X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fdmm%2Fut372.c;h=271d034c3bbc3c3de899d23dace1b0fa5131f707;hb=2ea1fdf12113311cbe1a4316e9e2efe4d8ac40f0;hp=b5e2c703f7682eaf132888aa4fb70362951d089f;hpb=472bef399078cd7e80f35940a527828a1c841c46;p=libsigrok.git

diff --git a/src/dmm/ut372.c b/src/dmm/ut372.c
index b5e2c703..271d034c 100644
--- a/src/dmm/ut372.c
+++ b/src/dmm/ut372.c
@@ -14,22 +14,23 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 /*
  * UNI-T UT372 protocol parser.
  */
 
+#include <config.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <math.h>
-#include "libsigrok.h"
+#include <libsigrok/libsigrok.h>
 #include "libsigrok-internal.h"
 
 #define LOG_PREFIX "ut372"
 
-char lookup[] = {
+static const uint8_t lookup[] = {
 	0x7B,
 	0x60,
 	0x5E,
@@ -39,35 +40,86 @@ char lookup[] = {
 	0x3F,
 	0x70,
 	0x7F,
-	0x7D
+	0x7D,
 };
 
 #define DECIMAL_POINT_MASK 0x80
 
+#define FLAGS1_HOLD_MASK (1 << 2)
+
+#define FLAGS2_RPM_MASK (1 << 0)
+#define FLAGS2_COUNT_MASK (1 << 1)
+#define FLAGS2_MAX_MASK (1 << 4)
+#define FLAGS2_MIN_MASK (1 << 5)
+#define FLAGS2_AVG_MASK (1 << 6)
+
+/* Decode a pair of characters into a byte. */
+static uint8_t decode_pair(const uint8_t *buf)
+{
+	unsigned int i;
+	char hex[3];
+
+	hex[2] = '\0';
+
+	for (i = 0; i < 2; i++) {
+		hex[i] = buf[i];
+		if (hex[i] > 0x39)
+			hex[i] += 7;
+	}
+
+	return strtol(hex, NULL, 16);
+}
+
 SR_PRIV gboolean sr_ut372_packet_valid(const uint8_t *buf)
 {
-	return (buf[25] == '\r' && buf[26] == '\n');
+	uint8_t flags2;
+
+	if (!(buf[25] == '\r' && buf[26] == '\n'))
+		return FALSE;
+
+	flags2 = decode_pair(buf + 23);
+
+	if (!(flags2 & (FLAGS2_RPM_MASK | FLAGS2_COUNT_MASK)))
+		/* Device is in the setup menu - no valid data shown. */
+		return FALSE;
+
+	return TRUE;
 }
 
 SR_PRIV int sr_ut372_parse(const uint8_t *buf, float *floatval,
 		struct sr_datafeed_analog *analog, void *info)
 {
-	unsigned int i, j, segments, value, divisor;
-	char hex[3];
+	unsigned int i, j, value;
+	uint8_t segments, flags1, flags2;
+	int exponent;
 
 	(void) info;
 
-	hex[2] = '\0';
+	flags1 = decode_pair(buf + 21);
+	flags2 = decode_pair(buf + 23);
+
+	if (flags2 & FLAGS2_RPM_MASK) {
+		analog->meaning->mq = SR_MQ_FREQUENCY;
+		analog->meaning->unit = SR_UNIT_REVOLUTIONS_PER_MINUTE;
+	} else if (flags2 & FLAGS2_COUNT_MASK) {
+		analog->meaning->mq = SR_MQ_COUNT;
+		analog->meaning->unit = SR_UNIT_UNITLESS;
+	}
+
+	if (flags1 & FLAGS1_HOLD_MASK)
+		analog->meaning->mqflags |= SR_MQFLAG_HOLD;
+	if (flags2 & FLAGS2_MIN_MASK)
+		analog->meaning->mqflags |= SR_MQFLAG_MIN;
+	if (flags2 & FLAGS2_MAX_MASK)
+		analog->meaning->mqflags |= SR_MQFLAG_MAX;
+	if (flags2 & FLAGS2_AVG_MASK)
+		analog->meaning->mqflags |= SR_MQFLAG_AVG;
+
 	value = 0;
-	divisor = 1;
+	exponent = 0;
 
 	for (i = 0; i < 5; i++) {
-		for (j = 0; j < 2; j++) {
-			hex[j] = buf[2*i + 1 + j];
-			if (hex[j] > 0x39)
-				hex[j] += 7;
-		}
-		segments = strtol(hex, NULL, 16);
+		segments = decode_pair(buf + 1 + (2 * i));
 		for (j = 0; j < ARRAY_SIZE(lookup); j++) {
 			if (lookup[j] == (segments & ~DECIMAL_POINT_MASK)) {
 				value += j * pow(10, i);
@@ -75,13 +127,13 @@ SR_PRIV int sr_ut372_parse(const uint8_t *buf, float *floatval,
 			}
 		}
 		if (segments & DECIMAL_POINT_MASK)
-			divisor = pow(10, i);
+			exponent = -i;
 	}
 
-	*floatval = (float) value / divisor;
+	*floatval = (float) value * powf(10, exponent);
 
-	analog->mq = SR_MQ_FREQUENCY;
-	analog->unit = SR_UNIT_REVOLUTIONS_PER_MINUTE;
+	analog->encoding->digits  = -exponent;
+	analog->spec->spec_digits = -exponent;
 
 	return SR_OK;
 }