doc: Add paragraph noting differences in JST polarity

[fw/altos] / doc / altusmetrum.xsl

diff --git a/doc/altusmetrum.xsl b/doc/altusmetrum.xsl
index b2677a029ed9c66f3c33b3861fddb0382ece3ee0..aa218c5cc598fffa26f33479ecc2cc8d2816a4d6 100644 (file)
--- a/doc/altusmetrum.xsl
+++ b/doc/altusmetrum.xsl
@@ -277,6 +277,17 @@ NAR #88757, TRA #12200
       apogee and main ejection charges.  All Altus Metrum products are 
       designed for use with single-cell batteries with 3.7 volts nominal.
     </para>
+    <para>
+      The battery connectors are a standard 2-pin JST connector and
+      match batteries sold by Spark Fun. Other vendors sell similar
+      batteries for RC aircraft using mating connectors, however the
+      polarity for those is generally reversed from the batteries used
+      by Altus Metrum products. In particular, the Tenergy batteries
+      supplied for use in Featherweight flight computers are not
+      compatible with Altus Metrum flight computers or battery
+      chargers. <emphasis>Check polarity before connecting any battery
+      not purchased from Altus Metrum or Spark Fun.</emphasis>
+    </para>
     <para>
       By default, we use the unregulated output of the Li-Po battery directly
       to fire ejection charges.  This works marvelously with standard
@@ -2199,7 +2210,7 @@ NAR #88757, TRA #12200
        </listitem>
        <listitem>
          <para>
-           RF interface for battery charging, configuration, and data recovery.
+           RF interface for configuration, and data recovery.
          </para>
        </listitem>
        <listitem>