tag:blogger.com,1999:blog-10337211544985185422024-03-05T19:08:18.054-03:00pH meter using the Arduino boardCarloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.comBlogger16125tag:blogger.com,1999:blog-1033721154498518542.post-63162899513007246542012-11-18T02:16:00.001-02:002012-11-28T18:05:05.902-02:00Dettol plunger pump testHi again,
I made a test using the Dettol plunger pump to deliver water to a becker. Using a balance, I determined the volume delivered. You can see the unmount process from my last post Dettol No Touch Tearsdown.
To control it, I cut the infrared led and I connected the anode of the LED to the emitter of a BC548 transistor and the cathode of the LED to the ground. The transistor was pulled-up Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com5tag:blogger.com,1999:blog-1033721154498518542.post-88990513219537278942012-11-18T00:27:00.003-02:002012-11-18T01:18:18.881-02:00Dettol No Touch TearsdownHi.
I have been thinking to mount an automatic titrator. The most important parts are the liquid pump and the flow meter. I wanted something cheap and easy to buy. But, it is not a easy task.
Once, I was in a cosmetics shop, not for me, and I saw a Dettol No Touch Hand Wash System for R$ 27,40, here in Brazil. I bought one to umount and remove the liquid pump.
Photos
I took some photos the Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com2tag:blogger.com,1999:blog-1033721154498518542.post-86626353836776218322012-07-13T16:26:00.001-03:002012-07-13T16:26:07.193-03:00Controlling the pHduino with a Python-Jabberbot scriptIntroduction
This is a simple suggestion to control the pHduino over Internet using the Python-Jabberbot framework. It could be interesting, for example, if you want to monitor the pH of an aquarium from your work or using your smartphone from anywhere.
Of course you can change the python jabberbot script to control other devices over USB-Serial and an IM connection. It works well for Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com2tag:blogger.com,1999:blog-1033721154498518542.post-37252451666668027052012-03-12T16:13:00.000-03:002012-03-12T16:13:49.741-03:00pHduino Arduino 1.0 compatibleHi Folks,
I updated the code of the pHduino to be compatible with the Arudino 1.0. This is the changelog.
v041_20120312Removed all WProgram.h and WConstants.h and replaced by Arduino.h.
DS1307.cpp: Included Arduino.h.
DS1307.cpp: Typecast: from Wire.write(0x00) to Wire.write((uint8_t)0x00).
DS1307.h and twi_eeprom.h: Changed all Wire.send to Wire.write and all Wire.receive to Wire.read.
Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com0tag:blogger.com,1999:blog-1033721154498518542.post-68790654937021438232011-01-01T20:48:00.000-02:002011-01-01T20:48:08.821-02:00pHduino Datalogger shield releasedFeliz Ano Novo!
De pHduino Datalogger
At the begin of the 2010, I developed a datalogger shield for the pHduino. Again, I decided to make something simple to mount, modify, and use. I put the project in stand by because I need improve the code. Yesterday, I resolved make the modifications and I released it today. You can download the hardware and firmware files from the page of the project.
Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com8tag:blogger.com,1999:blog-1033721154498518542.post-66914835260883478512010-09-07T21:17:00.000-03:002010-09-07T21:17:14.513-03:00pHduino gerber filesOlá.
I have received some e-mails about people interested to buy a pHduino shield. But, I can't sell it, yet. The reason is I used the Eagle Free version (I can't make money with this version). Another reason is the business tax is very hard here in Brazil. Therefore, it is better you make your our PCB shield. I will resolve this problem in the next version.
Today, it is easy to make a PCB at Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com10tag:blogger.com,1999:blog-1033721154498518542.post-60433636725196880532010-04-25T22:41:00.003-03:002010-04-25T22:46:27.858-03:00pYpHpoT Python Script v0.1 releasedOlá.
This post is about first release of the pYpHpoT python script. It is a simple python script that reads the data from the pHduino and plots and saves the data to a text file.
The Graphical User Interface (GUI)
Up to now, the data from the pHduino were presented in the serial terminal. A good serial terminal has an option to save the data to a text file. But, they can not plot them. So, I Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com2tag:blogger.com,1999:blog-1033721154498518542.post-50891753692496406732010-04-21T13:07:00.001-03:002010-04-25T22:44:54.713-03:00pHduino Firmware v041 releasedHi everybody.
It is a newest release of the pHduino firmware with some little modifications. The most import addition is a magic number to simplify the pHduino operation.
Changelog v04_20100421
Removed duplicated unsigned word from readADC function.
Added magic number for check empty memory or different data block.
Clean up of version strings.
Magic Number
Let's suppose you just mounted a newCarloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com2tag:blogger.com,1999:blog-1033721154498518542.post-53566683444338907922010-02-17T13:59:00.001-02:002010-02-18T12:44:40.355-02:00How to sold a high impedance terminalThis post describes how to sold a high impedance terminal for a potentiometric measurement.
The problem
pH measurement, using glass electrode, is a technique which we read an electric potential difference without consume electric current. In fact, it is impossible not consume current. Every measurement system consumes some electric current. In this case, we need select an operational amplifier Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com2tag:blogger.com,1999:blog-1033721154498518542.post-58895821285852549282009-09-20T20:35:00.001-03:002009-09-24T13:31:39.111-03:00pHduino Firmware v04 releasedAgain, one more pHduino firmware release. Two main features: pH alarm, to warn when the pH is out of the normal range, and save parameters in the Arduino EEPROM memory, to recover the last configuration after a reset or a power off.
Changelog v04_20090920
Changed file name from phduino.h to pHduino.h.
Added codename version.
Added function to set the pH range for the pH alarm.
AddedCarloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com9tag:blogger.com,1999:blog-1033721154498518542.post-6300368222801220032009-09-13T19:45:00.009-03:002009-09-13T20:40:42.259-03:00pHduino Firmware v03 releasedThis is the newest version of the pHduino firmware. Now you can configure it using a serial port communication.Fixed comment about time of one 60Hz cycle in phduino.h file.Added time for 50Hz power line.Added command line feature to configure the pHduino.Added option to work without temperature sensor by setting a temperature value by command line.Added option to configure the time interval Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com4tag:blogger.com,1999:blog-1033721154498518542.post-38699802421390484122009-08-30T21:09:00.009-03:002009-09-01T00:14:01.047-03:00pHduino 0.2 releasedA new pHduino hardware version was released. The problem about sensor voltage offset compensantion was resolved. See the changelog for the changes.Changelog - Hardware version 0.2Fixed the problem of the offset signal amplification before the compensation.Increase the value of the resistors to reduce the electric current consume (Dr. do Lago).Changed the charge pump inverter capacitors from Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com11tag:blogger.com,1999:blog-1033721154498518542.post-13469219371655452702009-08-17T21:12:00.006-03:002009-08-17T21:47:39.341-03:00Error with the gain stageI said that I decided change the gain stage from a trimpot to a resistor to simply the calculus, but now I made a mistake about the gain stage.My first version used a trimpot for the offset stage and another one to the gain stage. In this configuration I can adjust the signal with freedom. The code is simple and easy to change. But, I can determine exactly the gain value. This is the point Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com5tag:blogger.com,1999:blog-1033721154498518542.post-77439165529901850052009-08-11T23:38:00.000-03:002009-08-11T23:59:10.877-03:00Circuit releasedI am really sorry about the delay. But, just before to publish the electronic schemes and the PCB layout I decided to make some changes. Now I published the first public version of the pHduino hardware scheme and PCB. I have a code example but I need clean it up.One change was remove a gain adjust trimpot to a fixed value resistor. This change makes me know exactly the voltage of the glass Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com0tag:blogger.com,1999:blog-1033721154498518542.post-65647845841380589692009-08-04T23:22:00.000-03:002009-08-05T01:48:16.700-03:00pHduino - An pHmeter using Arduino BoardAboutpHduino is a open hardware and open software for pH measuments using a glass electrode sensor for hydrogen ion and a Arduino board.HistoryJust after I returned from my last post-doc project at San Antonio, Texas, I decided not restart my last project. I did it to finish some works and make an open hardware project in electrochemistry. After some tests, a friend called Denis Vidal, suggested Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com15tag:blogger.com,1999:blog-1033721154498518542.post-65859435399199511192009-08-04T00:22:00.000-03:002009-08-04T01:07:30.162-03:00First postHi everybody.I am really happy to announce the launch this project: a pH meter using a Arduino/Freeduino board.PURPOSEConstruct a pH meter using an Arduino/Freeduino board to read pH with a pH glass electrode. It is not a high resolution scientific instrument. This project aims to be simple, using resources from the Arduino, commons and cheap electronic components. The pHduino could be operate Carloshttp://www.blogger.com/profile/09088461044248860193noreply@blogger.com1