RFduino connected to HC-05 bluetooth
I was looking for a system able to work with an iPhone (Bluetooth Low Emission – LBE) and a standard android (Standard bluetooth / rfcom). The RFDuino Arduino platform I have is perfect for BLE so, I decided to add a HC-05 module for the standard bluetooth.
Here is the description on how to make it !
Really interesting tweet I just saw about the Odroid-U3 platform you can find following this link. This platform with the size of a Raspberry PI board is a 4 ARM core 1.7Gb (cortex A9) with 2GB included. Video is HDMI 1080p.Storage is MicroSD slot. The price is really low : 58$
You can ran even Android & Linux on it.
Compared to a RPI, this sound good for video/media box applications, better than RPI. For hacking this is largely different, as you can see on the picture, GPIO connector are not so easy to access. But, you can also purchase an extension shield providing all what you are expected with 36 GPIO. To build your own shield it could be more complicated than RPI. This let me go to a question I have since months … Why RPI is not becoming less and less expensive or more & more powerful ? it have now about 2 year old.
Less negative point : like any new board coming after Raspberry, the ecosystem is actually really smaller and all third party components (box, shields) is really limited.
Now, that said … I have to order one !
ODROID-U3
The RfDuino arduino device i’m actually hacking is a bluetooth 4 (BLE) device. I was expecting to work with it as any bluetooth devices in a terminal session like with rfcomm in previous version of bluetooth.
In fact not ! BLE are not pairable as the classical BT device, they are discovered by the application itself. Then you have communication channel you can read or write to communicate.
Thanks to a post in a forum, I’ve found a really usefull tool lightblue allowing to connect any BLE device and send it data. This soft works on iOS and MacOsX.
You can also get Apple tool : Bluetooth explorer and Packet Logger here.
With the 16×16 123RGB panel base on WS2812b, I have 256leds able to consume up to 50mA each. I want to use this with a limited current under 3A and want to ensure using software, this limit will not be reached. This article detailed my code for doing this.
Each led value is stored in a int array where each value is containing rvb values.
As described in a previous article, I’m investigating ws2812b leds provided with RGB123 board. These leds are providing a lot of light, which is a good thing but also require large power supply to light them on. As in my system, I want to control power to not overload the battery, I’m tring to predict current need and limit it.
In fact, the final equation is really easy to get. According to my different measures, the current is really linear for each of the color, equal for each of them too.
As a consequence, the final current estimate is :
I(mA) = 1 + R/16 + G/16 + B/16
After installing openstack on CentOS with RDO package (installation I recommand as it is really easy) I had some issue with network : the bridges were not connected to the physical network and well configured so I was not able to communicate with any VM created.
Here is how I solved this issue …
A lot of you are coming to my blog for RF433 with Raspberry PI content (here). This article is a small part of a larger project I have. As part of this project I built a Raspberry Pi shield including an RF433 emitter and receiver. I could sell this shield to some of view if it make interest to you. To make it I selected emitters and receivers to get the best quality / price compromise. (read my other articles on this topic) I could sell it around 60€ + port.
Update : chek this article for all informations on the shield and buy it !
RF433 shield for Raspberry PI v0.1
My question to you is : would you be interested in a such thing ?
If yes : leave me a comment with your email address ( I’ll will remove this address before validating it )
RF433 Raspberry PI shield v1.0
Here is the Version 1.0 with antenna connector integrated to PCB.