brymen-dmm: unbreak temperature response parsing

[libsigrok.git] / src / hardware / brymen-dmm / parser.c

diff --git a/src/hardware/brymen-dmm/parser.c b/src/hardware/brymen-dmm/parser.c
index baab57d9dcf8f03598b0576ce2b3bf9ab741bb03..40ca6c86074084cd6bf320627e1e725c70c6bf15 100644 (file)
--- a/src/hardware/brymen-dmm/parser.c
+++ b/src/hardware/brymen-dmm/parser.c
@@ -195,24 +195,24 @@ static int parse_value(const char *txt, size_t len, float *floatval)
        return SR_OK;
 }
 
-static void parse_flags(const uint8_t *buf, struct brymen_flags *info)
+static void parse_flags(const uint8_t *bfunc, struct brymen_flags *info)
 {
-       info->is_low_batt       = (buf[4 + 3] & (1 << 7)) != 0;
-
-       info->is_decibel        = (buf[4 + 1] & (1 << 5)) != 0;
-       info->is_duty_cycle     = (buf[4 + 1] & (1 << 3)) != 0;
-       info->is_hertz          = (buf[4 + 1] & (1 << 2)) != 0;
-       info->is_amp            = (buf[4 + 1] & (1 << 1)) != 0;
-       info->is_beep           = (buf[4 + 1] & (1 << 0)) != 0;
-
-       info->is_ohm            = (buf[4 + 0] & (1 << 7)) != 0;
-       info->is_fahrenheit     = (buf[4 + 0] & (1 << 6)) != 0;
-       info->is_celsius        = (buf[4 + 0] & (1 << 5)) != 0;
-       info->is_diode          = (buf[4 + 0] & (1 << 4)) != 0;
-       info->is_capacitance    = (buf[4 + 0] & (1 << 3)) != 0;
-       info->is_volt           = (buf[4 + 0] & (1 << 2)) != 0;
-       info->is_dc             = (buf[4 + 0] & (1 << 1)) != 0;
-       info->is_ac             = (buf[4 + 0] & (1 << 0)) != 0;
+       info->is_low_batt       = (bfunc[3] & (1 << 7)) != 0;
+
+       info->is_decibel        = (bfunc[1] & (1 << 5)) != 0;
+       info->is_duty_cycle     = (bfunc[1] & (1 << 3)) != 0;
+       info->is_hertz          = (bfunc[1] & (1 << 2)) != 0;
+       info->is_amp            = (bfunc[1] & (1 << 1)) != 0;
+       info->is_beep           = (bfunc[1] & (1 << 0)) != 0;
+
+       info->is_ohm            = (bfunc[0] & (1 << 7)) != 0;
+       info->is_fahrenheit     = (bfunc[0] & (1 << 6)) != 0;
+       info->is_celsius        = (bfunc[0] & (1 << 5)) != 0;
+       info->is_diode          = (bfunc[0] & (1 << 4)) != 0;
+       info->is_capacitance    = (bfunc[0] & (1 << 3)) != 0;
+       info->is_volt           = (bfunc[0] & (1 << 2)) != 0;
+       info->is_dc             = (bfunc[0] & (1 << 1)) != 0;
+       info->is_ac             = (bfunc[0] & (1 << 0)) != 0;
 }
 
 SR_PRIV int brymen_parse(const uint8_t *buf, float *floatval,
@@ -221,26 +221,40 @@ SR_PRIV int brymen_parse(const uint8_t *buf, float *floatval,
        struct brymen_flags flags;
        struct brymen_header *hdr;
        uint8_t *bfunc;
-       int asciilen;
+       const char *txt;
+       int txtlen;
+       char *unit;
+       int ret;
 
        (void)info;
 
        hdr = (void *)buf;
        bfunc = (uint8_t *)(buf + sizeof(struct brymen_header));
-
-       analog->meaning->mqflags = 0;
-
-       /* Give some debug info about the package. */
-       asciilen = hdr->len - 4;
-       sr_dbg("DMM flags: %.2x %.2x %.2x %.2x",
-              bfunc[3], bfunc[2], bfunc[1], bfunc[0]);
-       /* Value is an ASCII string. */
-       sr_dbg("DMM packet: \"%.*s\"", asciilen, bfunc + 4);
-
-       parse_flags(buf, &flags);
-       if (parse_value((const char *)(bfunc + 4), asciilen, floatval) != SR_OK)
+       txt = (const char *)&bfunc[4];
+       txtlen = hdr->len - 4;
+       sr_dbg("DMM bfunc: %02x %02x %02x %02x, text '%.*s'",
+               bfunc[3], bfunc[2], bfunc[1], bfunc[0], txtlen, txt);
+
+       memset(&flags, 0, sizeof(flags));
+       parse_flags(bfunc, &flags);
+       if (flags.is_fahrenheit || flags.is_celsius) {
+               /*
+                * The value text in temperature mode includes the C/F
+                * suffix between the mantissa and the exponent, which
+                * breaks the text to number conversion. Example data:
+                * " 0.0217CE+3". Remove the C/F unit identifier.
+                */
+               unit = strchr(txt, flags.is_fahrenheit ? 'F' : 'C');
+               if (!unit)
+                       return SR_ERR;
+               *unit = ' ';
+       }
+       ret = parse_value(txt, txtlen, floatval);
+       sr_dbg("floatval: %f, ret %d", *floatval, ret);
+       if (ret != SR_OK)
                return SR_ERR;
 
+       analog->meaning->mqflags = 0;
        if (flags.is_volt) {
                analog->meaning->mq = SR_MQ_VOLTAGE;
                analog->meaning->unit = SR_UNIT_VOLT;