added basic support for the loop flags in tzx [David Haywood]

hash/spectrum_cass.xml

@@ -19,7 +19,7 @@
      The MESS emulation at the time of writing isn't very good, the following emulators are used to determine how things should work
      
       Fuse (Free Unix Spectrum Emulator) - Free, High Compatibility can run some of the trickier images, Windows port available - http://fuse-emulator.sourceforge.net/
-      Spectaculator                      - Commercial, a bit more user friendly than above, similar compatibility               - http://www.spectaculator.com/
+      Spectaculator                      - Commercial, a bit more user friendly than above, similar compatibility               - http://www.spectaculator.com/     
      
      Note, even with those emulators you'll have to turn off some of the speed cheats on loading to get good compatibilty for example, in Fuse
       Use Tape Traps
@@ -30,9 +30,14 @@
      MESS doesn't have any accelerated loading so some games which require the tricks to be disabled in other emulators work in MESS without trickery, eg Xanthius
      
      http://newton.sunderland.ac.uk/~specfreak/Schemes/schemes.html is a rather outdated guide mentioning some of the custom loaders, and showing disassemblies of them.
+  
+     legacy emulators including Real Spectrum ( http://zxm.speccy.cz/realspec/ ) appear to struggle with some of the more complex tape protections
+
+ 
+     ToDo: Find an emulator which works with the 'Gremlin 2' protected tapes 'M.A.S.K' and 'Basil The Great Mouse Detective' all TZX images I've found fail in the
+     above emulators, although RealSpectrum does load some copies of MASK but fails loading the 2nd part of the game.
      
 
-     legacy emulators including Real Spectrum ( http://zxm.speccy.cz/realspec/ ) appear to struggle with some of the more complex tape protections
 
 -->
 
@@ -344,8 +349,8 @@
 		</part>
 	</software>
 
-	<!-- loader fails before title screen, works in other emus -->
+	<!-- OK -->
-	<software name="batmana" cloneof="batman" supported="no">
+	<software name="batmana" cloneof="batman" >
 		<description>Batman (set 2)</description>
 		<year>1986</year>
 		<publisher>Ocean</publisher>
@@ -356,8 +361,9 @@
 		</part>
 	</software>
 
-	<!-- loader fails, doesn't boot after countdown completes, works in other emus -->
+	<!-- OK -->
-	<software name="batmanb" cloneof="batman" supported="no">
+  <!-- has load timer -->
+	<software name="batmanb" cloneof="batman" >
 		<description>Batman (set 3)</description>
 		<year>1986</year>
 		<publisher>Ocean</publisher>
@@ -368,7 +374,7 @@
 		</part>
 	</software>
 
-	<!-- loader fails after first block is loaded, suspect image, doesn't even run in 'realspectrum' -->
+	<!-- Unsupported block type (0x19 - Generalized Data Block) encountered -->
 	<software name="batmanc" cloneof="batman" supported ="no">
 		<description>Batman (set 4)</description>
 		<year>1986</year>
@@ -381,6 +387,7 @@
 	</software>
 
 	<!-- OK -->
+  <!-- colourful loader -->
 	<software name="batmand" cloneof="batman">
 		<description>Batman (set 5)</description>
 		<year>1986</year>
@@ -392,8 +399,8 @@
 		</part>
 	</software>
 
-	<!-- loader fails after first block is loaded, works in other emus -->
+	<!-- OK -->
-	<software name="batmane" cloneof="batman" supported="no">
+	<software name="batmane" cloneof="batman">
 		<description>Batman (set 6)</description>
 		<year>1986</year>
 		<publisher>Ocean</publisher>
@@ -404,8 +411,8 @@
 		</part>
 	</software>
 
-	<!-- loader fails before title screen -->
+	<!-- OK -->
-	<software name="batmanf" cloneof="batman" supported="no">
+	<software name="batmanf" cloneof="batman">
 		<description>Batman (set 7)</description>
 		<year>1986</year>
 		<publisher>Ocean</publisher>
@@ -416,8 +423,8 @@
 		</part>
 	</software>
 
-	<!-- MESS doesn't see full length of tape?, suspect image-->
+	<!-- Unsupported block type (0x19 - Generalized Data Block) encountered -->
-	<software name="batmang" cloneof="batman">
+	<software name="batmang" cloneof="batman" supported="no">
 		<description>Batman (set 8)</description>
 		<year>1986</year>
 		<publisher>Ocean</publisher>

src/lib/formats/tzx_cas.c

@@ -80,7 +80,7 @@ static void tzx_cas_get_blocks( const UINT8 *casdata, int caslen )
 {
 	int pos = sizeof(TZX_HEADER) + 2;
 	int max_block_count = INITIAL_MAX_BLOCK_COUNT;
-
+	int loopcount = 0, loopoffset = 0;
 	blocks = (UINT8**)malloc(max_block_count * sizeof(UINT8*));
 	memset(blocks,0,max_block_count);
 	block_count = 0;
@@ -134,15 +134,31 @@ static void tzx_cas_get_blocks( const UINT8 *casdata, int caslen )
 			datasize = casdata[pos] + (casdata[pos + 1] << 8) + (casdata[pos + 2] << 16);
 			pos += 3 + datasize;
 			break;
-		case 0x20: case 0x23: case 0x24:
+		case 0x20: case 0x23:
 			pos += 2;
 			break;
+
+		case 0x24:
+			loopcount = casdata[pos] + (casdata[pos + 1] << 8);
+			pos +=2;
+			loopoffset = pos;
+			break;
+
 		case 0x21: case 0x30:
 			datasize = casdata[pos];
 			pos += 1 + datasize;
 			break;
-		case 0x22: case 0x25: case 0x27:
+		case 0x22: case 0x27:
 			break;
+
+		case 0x25:
+			if (loopcount>0)
+			{
+				pos = loopoffset;
+				loopcount--;
+			}
+			break;
+
 		case 0x26:
 			datasize = casdata[pos] + (casdata[pos + 1] << 8);
 			pos += 2 + 2 * datasize;
@@ -313,6 +329,8 @@ static int tzx_cas_do_work( INT16 **buffer )
 
 	wave_data = WAVE_LOW;
 
+	int loopcount = 0, loopoffset = 0;
+
 	while (current_block < block_count)
 	{
 		int	pause_time;
@@ -322,8 +340,9 @@ static int tzx_cas_do_work( INT16 **buffer )
 		UINT8 *cur_block = blocks[current_block];
 		UINT8 block_type = cur_block[0];
 
+
 	/* Uncomment this to include into error.log a list of the types each block */
-//      LOG_FORMATS("tzx_cas_fill_wave: block %d, block_type %02x\n", current_block, block_type);
+	LOG_FORMATS("tzx_cas_fill_wave: block %d, block_type %02x\n", current_block, block_type);
 
 		switch (block_type)
 		{
@@ -460,14 +479,29 @@ static int tzx_cas_do_work( INT16 **buffer )
 			LOG_FORMATS("Please use a .tzx handling utility to split the merged tape files.\n");
 			current_block++;
 			break;
-		case 0x15:	/* Direct Recording */
+		case 0x24:	/* Loop Start */
-		case 0x18:	/* CSW Recording */
+			loopcount = cur_block[1] + (cur_block[2] << 8);
-		case 0x19:	/* Generalized Data Block */
+			current_block++;
+			loopoffset = current_block;
+
+			LOG_FORMATS("loop start %d %d\n",  loopcount, current_block);
+			break;
+		case 0x25:	/* Loop End */
+			if (loopcount>0)
+			{
+				current_block = loopoffset;
+				loopcount--;
+				LOG_FORMATS("do loop\n");
+			}
+			else
+			{
+				current_block++;
+			}			
+			break;
+
 		case 0x21:	/* Group Start */
 		case 0x22:	/* Group End */
 		case 0x23:	/* Jump To Block */
-		case 0x24:	/* Loop Start */
-		case 0x25:	/* Loop End */
 		case 0x26:	/* Call Sequence */
 		case 0x27:	/* Return From Sequence */
 		case 0x28:	/* Select Block */
@@ -477,6 +511,25 @@ static int tzx_cas_do_work( INT16 **buffer )
 			LOG_FORMATS("Unsupported block type (%02x) encountered.\n", block_type);
 			current_block++;
 			break;
+
+		case 0x15:	/* Direct Recording */
+			// having this missing is fatal
+			printf("Unsupported block type (0x15 - Direct Recording) encountered.\n");
+			current_block++;
+			break;
+
+		case 0x18:	/* CSW Recording */
+			// having this missing is fatal
+			printf("Unsupported block type (0x15 - CSW Recording) encountered.\n");
+			current_block++;
+			break;
+
+		case 0x19:	/* Generalized Data Block */
+			// having this missing is fatal
+			printf("Unsupported block type (0x19 - Generalized Data Block) encountered.\n");
+			current_block++;
+			break;
+
 		}
 	}
 	return size;