Why pay hundreds for a commercial Data Acquisition System when you can build the PIC DAS for less than $50.00? The PIC DAS is built around a Microchip PIC16C63A microcontroller and contains an 8 bit bidirectional Digital I/O port, 12 bit, 8 channel A/D converter and a 12 bit, 4 channel output D/A converter. It is perfect for quickly controlling any project on your workbench! Use the Digital I/O to sense switch closures with the help from the built-in weak pullups, control OPAMP’s, power supplies and the like with the built-in D/A converters.
Measure temperature or sense voltage or current with the built-in A/D converter. The real usefulness of this system is that it has a known simple to use interface that uses real ASCII commands over an RS232 link. This method of control saves programming time that would otherwise be wasted controlling the test setup, instead of actually doing the test.
The author, Olivier de Broqueville designed this circuit for hi’s son who was dreaming of a small tool able to write symbols or pictures on a screen. The solution adopted was to pilot a matrix of Leds. This way, with only some cheap transistors, common red Leds, and a 16F628 , the dream could become reality.
Olivier also made a VB application that you can use to design patterns and export them apropriately.
The LED cube runs using a PIC16F690. Along with the brief explanation of how to make it, the author has also included the .asm file for the PIC and a piece of software written in VB.NET that you can use to create your own LED patterns. These can be exported as .asm files and put into the main .asm code.
This 3-digit digital thermometer is easy to build for beginners or hobbyits. PIC16F628 is used to read digital values of temperature from a DS1820 sensor. All 7-segments are driven by a power logic 8-bit shift register TPIC6B595 with open collector output. For the 7-segment we need 12V volt to drive it because it has 3 LED per one segment. Source code in C Compiler is available.
It’s a good idea to use LCD’s with projects like this instead of led digits, because LCD’s don’t need to be refreshed, they allow you to display many characters and it requires less I/O pins. In this project a 16×1 LCD Display with 4-bits interface it’s used. Time and date are displayed as HH:MM:SSx mmm dd, where: HH = Hours MM = Minutes SS = Seconds x = AM/PM mmm = Month (Jan, Feb, Mar) dd = Day.
