Interfacing an external ADC chip to FPGA/CPLD

Chris (from PyroElectro) has posted an article on interfacing an external ADC chip to FPGAs and CPLDs, which do not have A/D capabilities built-in. He illustrates the idea with an Altera EPM7128 and a MAX150 8-bit analog to digital converter IC. The test analog signal is derived using a potentiometer and the converted digital output is shown using an LED bargraph display. The interface between the CPLD and ADC has been implemented in VHDL.  

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Digital logic probe for troubleshooting TTL and CMOS circuits

A logic probe is considered as a stethoscope for engineers and technicians for debugging digital logic circuits that consists of logic gates, memories, registers, etc. A digital multimeter (DVM) can also be used for such analytical purposes but it gives you the numeric value of the voltage at a point instead of the logic state. Depending on whether the circuit is based on TTL or CMOS components, the voltage levels for logic 0 and 1 could be different for each family. DVM users, thus, have to calculate logic levels from the measured voltages, which consumes time and delays the troubleshooting procedure.

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Lab 21: Servo motor control

A servo motor is a special geared DC motor equipped with an electronic circuit for controlling the direction of rotation, as well as the position, of the motor shaft. Because servo motors allows precise angular positioning of their output shaft, they are used extensively in robotics and radio-controlled cars, airplanes, and boats to control the motion of their various parts. In this lab session, we will first explore what a servo motor consists of and how it works and then illustrate how to interface it with a PIC microcontroller.

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Using CMOS camera for sensing applications

Ibrahim Kamal from IKALOGIC informed me about his latest article on the use of CMOS camera for sensing applications posted on his website. It’s true that interfacing a CMOS camera with 8-bit microcontrollers has not been very common. There’s a stereotype that much faster and powerful microcontrollers are required to process the output of a CMOS camera, which may not always be true, as illustrated by Ibrahim Kamam. In fact, it all depends on the type of application you choose with a CMOS camera. The article discusses about the possibility of using a CMOS camera for sensing applications by reducing

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Another LUX meter using MAX44007 ambient light sensor

In his digital light meter project, Shawon Shahryiar demonstrated a technique of using a normal LDR to construct a simple LUX meter that outputs the ambient light conditions on an LCD display. While this technique is simple and cost-effective, it requires an additional reference photometer to calibrate the LDR first adding an additional step. I came across this another LUX meter project on University of Wisconsin-Superior website that eliminates the need of external calibration and provides very precise measurement of illuminance in the range of 0.025 – 99999 LUX. This project uses Maxim’s MAX44007 ambient light sensor which features an

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