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This is nice information.<br>
<br>
I looked at it a bit and one thing that jumped out and swatted me on
the nose is the fact that the radio board 3.3v power supply current
draw can greatly exceed the current an FTDI chip can put out. The
"usual" FTDI chips (and it appears Sparkfun is using a vanilla
FT232RL) can only source about 50ma at 3.3 volts from their internal
regulators. The ESP8266 board has typical (i.e. possibly far from
"worst case") current requirements looking like this (from the table
on the web site linked to below):<br>
<br>
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802.11b, CCK 1Mbps, POUT=+19.5dBm 215mA<br>
802.11b, CCK 11Mbps, POUT=+18.5dBm197mA<br>
802.11g, OFDM 54Mbps, POUT=+16dBm145mA<br>
802.11n, MCS7, POUT =+14dBm135mA<br>
802.11b, packet size of 1024 bytes, -80dBm60mA<br>
802.11b, packet size of 1024 bytes, -70dBm60mA<br>
802.11b, packet size of 1024 bytes, -65dBm62mA<br>
Standby0.9uA<br>
Deep sleep10mA<br>
Saving mode DTIM 1 1.2mA<br>
Saving mode DTIM 3 0.86mA<br>
Shutdown0.5uA<br class="Apple-interchange-newline">
<br>
So a lot of the time you're basically trying to kill the FTDI chip.
I personally let the smoke out of one of these by accidentally
telling it to try to supply a motor controller (off by an inch with
the wire in the breadboard and hit the wrong power rail). They will
die if tortured enough.<br>
<br>
So plan on the FTDI's 5v line driving an outboard 3.3v regulator
with proper capacitors on both sides. An oscilloscope could confirm
the radio is getting a proper supply and that it's not being yanked
down by sudden changes in current demand.<br>
<br>
-Pete<br>
<br>
<br>
<div class="moz-cite-prefix">On 05/19/2015 11:00 AM, Christian
Lilley via TriEmbed wrote:<br>
</div>
<blockquote
cite="mid:CANXjGa+fPpN9zb87drD0LdUNQv36DJTC4aqPMT97LtGJL+xstA@mail.gmail.com"
type="cite">
<div dir="ltr">All of the information on the ESP8266 can be <a
moz-do-not-send="true" href="https://nurdspace.nl/ESP8266">found
here.</a>
<div><br>
</div>
<div>According to the wiki the baud rate should be <span
style="color:rgb(0,0,0);font-family:Verdana,Arial,'Trebuchet
MS';font-size:12.3199996948242px;line-height:18.4799995422363px">57600.
Sparkfun does mention that a level shifter should be used
and that it should not be connected directly to 5V sources. </span></div>
<div><span
style="color:rgb(0,0,0);font-family:Verdana,Arial,'Trebuchet
MS';font-size:12.3199996948242px;line-height:18.4799995422363px"><br>
</span></div>
<div><font color="#000000" face="Verdana, Arial, Trebuchet MS"><span
style="font-size:12.3199996948242px;line-height:18.4799995422363px"><a
moz-do-not-send="true"
href="http://allaboutee.com/2014/12/27/esp8266-arduino-code-and-circuit/">Here
is an example </a>using the Arduino's software serial
to communicate with the ESP and the normal serial lines to
communicate with the FTDI board. This guy uses a 9600 baud
rate but I don't know if that is a custom setting he uses.</span></font></div>
</div>
<div class="gmail_extra"><br clear="all">
<div>
<div class="gmail_signature">
<div dir="ltr">
<div style="font-family:arial,helvetica,sans-serif"><font
style="font-family:arial,sans-serif" color="#444444">Christian
Lilley | Electrical Engineer</font><br
style="font-family:arial,sans-serif">
<div style="font-family:arial,sans-serif">
<div>
<div dir="ltr">
<p style="margin:0in 0in
0.0001pt;font-family:Calibri,sans-serif;font-size:11pt"><b><i><span
style="font-size:8pt"> </span></i></b><span
style="font-size:11pt;color:windowtext"><a
moz-do-not-send="true"
href="http://www.gomohu.com/"
style="color:blue;font-size:11pt"
target="_blank"><img
src="cid:part3.07050405.00090900@soper.us"
alt="images" type="image/png" border="0"
height="32" width="200"></a></span></p>
<p style="margin:0in 0in
0.0001pt;font-family:Calibri,sans-serif;font-size:11pt"><span
style="color:rgb(68,68,68)"><a
moz-do-not-send="true" value="+19198801283"
style="color:rgb(17,85,204)">919.794.8627
ext 129</a></span></p>
<p style="margin:0in 0in
0.0001pt;font-family:Calibri,sans-serif;font-size:11pt"><span
style="color:rgb(68,68,68)"><span
style="color:rgb(255,255,0)"><a
moz-do-not-send="true"
href="mailto:christian.lilley@gomohu.com"
style="color:rgb(17,85,204)"
target="_blank">christian.lilley@gomohu.com</a></span></span><span
style="color:rgb(255,255,0)"><span
style="font-size:13px;font-family:Verdana,sans-serif"></span></span></p>
<span style="color:rgb(255,255,0)"></span></div>
</div>
<span style="color:rgb(255,255,0)"><br>
</span></div>
<div style="font-family:arial,sans-serif"><span
style="color:rgb(255,255,0)"><a
moz-do-not-send="true"
href="http://www.gomohu.com/"
style="color:rgb(17,85,204)" target="_blank">www.gomohu.com</a></span></div>
</div>
<div style="font-family:arial,helvetica,sans-serif"><font><br>
</font></div>
</div>
</div>
</div>
<br>
<div class="gmail_quote">On Tue, May 19, 2015 at 10:44 AM,
Nathan Yinger via TriEmbed <span dir="ltr"><<a
moz-do-not-send="true" href="mailto:triembed@triembed.org"
target="_blank">triembed@triembed.org</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>
<div>
<div>
<div>
<div>So, I have an ESP8266, a new serial adapter (<a
moz-do-not-send="true"
href="https://www.sparkfun.com/products/9873"
target="_blank">https://www.sparkfun.com/products/9873</a>),
and I'm trying to get them to communicate.<br>
<br>
</div>
When I power up the ESP8266, it creates a wifi
network where I can join and ping it, but as far
as I can tell, reprogramming it requires a serial
connection.<br>
<br>
</div>
When the ESP8266 is powered on, the 'tx' light on
the serial adapter flashes continuously, which I
assume means the ESP8266 is transmitting something.
Nothing appears in my serial monitor though, not
even gibberish.<br>
<br>
I'm using the serial monitor that comes with the
Arduino IDE, with various baud rates and line
endings. I haven't found any documentation about the
byte length, parity, or character encoding used by
ESP8266. I get a TTYUSB device in /dev when I plug
in the serial adapter, so it appears to be doing
something.<br>
<br>
</div>
Does anyone know what's required to make the chips do
something? Or have a working setup they could bring to
the next meeting?<br>
<br>
</div>
Thanks,<br>
</div>
~Nathan<br>
</div>
<br>
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<br>
</blockquote>
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<pre wrap="">_______________________________________________
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