Hi! First of all, Happy New Year 2017! I hope all of yours starts the new year with good intentions. The mine one is write frequently here. Family and work don’t let me much free time but I’ll try it!
For several months I’m working with FONA808 modules from Adafruit to make a portable, web-based locating system. This modules are based on the SIM808 module from SIMCOM manufacturer, and integrates both GSM and GPS transceivers in one 24x24mm package. The Adafruit board includes this module and also some electronics for choosing voltage levels, battery connection and charger. Because I need to test and programming some of this modules, I decide to make an specific PCB for it, allowing the programming and debugging via PC, wich is more comfortable that use a microcontroller for all these tasks. I use the MCP2221 USB-Serial bridge and add some electronics to give the board more functionality. So it has a connection for a 3.7Li-Ion battery, battery charger, manual pushbutton to turn on/off the module and also several led’s to indicate the status of the different elements and network connections. So, let’s go for it!
Hi all! I’m continuing here with the last board I design and now I’m continuing testing. It’s a battery-powered small datalogger based on a PIC18F2620 microcontroller. The idea comes a few months ago, talking with a friend. He needs something to monitoring temperature and humidity inside a sea container, for a three weeks travel from Spain to China. Low consumption is important, in order to have maximum autonomy with a small battery. I use a HDC1050 temperature and humidity sensor, and a TEMT6000X01 ambient light sensor. The collected data is stored on a micro SD card. Also the board has a RTC for timestamp, a Li-Ion battery charger, user pushbuttons and leds, and a MCP2221 USB bridge to communicate with the board and configure some parameters through software. Let’s see the board in detail!
Hi all! After a couple of months with a lot of work, I come here again with the last board I develop before Christmas. It’s a dual USB serial and I2C converter based on two MCP2221Microchip 2.0 USB-Serial bridges. I develop it as a need on my work with the last project I’m involved. I need to monitor a serial communication between two devices. With only one converter, I must choose between RX and TX lines to monitoring the traffic. With this solution, I can listen at the same time TX and RX lines, so the monitoring is more easy. And with a software like Docklight (you can download a free evaluation copy here), you can choose the monitoring option to display both channels. After the break you can find all the technical info of the board!
Hi all! Here’s the new project where I’m working a couple of days. Since I develop the SIM900 module and test it, I don’t work with it. Also, I’ve got at home some samples of the MCP2200 USB bridge that I want to test it. So make an USB interface for this board was the perfect idea! This allows to use the SIM900 board with a PC, Raspberry or similar, with the plus of no need external power supply or control signals. Just plug the USB cable on the board and start communicating with the world!
UPDATE: Thanks to Rando, now you can order this PCB on OSH Park. Thanks!!
UPDATE: If you’re interested in mount the board yourself, now you can download the Bill Of Materials (BOM). Happy welding!
Hi all! With a bit of delay, here’s my last work, a PICnano breadboard based on the PIC18F2550 microcontroller. I have in mind a new project and I want to use an small board, like the Arduino Nano board. This new project is battery powered (3,7V Li-Ion battery). After checking the schematics of the Arduino Nano, I see that the microcontroler is powered at 5V. Of course, I can unmount the linear regulator (U3) that is on the board, and bypass the VIN to the microcontroller power supply. But I think it’s funny try to develop a new module when you’ve access to the microcontroller power supply! Also, I want to work with PIC microcontrollers after many years, so here’s what I design!
UPDATE: This board appears on Adafruit’s blog. I’m very happy with this, it’s a great recognition and I only can say Thanks!!!
I’m continuing working with Juan Brito and Danny Macancela from the blog Desafio Ecuador, developing new boards to bring near the technology and programming languages. Our last work is a board to use with the Raspberry Pi and focused to learn Python. The board has the basic elements to start with this language. Also, with the develop of the PCB we remove the wiring, avoiding troubles with connections, inversion polarity…So with this board you only focused in the software develop, because the hardware side will work!
Normally, when I start a project, I use prototyping boards to mount the components and develop the software. When the project is finish, I always have the same trouble: in witch box or enclosure I put the electronics? If you don’t have this in mind at the start of the project, it could be a serious problem. In these years, I discover that is more easy to first find and enclosure and then develop the electronics that do it backwards. Also, I usually develop systems for both indoor / outdoor, so protection against rain and humidity usually it’s a must. For these reasons, I decide to find a good enclosure and develop a prototyping board to use with it. In this post you’ll see the results!
This project starts a few months ago. Juan Brito, author of the blog Desafio Ecuador, contacted with me to talk about Scratch and the opportunities that gives this programming enviroment in the world of education. In his own words:
I and Danny Macancela are convinced that increase the quality of education in schools and colleges do not require big budgets by governments. This ideal of change has led us to develop this project to teach children mathematics and programming. Children can learn maths with fables. The aim of this project is the search of the human talent growth, which starts in the classroom. As Fritjof Capra says, ‘Today we have the knowledge, technology and financial resources to build a sustainable future. All we need is the political will and leadership’
From here, I also want to thank Danny Macancela for his illusion in the project and its economic support.
After some months out, I come back with my last board, the SIM900 Breakout Board. It’s a board based on the popular SIM900 GSM modem, and I design to work with the DSETA board I develop previously. Also, the board can be used without this board, I try to design it in the way that can be used with any microcontroller. From here, I want thanks to Ioannis Kedros from Embedded Day his support in the design of the battery charger, and to Sonia Muñoz, FAE from EBV, a great professional and a better friend, she always helps me when I need. So, let’s go to see what’s inside the board! Continue reading →