<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[Yet more SPI woes (MRF24J40MA)]]></title><description><![CDATA[<p dir="auto">Hello.</p>
<p dir="auto">I am trying to communicate to a Zigbee antenna, model as in subject.<br />
Today I tried various settings with no avail; I have prepared my Omega2 BASE to get gcc tomorrow so I might try more accurate tests.</p>
<p dir="auto">Various threads involving SPI issues I've seen:</p>
<ul>
<li><a href="https://community.onion.io/topic/2345/omega2-spi-first-bit-missing-wrong" rel="nofollow">https://community.onion.io/topic/2345/omega2-spi-first-bit-missing-wrong</a></li>
<li><a href="https://community.onion.io/topic/2344/omega2-spi-problem" rel="nofollow">https://community.onion.io/topic/2344/omega2-spi-problem</a></li>
<li><a href="https://community.onion.io/topic/2027/help-about-spi-of-omega2" rel="nofollow">https://community.onion.io/topic/2027/help-about-spi-of-omega2</a></li>
</ul>
<p dir="auto">For the time being, I am attempting a <em>short read</em> as at <a href="http://ww1.microchip.com/downloads/en/DeviceDoc/39776C.pdf" rel="nofollow">page 14</a>. This seems coherent with what <code>spi-tool ... read</code> &lt;--&gt; <code>spiTransfer</code> would be able to do.</p>
<p dir="auto">I tried</p>
<pre><code>spi-tool -b 1 -d 32766 read 0x00
</code></pre>
<p dir="auto">Expected: 0x00. Got: 0x00. So far so good?<br />
Unfortunately, I always get only 0, for everything I read, for example:</p>
<pre><code>spi-tool -b 1 -d 32766 read 0x2C
</code></pre>
<p dir="auto">Expected: read of register 0x16 (PACON0) value at POR 00101001 = 0x29<br />
Get: 0x00</p>
<p dir="auto">I figured maybe my pins were wrong or perhaps frequency too high. So I tried</p>
<pre><code>spi-tool -b 1 -d 32766 --frequency 50000 --bpw 8 --sck 7 --mosi 8 --miso 9 --cs 6 setup
</code></pre>
<p dir="auto">Attempted other reads; this device has few non-zero fields but with no luck. I always get 0.</p>
<p dir="auto">I need help troubleshooting this, because I have checked the connections 42 times and I'm now out of ideas. I only have a $10 multimeter. BTW, will spi-tool or the library (they are sorta equivalent from what I see) support 12-bit values? If the command-response model has to be honored, I need 12-bit values to perform <em>long reads</em> on this device.</p>
]]></description><link>http://community.onion.io/topic/2362/yet-more-spi-woes-mrf24j40ma</link><generator>RSS for Node</generator><lastBuildDate>Wed, 09 Sep 2026 16:49:01 GMT</lastBuildDate><atom:link href="http://community.onion.io/topic/2362.rss" rel="self" type="application/rss+xml"/><pubDate>Thu, 14 Sep 2017 18:47:59 GMT</pubDate><ttl>60</ttl><item><title><![CDATA[Reply to Yet more SPI woes (MRF24J40MA) on Thu, 14 Sep 2017 18:47:59 GMT]]></title><description><![CDATA[<p dir="auto">Hello.</p>
<p dir="auto">I am trying to communicate to a Zigbee antenna, model as in subject.<br />
Today I tried various settings with no avail; I have prepared my Omega2 BASE to get gcc tomorrow so I might try more accurate tests.</p>
<p dir="auto">Various threads involving SPI issues I've seen:</p>
<ul>
<li><a href="https://community.onion.io/topic/2345/omega2-spi-first-bit-missing-wrong" rel="nofollow">https://community.onion.io/topic/2345/omega2-spi-first-bit-missing-wrong</a></li>
<li><a href="https://community.onion.io/topic/2344/omega2-spi-problem" rel="nofollow">https://community.onion.io/topic/2344/omega2-spi-problem</a></li>
<li><a href="https://community.onion.io/topic/2027/help-about-spi-of-omega2" rel="nofollow">https://community.onion.io/topic/2027/help-about-spi-of-omega2</a></li>
</ul>
<p dir="auto">For the time being, I am attempting a <em>short read</em> as at <a href="http://ww1.microchip.com/downloads/en/DeviceDoc/39776C.pdf" rel="nofollow">page 14</a>. This seems coherent with what <code>spi-tool ... read</code> &lt;--&gt; <code>spiTransfer</code> would be able to do.</p>
<p dir="auto">I tried</p>
<pre><code>spi-tool -b 1 -d 32766 read 0x00
</code></pre>
<p dir="auto">Expected: 0x00. Got: 0x00. So far so good?<br />
Unfortunately, I always get only 0, for everything I read, for example:</p>
<pre><code>spi-tool -b 1 -d 32766 read 0x2C
</code></pre>
<p dir="auto">Expected: read of register 0x16 (PACON0) value at POR 00101001 = 0x29<br />
Get: 0x00</p>
<p dir="auto">I figured maybe my pins were wrong or perhaps frequency too high. So I tried</p>
<pre><code>spi-tool -b 1 -d 32766 --frequency 50000 --bpw 8 --sck 7 --mosi 8 --miso 9 --cs 6 setup
</code></pre>
<p dir="auto">Attempted other reads; this device has few non-zero fields but with no luck. I always get 0.</p>
<p dir="auto">I need help troubleshooting this, because I have checked the connections 42 times and I'm now out of ideas. I only have a $10 multimeter. BTW, will spi-tool or the library (they are sorta equivalent from what I see) support 12-bit values? If the command-response model has to be honored, I need 12-bit values to perform <em>long reads</em> on this device.</p>
]]></description><link>http://community.onion.io/post/14501</link><guid isPermaLink="true">http://community.onion.io/post/14501</guid><dc:creator><![CDATA[Massimo Del Zotto]]></dc:creator><pubDate>Thu, 14 Sep 2017 18:47:59 GMT</pubDate></item><item><title><![CDATA[Reply to Yet more SPI woes (MRF24J40MA) on Thu, 14 Sep 2017 19:56:49 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="http://community.onion.io/uid/4548">@Massimo-Del-Zotto</a> Getting nothing back often means you haven't activated the chip select that is connected to the peripheral.</p>
<p dir="auto">A scope is really key to debugging this, or one of the cheap USB-based logic analyzers.</p>
]]></description><link>http://community.onion.io/post/14502</link><guid isPermaLink="true">http://community.onion.io/post/14502</guid><dc:creator><![CDATA[Chris Stratton]]></dc:creator><pubDate>Thu, 14 Sep 2017 19:56:49 GMT</pubDate></item><item><title><![CDATA[Reply to Yet more SPI woes (MRF24J40MA) on Fri, 15 Sep 2017 08:38:45 GMT]]></title><description><![CDATA[<p dir="auto">Sounds legit.<br />
So in the meanwhile I hooked up another RF device and re-soldered and re-checked everything again.</p>
<p dir="auto">Nothing seemed to work either; next week I'll hook it up at a scope at office.</p>
]]></description><link>http://community.onion.io/post/14505</link><guid isPermaLink="true">http://community.onion.io/post/14505</guid><dc:creator><![CDATA[Massimo Del Zotto]]></dc:creator><pubDate>Fri, 15 Sep 2017 08:38:45 GMT</pubDate></item></channel></rss>