From: Alexandru Gagniuc <redacted>
Date: Mon, 4 Apr 2016 01:04:42 +0000 (-0700)
Subject: analog: Add MQ Flag for four-wire measurements
X-Git-Tag: libsigrok-0.5.0~493
X-Git-Url: http://sigrok.org/gitweb/?a=commitdiff_plain;h=6d5cd3bd383b293f16d4db0c91c366d939e4851b;p=libsigrok.git

analog: Add MQ Flag for four-wire measurements

On the high-end bench multimeters, resistance can be measured with a
kelvin connection as well as the more common two wire method. Provide
a flag which can indicate if four-wire mode is used.
---

diff --git a/include/libsigrok/libsigrok.h b/include/libsigrok/libsigrok.h
index 31ee5dce..6096b5bf 100644
--- a/include/libsigrok/libsigrok.h
+++ b/include/libsigrok/libsigrok.h
@@ -383,6 +383,8 @@ enum sr_mqflag {
 	SR_MQFLAG_REFERENCE = 0x80000,
 	/** Unstable value (hasn't settled yet). */
 	SR_MQFLAG_UNSTABLE = 0x100000,
+	/** Measurement is four wire (e.g. Kelvin connection). */
+	SR_MQFLAG_FOUR_WIRE = 0x200000,
 
 	/*
 	 * Update mq_strings[] (analog.c) and fancyprint() (output/analog.c)
diff --git a/src/analog.c b/src/analog.c
index 892cc6ec..da1560cd 100644
--- a/src/analog.c
+++ b/src/analog.c
@@ -114,6 +114,7 @@ static struct unit_mq_string mq_strings[] = {
 	{ SR_MQFLAG_AVG, " AVG" },
 	{ SR_MQFLAG_REFERENCE, " REF" },
 	{ SR_MQFLAG_UNSTABLE, " UNSTABLE" },
+	{ SR_MQFLAG_FOUR_WIRE, " 4-WIRE" },
 	ALL_ZERO
 };
 
diff --git a/src/output/analog.c b/src/output/analog.c
index 5e6e4aca..72d1eb87 100644
--- a/src/output/analog.c
+++ b/src/output/analog.c
@@ -273,6 +273,8 @@ static void fancyprint(int unit, int mqflags, float value, GString *out)
 		g_string_append_printf(out, " REF");
 	if (mqflags & SR_MQFLAG_UNSTABLE)
 		g_string_append_printf(out, " UNSTABLE");
+	if (mqflags & SR_MQFLAG_FOUR_WIRE)
+		g_string_append_printf(out, " 4-WIRE");
 	g_string_append_c(out, '\n');
 }