Measurement system

Page last updated 06 Jan 2011, by Claes Ekengren. 0 replies average, INIFILE, logger, Temperature, uLCD-32PT(SGC)

Make a param.ini file that looks like this !

Store it on local file system.

I use ch- 1,2,3,4 for voltage 0-3.3volt, and ch- 5,6 for temperature (LM335).

LM335 is pulled up to +5V with 1k.

USB-stick is connected to D-, D+, +5v, GND.

Measurement_system

LOG.CSV will be written to USB-stick during logging, and file name will be stepped each time logging is started (log1.csv, log2.csv, log3.csv)

After mbed-reset it will start with LOG.CSV again (or filename specified in param.ini) .

(CSV files can be opened with excel, where graphs/calculations can be made).

Connect push button on p12 with 5k pull up resistor, It's used for stopping ongoing log session.

For best result - connect low pass filters on all six adc inputs (1k/0.1uF).

To see a little bit what is happening.....Connect with Tera Term at 115200 baud ( VT100, Local echo on, New line receive LF ).

If you experience that logging hangs after START button has been pressed, remove and insert USB-stick / reset mbed, and try to start again.

It seems like +5V to USB-stick needs to be toggled after bootup in some cases.

Do not remove USB-stick during logging, file must be closed first, wait until session is finished, or stop it with stop button before remove of USB-stick.

Enjoy !!!

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