Sometimes we need our microcontroller to interact with more human readable information. It will be better for us if we could make it display the words not just blinking the LED. Today most modern gadget such as mobile phone and PDA, use LCD (Liquid Crystal Display) for interacting with us. In this project we will learn how to use the 2×16 LCD for displaying the room’s temperature.
Actually driving the LCD hardware directly is a complex task, but luckily we don’t have to do that; in the market they have already put it together in one package the LCD display hardware and the microcontroller that control it, so our task will be easier now as we only talk to the build in microcontroller inside. The most famous on the market is the 2×16 LCD with LED backlight using Hitachi HD44780U or the equivalent microcontroller, this 80 pins microcontroller is a special dot matrix LCD driver controller with low power consumption and able to use 4-bit data or 8-bit data interface; my suggestion is to have this HD44780U datasheet near you as we walk through this project.
AVR LCD Thermometer Using ADC and PWM Project – [Link]
It’s interesting to explore what we can do with this tiny 8 pins; 8-bit microcontroller. The ATtiny13 is the smallest and cheapest Atmel AVR 8-bit microcontroller families but yet, it’s loaded with sophisticated peripherals such as two 8-bit PWM channels and 4 channels 10-bit ADC. Although the memory is quite small; 1 K flash, 64 SRAM and 64 EEPROM but this more the adequate for most PWM and ADC application, if you need more memory, bellow is the list of other Atmel AVR 8 pins microcontrollers which have compatible pins with ATtiny13 microcontroller.
Controlling DC motor with AVR ATtiny13 PWM and ADC Project – [Link]
If you’re interested in how delta-sigma modulators and ADCs work, you should check out this excellent introduction by Uwe Beis: [via]
When looking for an introduction to delta sigma conversion I found that most explanations were from a very theoretical point of view. It took me a while to understand how Delta Sigma converters really work. So I decided to write this introduction for people who prefer circuit diagrams to reading abstract equations.
To understand what I’m talking about you should at least be familiar with:
- Standard analogue techniques (op-amps, comparators etc.)
- Standard digital techniques (latches, binary codes etc.)
- Standard ADCs and DACs (resolution, speed)
- What a low pass filter is (at least an analogue one)
- The sampling theorem (sample frequency > 2 x input bandwidth, alias effects)
Delta sigma converters are different from other converters. Note that I do not make a difference between analogue-to-digital (ADC) and digital-to-analogue converters (DAC). Both are very similar and what is realized in one of them using analogue signal processing circuitry is implemented in the other one using digital signal processing and vice versa. I will explain the delta sigma technique with the analogue-to-analogue delta sigma converter as the first object.
An Introduction to Delta-Sigma Converters – [Link]
Wichit Sirichote writes:
This is my student assignment for the class “Designing Microprocessor Based Instrumentation”. The board demonstrates the use of 12-bit ADC, writing c program with digital filtering and interface the LED display. The reading provides 0.1C sensitivity. The optional input of the ADC is available for exercise with other input signals or sensors.
Thermistor Thermometer - [Link]
Another article that might help with bench power supply designs:
Current-Sense Amplifiers with Digital Output and 60V Common-Mode Range
- Offers easy interface with microcontrollers (supports 1.8V logic) by using digital outputs
- Delivers wide 60V common-mode range for robustness under fault conditions
- Includes internal op amp/comparator that allows flexibility in system design: the internal amplifier can be used to limit the inrush current or to create a current-source in a closed loop system; the comparator can be used to monitor fault events for fast response
High-side, current-sense amplifiers with 12-bit ADC and op amp/comparator - [Link]
One of the important features in today’s modern microcontroller is the capability of converting the analog signal to the digital signal. This feature allows us to process the analog world easily such as temperature, humidity, light intensity, distance, etc; which usually captured by electronics sensor and represent it on the change of voltage level.
Analog to Digital Converter AVR C Programming – [Link]
Here is my home-made kit of ATmega32 microcontroller interfacing. The ATmega32 controller is rich with features like onboard 32kB in-System programmable flash, 1 KB EEPROM, 2KB SRAM, 10bit ADC (8 channel), SPI bus inteface, TWI (compatible with I2C bus) interface, an USART, analog comparator, etc. That’s why I’ve selected it to load my kit with all those features.
Make-Yourself ATmega32 Starter’s Kit with LCD, I2C, SPI, RTC, ADC interfaces – [Link]
Here is a small project of Analog to Digital Converter using ATmega32 which is having on-chip 8-channel ADC.
The circuit also consists of an intelligent 16×2 LCD for displaying the value of the voltage applied at each channel. There is also a push-button to scroll through the different channels.
8-Channel ADC Project with ATmega32 - [Link]
Aim of this project is to present a way to store a large quantity of data into microSD card in files with FAT32 format. Here, ATmega32 is used for data collection and microSD interface. The data is received from in-build 8-channel ADC of ATmega32. One channel is used for reading temperature from LM35 sensor and remaining channels are used for simply reading voltages and storing them.
microSD ATmega32 Data-Logger - [Link]
Back in February, we wrote a post on Analogue to Digital Conversion. Many people mentioned that it was a bit light and they would like a more advanced tutorial. Well here it is…
In this tutorial we add a second analogue input and use the ADC Conversion Complete interrupt. The circuit we are using is similar to what we used last time but has an extra trimpot and uses an ATmega168A microcontroller. The ATmega168 is now obsolete, but its replacement (ATmega168A) is almost identical.
Analogue to Digital Conversion Interrupts on an ATmega168A – [Link]