de NØBEL, Kevin

I received a cheap PC based logic analyzer that I wanted to try out.  It has an analog channel too.  Along with my mod to an FTDI board for getting more 3.3v power thru it, I had incorporated a 1ohm resistor in line so I could measure current draw.   

 

This is the result of my first use of the analog part of the analyzer.  Its an analysis of the current draw over time of my UdpTemp project https://github.com/n0bel/esp8266-UdpTemp The top trace in grey shows the output of the serial port, to help me coordinate the different stages of the sequence.  The bottom trace in blue is the current draw.  The chart inverted because the resistor i'm measuring is on the positive rail.   The software that came with the analyzer is very lacking in the analog portion of its functions.  So I had to take a screen capture and then add my own annotations.  I think its an interesting graph.   The sample rate was 12 MHz (because I can't seem to find how to slow it down in the software), so it captures very fast changes in current flow.  

During the "Wait for DS18B20 temperature cvt", the system is idle (os_timer).  I see it shut down a bit during that time, running at about 40ma.  I look forward to doing more of these analyses playing with different wifi sleep modes.   I'm sure they will look just as interesting.