Debraj have shared his latest project details where he built an OBD reader. As his car (Hyundai -i10) uses CAN-BUS communication protocol naturally it is based on it. To be more specific CAN runs at 500kbps speed and uses 11-bit ID.
The reader is based on dsPIC33FJ128MC802 microcontroller and MCP2551 CAN transceiver. Information is displayed on standard four row alphanumeric LCD. His further plans are to add SD card to collect some interesting data while driving.
If you always fancied about the laser light shows, but you’ve no ideas how to develop one for yourself, then you must pay attention on today’s topic, as it’s about the dsPIC-based Laser Light Show Controller!
This dsPIC-based Laser Light Show Controller can also be known as an arbitrary waveform generator (ARB). For your information, the controller will allow vector patterns to be stored in flash program memory or uploaded from a PC in a vector format. The analog output via two 14-bit DACs has being fed to a commercial analog driver board and two high-speed galvo scanners.
For the project, you need to use a Microchip dsPICDEM starter demonstration board featuring a 30F6012 processor chip. The best things about this board is it already has a prototyping area which is populated with the DACs, two connectors, voltage regulators and basic I/O circuitry (an RS-232 interface), where it simplifies the construction of the system.
Theoretically, in a basic laser light show, there will be a laser beam is deflected by two galvanometer scanner heads, where each of them moves a mirror to steer the beam in horizontal and vertical direction continuously.
The entire system is usually a PI or PID (Proportional Integral Derivative) control loop with the output fed to the galvos and feedback supplied via a capacitive sensor inside the galvo scanners. Furthermore, the driver or control loop is usually accepts analog signals.
There are different types of microcontrollers in the PIC family and one of the most familiar PIC families would be the dsPIC33.
The reasons why the microchip dsPIC33 frequently being used in the digital signal controller related projects because it runs at 40 MIPS, and with up to 256 Kbytes of self-programming Flash, more than 30 Kbytes of RAM and 64 to 100-pin packages. Beside that, it’s including an 8-channel non-intrusive DMA and the option of 1.1 Msps high performance A/D converters too!
Today, you will try to apply this dsPIC33 into a breakout box or BoB, which it’s usually a box that a compound electrical connector is totally separated into its component connectors.
Basically, the compound connectors are used where sufficient space for connections is unavailable, such as on personal computer sound cards! This means if there are only a few connections, then a breakout cable will be used here, as it’s a common matter on a smaller notebook computers.
For your information, a breakout box can also mean a piece of electronic test equipment, which has been used for diagnosing problems in computer communications, especially over a serial port.
Do you have a dsPIC oscilloscope and Spectrum analyzer in your lab, but you still think that you didn’t fully used it for a great purpose?
Well, then it’s time to use some of your creativity and effort to combine these two stuffs together and transform it into a magnificent Scopey II!
Before it, do you know the main function of the Spectrum analyzer? Technically, it is a device used to examine the spectral composition of some electrical, acoustic or optical waveform. Sometimes, it can be also measured the power spectrum as well! Basically, the spectrum analyzer can be divided into two main types and there is analog and digital spectrum analyzer.
This is how the Scopey II works…
Everything is comes in through the BNC jack on the front and the signal is than attenuated or amplified by the attenuator and amplifier. The gain of the input stage is fully controlled by the PIC and the input stage level will shift the input so it can centers around 2.5v to enable reading negative voltages. Furthermore, the ADC is also reading the front panel controls. As the result, all the exciting information, where the PIC gathers is displayed on a handy 128×64 graphics LCD!