Skip to content

Q
qgroundcontrol
Switch branch/tag
Find file
Normal viewHistoryPermalink
xbee_getanalog.3.html 3.32 KB
Newer Older
Franz's avatar
added libxbee library
258ce38a
 
Franz committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 
<HTML><HEAD><TITLE>Manpage of XBEE_GETPACKET</TITLE>
</HEAD><BODY>
<H1>XBEE_GETPACKET</H1>
Section: Linux Programmer's Manual (3)<BR>Updated: 2009-11-01<BR><A HREF="#index">Index</A>
<A HREF="../index.html">Return to Main Contents</A><HR>

<A NAME="lbAB">&nbsp;</A>
<H2>NAME</H2>

xbee_hasanalog, xbee_getanalog
<A NAME="lbAC">&nbsp;</A>
<H2>SYNOPSIS</H2>

<B>#include &lt;<A HREF="file:/usr/include/xbee.h">xbee.h</A>&gt;</B>

<P>
<B>int xbee_hasanalog(xbee_pkt *</B><I>pkt</I><B>,int </B><I>sample</I><B>, int </B><I>input</I><B>);</B>

<P>
<B>double xbee_getanalog(xbee_pkt *</B><I>pkt</I><B>,int </B><I>sample</I><B>, int </B><I>input</I><B>, double </B><I>Vref</I><B>);</B>


<A NAME="lbAD">&nbsp;</A>
<H2>DESCRIPTION</H2>

The
<B>xbee_hasanalog</B>()

function will check the packet for the presence of an analog sample on the specified input.
<P>
The
<B>xbee_getanalog</B>()

function will read the packet and return the sample value for the specified analog input.
<P>
They both take 3 arguments, with the same purposes.
<P>
The argument
<I>pkt</I>

points to a packet that was previously retrieved with 
<B>xbee_getpacket</B>()

<P>
The argument
<I>sample</I>

selects the sample within the packet to use.
<P>
The argument
<I>input</I>

specifies which input you are interested in testing.
<P>
<B>xbee_getanalog</B>()

also takes a fourth argument that allows you to provide a
<I>Vref</I>

value. This allows the function to convert the raw ADC value into a voltage for you.
<A NAME="lbAE">&nbsp;</A>
<H2>RETURN VALUE</H2>

The
<B>xbee_hasanalog</B>()

function will return
<B>1</B>

if the provided packet has sample data for the specified input, otherwise
<B>0</B>.

<P>
The
<B>xbee_getanalog</B>()

function will return the raw ADC value (0 - 1023) if the provided packet has sample data for the specified input and Vref was given as zero.
If Vref was non-zero, then the return value will be the voltage read.
A
<B>-1</B>

will be returned if the packet does not contain sample data.
<P>
<A NAME="lbAF">&nbsp;</A>
<H2>EXAMPLE</H2>

To read sample data from previously made connection:

<PRE>
#include &lt;<A HREF="file:/usr/include/xbee.h">xbee.h</A>&gt;
xbee_pkt *pkt;
double Vref = 3.3;
if ((pkt = xbee_getpacket(con)) != NULL) {
  if (xbee_hasanalog(pkt,0,0)) {
    printf(&quot;A0 read %fv,xbee_getanalog(pkt,0,0,Vref));
  } else {
    printf(&quot;No A0 data);
  }
  free(pkt);
}
</PRE>


<A NAME="lbAG">&nbsp;</A>
<H2>AUTHOR</H2>

Attie Grande &lt;<A HREF="mailto:attie@attie.co.uk">attie@attie.co.uk</A>&gt; 
<A NAME="lbAH">&nbsp;</A>
<H2>SEE ALSO</H2>

<B><A HREF="../man3/libxbee.3.html">libxbee</A></B>(3),

<B><A HREF="../man3/xbee_pkt.3.html">xbee_pkt</A></B>(3),

<B><A HREF="../man3/xbee_getpacket.3.html">xbee_getpacket</A></B>(3),

<B><A HREF="../man3/xbee_hasdigital.3.html">xbee_hasdigital</A></B>(3),

<B><A HREF="../man3/xbee_getdigital.3.html">xbee_getdigital</A></B>(3)

<P>

<HR>
<A NAME="index">&nbsp;</A><H2>Index</H2>
<DL>
<DT><A HREF="#lbAB">NAME</A><DD>
<DT><A HREF="#lbAC">SYNOPSIS</A><DD>
<DT><A HREF="#lbAD">DESCRIPTION</A><DD>
<DT><A HREF="#lbAE">RETURN VALUE</A><DD>
<DT><A HREF="#lbAF">EXAMPLE</A><DD>
<DT><A HREF="#lbAG">AUTHOR</A><DD>
<DT><A HREF="#lbAH">SEE ALSO</A><DD>
</DL>
<HR>
This document was created by
<A HREF="http://localhost/cgi-bin/man/man2html">man2html</A>,
using the manual pages.<BR>
Time: 00:08:23 GMT, March 30, 2011
</BODY>
</HTML>