Deployable Generic Wireless Sensor Interface and Controller
The AIRcable S.D.K. (Sensor Deployment Kit) is our latest product based on the AIRcable SMD, designed to be a deployable generic wireless sensor interface and controller. It is already pre-programmed in BASIC code to perform:
- sensor reading
- data logging
- display data and user interaction
- communication to and/or from other Bluetooth devices and servers
- make decisions and control equipment
It consists of two parts, display / processor module and a generic sensor module, which can be customized to fit an application. Together they make up the AIRcable S.D.K., a deployable generic wireless sensor interface and controller in an attractive housing design.
- Plastic Housing
- LCD, 8 characters alphanumeric
- 3 buttons, left, middle, right
- 3 LEDs, green, red, blue
- AIRcable SMD with external antenna
Basically, the display module is an AIRcable SMD with an 8-character LCD and a generic connector. It maps a number of AIRcable SMD pins to the outside. The red and blue LED are connected to the standard LED drivers on the SMD and the right and left buttons are connected to the parallel PIO2 and PIO3. The green LED is connected to PIO8. The middle button is used for power on and interrupts.
The generic connector has 2 analog inputs, with AIO0 already showing battery voltage (VBATT). It has I2C interface, speaker output and asynchronous input/output (RS232). The two buttons, right and left as well as all 3 LEDs are available on the connector as well. Free accessible PIOs are: White (PIO10), PIO0 (or PIO11), PIO1 (or PIO12).
|1||VIN||5V regulated input for battery charging||12||SCL||I2C port clock|
|2||VBATT||LiPol Battery pole||13||SLEEP||PIO 4, pull low for enable RS232, high for allow deep sleep|
|3||1V8||accurate 1.8V reference voltage||14||LEFT||active low button , PIO 3|
|4||RX||TTL level RX for asynchronous receive data||15||RIGHT||active low button, PIO 2|
|5||TX||TTL level TX for sending out of the SDK||16||PIO 1||PIO 1 (BC5C2: PIO 12)|
|6||AIO1||analog input, 1.8V max||17||PIO 0||PIO 0 (BC5C2: PIO 11)|
|7||AIO0||analog input, battery voltage||18||GREEN||PIO 8|
|8||MIDDLE||middle button, active high, PIO 11 (BC5C2: PIO 16)||19||WHITE||PIO 10|
|9||SPKRP||Speaker differential output plus||20||BLUE||PIO 19|
|10||SPKRN||Speaker differential output negative||21||RED||Hardware controlled but also on PIO 9 (BC5C2: PIO 18)|
|11||SDA||I2C port data||22||GND||Ground|
A special pin is SLEEP, which is connected to PIO4. This pin can be used to allow deep sleep of the processor, when very low power consumption is required. While the processor still waits for ALARMS and for one INTERRUPT pin, the power consumption can get under 50uA. The PIO4 (SLEEP) pin has to be held high to allow that. To use the USB interface to RX/TX, SLEEP has to held low (A = pioclr 5).
The connector also has power input for the AIRcable SMD, rechargeable battery connector and 1.8V reference voltage.
To achieve best range possible, the display module has an external antenna. Range is over hundreds of meters.
Generic Sensor Module
- plastic board carrier, mountable on the wall
- wide range power supply (5-25V)
- rechargeable battery
- real time clock
- 3 power switches (cold side mosfet, 1A)
- USB interface for power (charging and UART serial communication to the SMD)
- play-area to add your own electronics
We made a simple, generic sensor board to attach various sensors for any application. The display module will connect directly to the sensor module and the plastic snaps together for a complete sensor and control application.
There are two ways to power the display board, either with a 5-25V DC power supply, which can be also a standard 12V solar cell. A 3W solar panel is perfectly fine to charge the Lithium Polymer battery.
It also has the option to connect a USB cable. The display module gets the 5V power to charge the batteries and also has a USB-to-serial interface available. The PC can read debugging information for example on the serial port of the AIRcable SMD.
A real time clock, powered from the battery and available from the AIRcable SMD software is on board as well as 3 power switches. These are power mosfet transistors on the cold side (connect to GND) switched by PIO0 (or PIO11), PIO1 (or PIO12) and the green LED (or PIO8). Whenever the green LED is on, the transistor switches a power to GND, to start a motor for example.
We have already put one temperature sensor on the board, installed on the free area with standard 0.1 inch solder points. It is attached on VBATT for power and on AOI1 for the linear voltage temperature reading.
In this example, the TMP36GT9Z temperature sensor is used, powered by the battery and provide a voltage, linear to the temperature attached to AIO1. The AIRcable SMD reads the voltage (max 1.8V) and display temperature on the LCD. Other sensors can be used instead, e.g. a distance sensor, or humidity sensor etc.
Multiple analog inputs can be realized with a transistor switch, like the mosfets used for the output to select multiple sensors. The 1.8V reference available allow the use of cheap NTC type temperature sensors.
We also have an I2C interface available. This allows the use of many ADCs and other type sensor/control interfaces or sensors.
Here are the production files for:
- Main Board Schematics
- Sensor Board Schematics
- Eagle files for your own development: AIRcableDevKitEagle.zip
- Download the AIRcable Sensor Server VMware image here: AIRcableServerVMware.iso
The AIRcable S.D.K. is programmed in BASIC using the comprehensive AIRcable Sensor BASIC Framework.
The latest source code is available here: AIRcable OpenSource Project
Please look at our solution-develop-example page for how to use the framework for very easy software development.