From: Frank Mori Hess <fmhess@speakeasy.net>
Date: Fri, 29 Nov 2002 22:02:35 +0000 (+0000)
Subject: added some comments about how internal voltage reference appears when
X-Git-Tag: r0_7_21~278
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=48b8faab177763f99d3769fc37df72258a23e0cd;p=comedilib.git

added some comments about how internal voltage reference appears when
using +-50V or +-20V input ranges
---

diff --git a/comedi_calibrate/ni.c b/comedi_calibrate/ni.c
index 695ea0a..0f40057 100644
--- a/comedi_calibrate/ni.c
+++ b/comedi_calibrate/ni.c
@@ -313,12 +313,13 @@ void ni_setup_observables( calibration_setup_t *setup )
 	}
 }
 
+/* XXX for +-50V and +-20V ranges, the reference source goes 0V
+ * to 50V instead of 0V to 5V */
 static unsigned int cal_gain_register_bits_611x( double *voltage )
 {
 	unsigned int bits;
 
 	bits = 200.0 * ( *voltage / 5.0 );
-	if( bits < 1 ) bits = 1;
 	if( bits > 200 ) bits = 200;
 
 	*voltage = 5.0 * ( bits / 200.0 );