Working With LM19 Temperature Sensor
LM19 is an analog temperature sensor that operates over a while temperature range (-55 to 130 Celsius). It is very easy to interface it with a microcontroller due to is fairly linear voltage output.
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A Library for LTC1665/LTC1660
ATmega328p does not provide any Digital/Analog conversion channels (although the D/A conversion can be simulated by means of measuring the PWM output). We can easily add up to eight D/A channels using either a LTC1665 (8 bit) or LTC1660 (10 bit) from Linear Technology.
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An Arduino ICSP Board
I have been using the bit-banging method to boot-load ATmega328p with Arduino bootloader for a while, and Kimo’s method worked quite well for me. If you need to flash a lot of chips however, you might not want to swap out the chip on your Arduino board every single time you need to flash another chip as you do not want to accidentally damage the socket (or the board) in the process. After all, the DIP socket is not designed for this kind of repetitive use.
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Interfacing LIS3LV02DL Using SPI — II
In my last post, I described in detail how to hand solder LIS3LV02DL, an LGA packaged accelerometer chip. And here I will show you how the communication with Arduino is done using SPI.
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Interfacing LIS3LV02DL Using SPI — I
LIS3LV02DL is a MEMS three-axis digital linear accelerometer that provides both I2C and SPI interfaces for communicating with microprocessors. My work here is largely based on the work done at Near Future Laboratory. Instead of using a commercially available LIS3LV02DQ break-out board (LIS3LV02DQ is QFP packaging equivalent of LIS3LV02DL), I chose to hand solder an LIS3LV02DL (which is uses LGA packaging). And I have made some changes to the code sample to support more functionality.
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4 Digit 7 Segment Display Using Arduino
I was inspired by Paul’s 7 segment display and decided to build one myself. He used 4 common cathode 7 segment displays. In his original schematics, all the segments within a display shared one current limiting resistor which unfortunately affect the display brightness when different numbers of segments are lit. I happened to have two common anode dual 7 segment displays (QDSP-G545) so I decided to use them and four 74HC595 shift registers to build a four 7-seg display. Realizing that other people might be using either common anode or common cathode displays, I also built a library that can be used for either case.
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On ATMega328 Bootloading With FTDI Bitbang Method
I have been using the FTDI bitbang method piloted by Kimio Kosaka and improved by others (1,2,3) to flash Arduino bootloader onto blank ATMega328p for a while and thought I would share my experience with everyone.
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A Simple Dual H-Bridge
H-bridge is frequently used to control DC motors and stepper motors. When controlling a bipolar stepper motor, two full H-bridges are needed. There are many H-bridge ICs (like L298, MPC17529 and SN754410 which is a quad half H-bridge) for just that purpose. But if you are on a budget, you may want to consider building a dual H-bridge yourself.
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A Power Inverter with Arduino Pulse Source
After going through some of the tutorials on Arduino’s site, I really started to appreciate what a powerful platform Arduino really is. A lot of seemingly complex software/hardware interactions can be made quite easy with relatively few components and little coding. As one of my first Arduino based projects, I built a simple power inverter driven by Arduino.
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Hello Arduino
When I first started interfacing electronics with computers back in the early 90′s my hardware choice was an ISA AD/DA card. So when I wanted to experiment with some physical computing stuff recently, I thought of getting an AD/DA card that can be plugged into either a PCI or a PCI Express slot.
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A Parallel Port Stepper Motor Driver With Discrete Components
Using PC’s parallel port is a convenient way to control a stepper motor. For unipolar stepper motors, up to two motors can be controlled with the 8bit data line.
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An Isolated MOSFET Serial Port Relay Controller
Using DTR (data terminal ready) and RTS (request to send) pins of a PC serial port (RS-232) without actually using the serial data pins, we can interface at least two relay devices with a computer. Windmeadow Labs has an excellent article on how to achieve this using a bipolar transistor (BJT). Here I will show you a similar relay control circuit built using an opto-isolator and a MOSFET.
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