* UNI-T UT372 protocol parser.
*/
+#include <stdlib.h>
+#include <stdint.h>
+#include <math.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#define LOG_PREFIX "ut372"
+static const uint8_t lookup[] = {
+ 0x7B,
+ 0x60,
+ 0x5E,
+ 0x7C,
+ 0x65,
+ 0x3D,
+ 0x3F,
+ 0x70,
+ 0x7F,
+ 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 FALSE;
+ 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, value, divisor;
+ uint8_t segments, flags1, flags2;
+
+ (void) info;
+
+ flags1 = decode_pair(buf + 21);
+ flags2 = decode_pair(buf + 23);
+
+ if (flags2 & FLAGS2_RPM_MASK) {
+ analog->mq = SR_MQ_FREQUENCY;
+ analog->unit = SR_UNIT_REVOLUTIONS_PER_MINUTE;
+ } else if (flags2 & FLAGS2_COUNT_MASK) {
+ analog->mq = SR_MQ_COUNT;
+ analog->unit = SR_UNIT_UNITLESS;
+ }
+
+ if (flags1 & FLAGS1_HOLD_MASK)
+ analog->mqflags |= SR_MQFLAG_HOLD;
+ if (flags2 & FLAGS2_MIN_MASK)
+ analog->mqflags |= SR_MQFLAG_MIN;
+ if (flags2 & FLAGS2_MAX_MASK)
+ analog->mqflags |= SR_MQFLAG_MAX;
+ if (flags2 & FLAGS2_AVG_MASK)
+ analog->mqflags |= SR_MQFLAG_AVG;
+
+ value = 0;
+ divisor = 1;
+
+ for (i = 0; i < 5; i++) {
+ 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);
+ break;
+ }
+ }
+ if (segments & DECIMAL_POINT_MASK)
+ divisor = pow(10, i);
+ }
+
+ *floatval = (float) value / divisor;
+
return SR_OK;
}