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r3264 Sunday 14th September, 2008 at 15:40:55 UTC by Wilbert Pol
[JUPITER] Added preliminary .TAP support (not working yet).
[src/mess]mess.mak
[src/mess/drivers]jupiter.c
[src/mess/formats]jupi_tap.c* jupi_tap.h*

src/mess/mess.mak
r3263r3264
932932$(MESSOBJ)/jupiter.a : \
933933   $(MESS_DRIVERS)/jupiter.o   \
934934   $(MESS_MACHINE)/jupiter.o   \
935   $(MESS_FORMATS)/jupi_tap.o
935936
936937$(MESSOBJ)/mbee.a :    \
937938   $(MESS_VIDEO)/mbee.o    \
src/mess/formats/jupi_tap.c
r0r3264
1/********************************************************************
2
3Support for Jupiter Ace .tap cassette images
4
5For more information see:
6- http://www.jupiter-ace.co.uk/faq_ace_tap_format.html
7- http://www.jupiter-ace.co.uk/doc_AceTapeFormat.html
8
9********************************************************************/
10#include "jupi_tap.h"
11
12
13#define SMPLO   -32768
14#define SILENCE   0
15#define SMPHI   32767
16
17
18static int cas_size;
19
20
21/*******************************************************************
22   Generate one high-low cycle of sample data
23********************************************************************/
24INLINE int jupiter_tap_cycle(INT16 *buffer, int sample_pos, int high, int low)
25{
26   int i = 0;
27
28   if ( buffer )
29   {
30      while( i < high)
31      {
32         buffer[ sample_pos + i ] = SMPHI;
33         i++;
34      }
35
36      while( i < high + low )
37      {
38         buffer[ sample_pos + i ] = SMPLO;
39         i++;
40      }
41   }
42   return high + low;
43}
44
45
46INLINE int jupiter_tap_silence(INT16 *buffer, int sample_pos, int samples)
47{
48   int i = 0;
49
50   if ( buffer )
51   {
52      while( i < samples )
53      {
54         buffer[ sample_pos + i ] = SILENCE;
55         i++;
56      }
57   }
58   return samples;
59}
60
61
62static int jupiter_handle_tap(INT16 *buffer, const UINT8 *casdata)
63{
64   int   data_pos, sample_count;
65
66   /* Make sure the file starts with a valid header */
67   if ( cas_size < 0x1C )
68      return -1;
69   if ( casdata[0] != 0x1A || casdata[1] != 0x00 )
70      return -1;
71
72   data_pos = 0;
73   sample_count = 0;
74
75   while( data_pos < cas_size )
76   {
77      UINT16   block_size;
78      int      i;
79
80      /* Handle a block of tape data */
81      block_size = casdata[data_pos] + ( casdata[data_pos + 1] << 8 );
82      data_pos += 2;
83     
84      /* Make sure there are enough bytes left */
85      if ( data_pos > cas_size )
86         return -1;
87
88      /* 2 seconds silence */
89      sample_count += jupiter_tap_silence( buffer, sample_count, 2 * 44100 );
90
91      /* Add pilot tone samples: 4096 for header, 512 for data */
92      for( i = ( block_size == 0x001A ) ? 4096 : 512; i; i-- )
93         sample_count += jupiter_tap_cycle( buffer, sample_count, 27, 27 );
94
95      /* Sync samples */
96      sample_count += jupiter_tap_cycle( buffer, sample_count, 8, 11 );
97
98      /* Data samples */
99      for ( ; block_size ; data_pos++, block_size-- )
100      {
101         UINT8   data = casdata[data_pos];
102
103         for ( i = 0; i < 8; i++ )
104         {
105            if ( data & 0x80 )
106               sample_count += jupiter_tap_cycle( buffer, sample_count, 21, 22 );
107            else
108               sample_count += jupiter_tap_cycle( buffer, sample_count, 10, 11 );
109
110            data <<= 1;
111         }
112      }
113
114      /* End mark samples */
115      sample_count += jupiter_tap_cycle( buffer, sample_count, 12, 57 );
116
117      /* 3 seconds silence */
118      sample_count += jupiter_tap_silence( buffer, sample_count, 3 * 44100 );
119   }
120   return sample_count;
121}
122
123
124/*******************************************************************
125   Generate samples for the tape image
126********************************************************************/
127static int jupiter_tap_fill_wave(INT16 *buffer, int sample_count, UINT8 *bytes)
128{
129   return jupiter_handle_tap( buffer, bytes );
130}
131
132
133/*******************************************************************
134   Calculate the number of samples needed for this tape image
135********************************************************************/
136static int jupiter_tap_to_wav_size(const UINT8 *casdata, int caslen)
137{
138   cas_size = caslen;
139
140   return jupiter_handle_tap( NULL, casdata );
141}
142
143
144static const struct CassetteLegacyWaveFiller jupiter_legacy_fill_wave =
145{
146   jupiter_tap_fill_wave,               /* fill_wave */
147   -1,                              /* chunk_size */
148   0,                              /* chunk_samples */
149   jupiter_tap_to_wav_size,            /* chunk_sample_calc */
150   44100,                           /* sample_frequency */
151   0,                              /* header_samples */
152   0                              /* trailer_samples */
153};
154
155
156static casserr_t jupiter_tap_identify(cassette_image *cassette, struct CassetteOptions *opts)
157{
158   return cassette_legacy_identify(cassette, opts, &jupiter_legacy_fill_wave);
159}
160
161
162static casserr_t jupiter_tap_load(cassette_image *cassette)
163{
164   return cassette_legacy_construct(cassette, &jupiter_legacy_fill_wave);
165}
166
167
168static const struct CassetteFormat jupiter_tap_format =
169{
170   "tap",
171   jupiter_tap_identify,
172   jupiter_tap_load,
173   NULL
174};
175
176
177CASSETTE_FORMATLIST_START(jupiter_cassette_formats)
178   CASSETTE_FORMAT(jupiter_tap_format)
179CASSETTE_FORMATLIST_END
src/mess/formats/jupi_tap.h
r0r3264
1/*********************************************************************
2
3    jupi_tap.h
4
5    Format code for Jupiter Ace casette files
6
7*********************************************************************/
8
9#ifndef JUPI_TAP_H
10#define JUPI_TAP_H
11
12#include "formats/cassimg.h"
13
14CASSETTE_FORMATLIST_EXTERN(jupiter_cassette_formats);
15
16#endif /* JUPI_TAP_H */
17
src/mess/drivers/jupiter.c
r3263r3264
3232#include "devices/cartslot.h"
3333#include "devices/cassette.h"
3434#include "sound/speaker.h"
35#include "formats/jupi_tap.h"
3536
37
3638/* This needs to be moved to drivers/xtal */
3739#define XTAL_6_5MHz   6500000
3840
r3263r3264
289291   return 0;
290292}
291293
294
295static cassette_config jupiter_cassette_config =
296{
297   jupiter_cassette_formats,
298   NULL,
299   CASSETTE_STOPPED
300};
301
292302/* machine definition */
293303static MACHINE_DRIVER_START( jupiter )
294304   /* basic machine hardware */
r3263r3264
316326   MDRV_SOUND_ADD("speaker", SPEAKER, 0)
317327   MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 1.00)
318328
319   MDRV_CASSETTE_ADD( "cassette", default_cassette_config )
329   MDRV_CASSETTE_ADD( "cassette", jupiter_cassette_config )
320330MACHINE_DRIVER_END
321331
322332

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