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Diffstat (limited to 'trunk/src/lib/formats/p6001_cas.c')
-rw-r--r--trunk/src/lib/formats/p6001_cas.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/trunk/src/lib/formats/p6001_cas.c b/trunk/src/lib/formats/p6001_cas.c
new file mode 100644
index 00000000000..ca3e0d4cd43
--- /dev/null
+++ b/trunk/src/lib/formats/p6001_cas.c
@@ -0,0 +1,93 @@
+/*
+ * Nec PC-6001 cassette format handling
+ */
+
+#include "p6001_cas.h"
+
+#define WAVE_HIGH 0x5a9e
+#define WAVE_LOW -0x5a9e
+
+static int cas_size;
+
+static int pc6001_fill_wave(INT16* buffer, UINT8 data, int sample_pos)
+{
+ int x;
+ int sample_count = 0;
+
+ // one byte = 8 samples
+ for(x=0;x<8;x++)
+ {
+ if(buffer)
+ buffer[sample_pos+x] = ((data >> (7-x)) & 1) ? WAVE_HIGH : WAVE_LOW;
+ }
+
+ sample_count+=8;
+ return sample_count;
+}
+
+static int pc6001_handle_cas(INT16* buffer, const UINT8* casdata)
+{
+ int sample_count = 0;
+ int data_pos = 0;
+
+ while(sample_count < cas_size)
+ {
+ sample_count += pc6001_fill_wave(buffer,casdata[data_pos],sample_count);
+ data_pos++;
+ }
+
+ return sample_count;
+}
+
+/*******************************************************************
+ Calculate the number of samples needed for this tape image
+********************************************************************/
+static int pc6001_cas_to_wav_size (const UINT8 *casdata, int caslen)
+{
+ cas_size = caslen*8;
+
+ return pc6001_handle_cas(NULL,casdata);
+}
+
+/*******************************************************************
+ Generate samples for the tape image
+********************************************************************/
+static int pc6001_cas_fill_wave(INT16 *buffer, int sample_count, UINT8 *bytes)
+{
+ return pc6001_handle_cas(buffer,bytes);
+}
+
+static const struct CassetteLegacyWaveFiller pc6001_legacy_fill_wave =
+{
+ pc6001_cas_fill_wave, /* fill_wave */
+ -1, /* chunk_size */
+ 0, /* chunk_samples */
+ pc6001_cas_to_wav_size, /* chunk_sample_calc */
+ 8000, /* sample_frequency */
+ 0, /* header_samples */
+ 0 /* trailer_samples */
+};
+
+static casserr_t pc6001_cas_identify(cassette_image *cassette, struct CassetteOptions *opts)
+{
+ return cassette_legacy_identify(cassette, opts, &pc6001_legacy_fill_wave);
+}
+
+
+
+static casserr_t pc6001_cas_load(cassette_image *cassette)
+{
+ return cassette_legacy_construct(cassette, &pc6001_legacy_fill_wave);
+}
+
+
+static const struct CassetteFormat pc6001_cassette_format = {
+ "cas",
+ pc6001_cas_identify,
+ pc6001_cas_load,
+ NULL
+};
+
+CASSETTE_FORMATLIST_START(pc6001_cassette_formats)
+ CASSETTE_FORMAT(pc6001_cassette_format)
+CASSETTE_FORMATLIST_END