LeoEc Hardware Design Files in EAGLE. Not much to say, there are some custom parts will add Library after I clean it up!
- Charge Pump section
- Analog Front End - Wein oscillator, eC probe as one part of gain.
- AC output rectification for input into uC
- uC controller subsection
- reverse voltage protection
- USB and BNC on same side to allow punch out on Front Panels
- Wein Osc should be at least 1kHz, preferable with AGC but this design seems stable at most common temp range
- Leonardo Digital Header (Pin matching)
- Leonardo Analog Header (Pin matching)
- add ACG?
- Silkscreen is small and hard to read in some portions
- ESD protection on USB is on the TODO list
- Auto selectable voltage similar to Arduino boards (USB, while 3.3v powered)
- Take a look in LeoEc's Firmware Repo For Arduino!
- Check out my I2C eC interfaceMiniEc for a really cost effective PH Probe interface!
With Arduino1.0.2 and up how the Leonardo is reset was changed and with the popularity of the LeoEc platform I though it would be a good idea to update the hardware and bring the bootloader up to the newest version.
As before reading eC has never been easier, and with the new hardware version so it augmenting LeoEc! All Standard Leonardo pins are brought out via the Digital Header and Analog header!
Simply plug in LeoEc via a USB port, point you favorite Serial Port monitor to LeoEc's port and off you go! LeoEc even works on openWRT flashed routers for eC readings over Wifi!
Please see LeoEc's Project page for more information! http://www.sparkyswidgets.com/portfolio-item/LeoEc/ Basic Usage
Usage of LeoEc is very easy, with on board USB a fully CDC compatible bootloader (modified leonardo) all you need to do is plug it in and send some serial commands! Send an S to calibrate to eC 1 solution, F to calibrate to 2 an R to read and etc...
There are 2 serial ports one for the USB and one is the hardware serial port(Tx,Rx), this makes it useful as a USB to serial converter as well, but also means that the proper port must be select for use in any project. For example a Raspberry pie could interface LeoEc(careful on levels) over USB serial while the same data is dumped over the Hardware Serial to another Arduino. An I2C slave example code is also implemented which uses some of the same commands and shows how to easily implement a eC sensor with an I2C interface!
####Some of the commands are:
- C : Continuous Read Mode: Dump readings and data every second
- R : Single eC reading: response "eC: XX.XX" where XX.XX is the eC
- E : Exit continuous read mode
- S : set eC1 Calibration point
- F : set eC2 Calibration point: also relalcs probe slope and saves settings to EEPROM
- T : set eC3 Calibration point: also recalcs probe slope and saves settings to EEPROM
- X : restore settings to default and ideal probe conditions
LeoEc by Ryan Edwards, Sparky's Widgets is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
Based on a work at http://www.sparkyswidgets.com/portfolio-item/LeoEc/
