk/woz.c

@@ -26,6 +26,54 @@ woz_header_t woz_header;
 woz_chunk_header_t woz_chunk_header;
 woz_tmap_t woz_tmap;
 woz_trks_t woz_trks;
+int track_loaded = -1;
+
+
+
+#pragma pack(push, 1)
+
+typedef union trackEntry_u {
+    struct {
+        uint8_t data;
+        uint8_t shift;
+    };
+    uint16_t shift16;
+} trackEntry_t;
+
+#pragma pack(pop)
+
+trackEntry_t prepared_track[WOZ_TRACK_BYTE_COUNT];
+
+typedef enum readState_e {
+    readNormal = 0,
+    readHold,
+} readState_t;
+
+readState_t readState = readNormal;
+uint8_t readLatch;
+
+
+void woz_loadTrack( int track ) {
+    trackEntry_t reg = {0};
+
+    reg.shift = woz_trks[track].data[0];
+    reg.data =  woz_trks[track].data[1];
+    prepared_track[0] = reg;
+
+    for ( int offs = 1; offs < WOZ_TRACK_BYTE_COUNT; offs++ ) {
+        
+        for ( int i = 0; i < 8; i++ ) {
+            if (reg.shift & 0x80) {
+                reg.shift = 0;
+            }
+            
+            reg.shift16 <<= 1;
+        }
+        
+        reg.data = woz_trks[track].data[ (offs + 1) % WOZ_TRACK_BYTE_COUNT ];
+        prepared_track[offs] = reg;
+    }
+}
 
 
 uint8_t woz_read() {
@@ -36,6 +84,11 @@ uint8_t woz_read() {
         dbgPrintf("TRCK TOO HIGH!\n");
         return rand();
     }
+    
+    if ( track != track_loaded ) {
+        woz_loadTrack(track);
+        track_loaded = track;
+    }
 
 #ifdef WOZ_REAL_SPIN
     
@@ -166,39 +219,35 @@ uint8_t woz_read() {
 
     
 #elif defined( WOZ_REAL_SPIN2 )
-    clkelpased = m6502.clktime - clklast;
-    clklast = m6502.clktime & ~3;
+//    clkelpased = m6502.clktime - disk.clk_last_read;
+//    disk.clk_last_read = m6502.clktime;
 
-    bitOffset = (clkelpased >> 2) & 7;
-    trackOffset += (clkelpased >> 5) % WOZ_TRACK_BYTE_COUNT;
-    WOZread.data = woz_trks[track].data[trackOffset];
+    bitOffset = (m6502.clktime >> 2) & 7;
+    trackOffset = (m6502.clktime >> 5) % WOZ_TRACK_BYTE_COUNT;
+    trackEntry_t reg = prepared_track[trackOffset];
+    
+    do {
+        switch (readState) {
+            case readNormal:
+                readLatch = reg.shift;
+                break;
+                
+            case readHold:
+            default:
+                readState = readNormal;
+                break;
+        }
 
-    // to avoid infinite loop and to search for bit 7 high
-    for ( int i = 0; i < WOZ_TRACK_BYTE_COUNT * 8; i++ ) {
-        if ( ++bitOffset >= 8 ) {
-            bitOffset = 0;
-//                    if ( ++trackOffset >= WOZ_TRACK_BYTE_COUNT ) {
-//                        trackOffset = 0;
-//                    }
-            trackOffset++;
-            trackOffset %= WOZ_TRACK_BYTE_COUNT;
-
-//                    printf("offs:%u\n", trackOffset);
-            WOZread.data = woz_trks[track].data[trackOffset];
+        if (reg.shift & 0x80) {
+            reg.shift = 0;
+            readState = readHold;
         }
         
-        WOZread.shift16 <<= 1;
-        if ( WOZread.valid ) {
-            uint8_t byte = WOZread.shift;
-//                    printf("%02X ", byte);
-            WOZread.shift = 0;
-            if (outdev) fprintf(outdev, "byte: %02X\n", byte);
-            return byte;
-        }
-    }
-    if (outdev) fprintf(outdev, "TIME OUT!\n");
-    return rand();
-    
+        reg.shift16 <<= 1;
+    } while ( --bitOffset > 0 );
+
+    printf("READ: clk:%llu  to:%u  bo:%llu  B:%02X\n", m6502.clktime, trackOffset, (m6502.clktime >> 2) & 7, readLatch);
+    return readLatch;
 
     
 #else // WOZ_REAL_SPIN

A2Mac/src/dev/disk/woz.h

@@ -76,6 +76,7 @@ typedef woz_track_t woz_trks_t[DISKII_MAXTRACKS];
 
 
 #define __NO__WOZ_REAL_SPIN2
+
 #ifdef WOZ_REAL_SPIN
 
 typedef union {
@@ -118,7 +119,7 @@ extern uint8_t   WOZlatch;
 //extern woz_trks_t woz_trks;
 
 
-extern uint8_t woz_read();
+extern uint8_t woz_read(void);
 extern void woz_loadFile( const char * filename );