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-rw-r--r--firmware/src/picc/decoder.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/firmware/src/picc/decoder.c b/firmware/src/picc/decoder.c
new file mode 100644
index 0000000..9f9191a
--- /dev/null
+++ b/firmware/src/picc/decoder.c
@@ -0,0 +1,65 @@
+/* Decoder Core for OpenPCD / OpenPICC
+ * (C) 2006 by Harald Welte <hwelte@hmw-consulting.de>
+ */
+
+#include <errno.h>
+#include <sys/types.h>
+#include <picc/decoder.h>
+
+#include <os/dbgu.h>
+
+static struct decoder_algo *decoder_algo[DECODER_NUM_ALGOS];
+
+static int get_next_data(struct decoder_state *st, u_int8_t *data)
+{
+ u_int8_t parity_sample;
+ u_int32_t bytesample;
+
+ bytesample = st->algo->get_next_bytesample(st, &parity_sample);
+
+ return st->algo->decode_sample(bytesample, data);
+}
+
+/* iterate over sample buffer (size N bytes) and decode data */
+int decoder_decode(u_int8_t algo, const char *sample_buf,
+ int sample_buf_size, char *data_buf)
+{
+ int i, ret;
+ struct decoder_state st;
+
+ if (algo >= DECODER_NUM_ALGOS)
+ return -EINVAL;
+
+ st.buf = sample_buf;
+ st.buf32 = (u_int32_t *) st.buf;
+ st.bit_ofs = 0;
+ st.algo = decoder_algo[algo];
+
+ for (i = 0; i < (sample_buf_size*8)/st.algo->bits_per_sampled_char;
+ i++) {
+ ret = get_next_data(&st, &data_buf[i]);
+ if (ret < 0) {
+ DEBUGPCR("decoder error %d at data byte %u",
+ ret, i);
+ return ret;
+ }
+ }
+
+ return i+1;
+}
+
+int decoder_register(int algnum, struct decoder_algo *algo)
+{
+ if (algnum >= DECODER_NUM_ALGOS)
+ return -EINVAL;
+
+ decoder_algo[algnum] = algo;
+
+ return 0;
+}
+
+void decoder_init(void)
+{
+ decoder_register(DECODER_MILLER, &miller_decoder);
+ decoder_register(DECODER_NRZL, &nrzl_decoder);
+}
personal git repositories of Harald Welte. Your mileage may vary