X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=output%2Foutput_vcd.c;h=d8ce6ef063e9ad53eb068916d8505c9d5f8d0705;hb=c4fffe1e9606e3e63a4cd0b760a37beb1f122cc5;hp=1acf4a7b10fa70cce67673e73e0b3f8348630769;hpb=5cca9adbf27252349729cdb1e1c6ca0a526561b1;p=libsigrok.git

diff --git a/output/output_vcd.c b/output/output_vcd.c
index 1acf4a7b..d8ce6ef0 100644
--- a/output/output_vcd.c
+++ b/output/output_vcd.c
@@ -158,6 +158,7 @@ static int data(struct output *o, char *data_in, uint64_t length_in,
 	unsigned int i, outsize;
 	int p, curbit, prevbit;
 	uint64_t sample, prevsample;
+	static uint64_t samplecount = 0;
 	char *outbuf, *c;
 
 	ctx = o->internal;
@@ -180,26 +181,25 @@ static int data(struct output *o, char *data_in, uint64_t length_in,
 	/* TODO: Are disabled probes handled correctly? */
 
 	for (i = 0; i <= length_in - ctx->unitsize; i += ctx->unitsize) {
+		samplecount++;
 		memcpy(&sample, data_in + i, ctx->unitsize);
+		if (i == 0)
+			prevsample = sample;
+		else
+			memcpy(&prevsample, data_in + i - 1, ctx->unitsize);
+
 		for (p = 0; p < ctx->num_enabled_probes; p++) {
-			curbit = (sample & ((uint64_t) (1 << p))) != 0;
-			if (i == 0) {
-				prevbit = ~curbit;
-			} else {
-				memcpy(&prevsample, data_in + i - 1,
-				       ctx->unitsize);
-				prevbit =
-				    (prevsample & ((uint64_t) (1 << p))) != 0;
-			}
-
-			/* VCD only contains deltas/changes. */
+			curbit = (sample & ((uint64_t) (1 << p))) >> p;
+			prevbit = (prevsample & ((uint64_t) (1 << p))) >> p;
+
+			/* VCD only contains deltas/changes of signals. */
 			if (prevbit == curbit)
 				continue;
 
-			/* FIXME: Only once per sample? */
-			/* TODO: Is 'i' correct here? */
+			/* Output which signal changed to which value. */
 			c = outbuf + strlen(outbuf);
-			sprintf(c, "#%i\n%i%c\n", i, curbit, (char)('!' + p));
+			sprintf(c, "#%" PRIu64 "\n%i%c\n", samplecount,
+				curbit, (char)('!' + p));
 		}
 
 		/* TODO: Use realloc() if strlen(outbuf) is almost "full"... */