Once you start building something with microcontrollers, one thing you need to take in to account is programming adapter. This is a device which allows to upload compiled code in to chip. I don’t know if this is still a fun to build your own DIY programming adapter which is not guaranteed to support all chips nor it will be safe and reliable. AVR microcontroller niche is one of most interesting when talking about programmers. If you take a look at AVRDUDE configuration file you will find that there is about 50 of them. Many of them are DIY while other are official.
Choosing right programmer for AVR microcontrollers - [Link]
This is a complete mobile MP3 player and first mp3-player with ATmega8 and Nokia 6100 color display.
An demo firmware and gerber file for board will be available soon.
This player has capability to play wav and mp3 files and view BMP files on 8 or 24 bits/pixel from a MicroSD card with maximum capacity 2GB, the format of the SD is FAT32 with clusters from 512 Bytes to 32768Bytes, the filesystem has no limits in number of directories and files.
For future i want to adapting the SD driver for SDHC because the filesystem is designed to use all capacity of fat32 ( 2TB in 512Bytes/sector)
List of features:
Play Wav and MP3 Files because the VS1011a only this files is capable to decode( but for future in this project i want to include the VS1053 chip to play more file formats.
View Bitmap files on 8Bit and 24 bit/pixel
This project is in asm language and my 100% own libraries
DiY: most tiny MP3 player with ATmega8 VS1011a and Nokia6100 Display - [Link]
ISPnub is a simple to use stand alone programmer intended for flashing AVR controllers in the field directly in the target system or during production. The module has only one button and two leds as user interface.
- No external power supply needed. Uses voltage provided by target (1.8V to 5.5V).
- Programming counter. Limit possible programming cycles. After allowed cycles, no further programming is possible (module has to be erased/reprogrammed).
- One-button-programming: connect – push button – wait for red led off.
- Simple LED schema:
- green on = ok
- green blink = counter expired
- red on = programming
- red blink = error
- Define programming with simple script. Script converter generates HEX file for module.
- Load module with any ISP programmer which supports ATmega1284p
- 120kB memory space for programming data
ISPnub – Stand-alone AVR In-System-Programmer Module - [Link]
Marcus Linderoth built a clock using a TI MSP430g2553 microcontroller and a HPDL-1414 display, that is available at Github:
After having ported Contiki to the Launchpad, I was eager on doing something with it. I built this simple clock with a vintage HPDL-1414 “smart four-character 16-segment alphanumeric” display and a msp430g2553.
Clock with retro display - [Link]
hardwarehank @ instructables.com writes:
The Atmel ATTiny85 chip is an 8-pin MCU that is totally awesome. If you’ve been programming with the bigger boys (the ATMega series), these are a nice adventure – you’re rather limited in the number of output pins, but a creative design gives us a lot of flexibility in a very small package.
You’ve seen them – those “Apple computers.” Probably in the hands of some Hipster in Portland, while riding his fixie and wearing those thick framed glasses. That pulsating light when Apple laptops are asleep is so … sooooothing. You just want to go to sleep watching it. You know you do.
Today, we’re going to replicate that using our ATTiny85. It’s really easy, and most of it can be implemented in hardware instead of code (!!!).
Apple-style LED pulsing using a $1.30 MCU - [Link]
To satisfy electronic DIY hobbyists, ICStation has developed MAX7219 Dot Matrix Module. It uses the Max7219 chip which do a great job on saving of MCU I/O. It can not only control each point individually, but also can be extended without limitation to meet your requirements on LED Sign, Team Logo and so on.
What’s more, it’s controlled by the STM8S003F3 MCU with 1K data storge space which is low cost, low power consumption, very powerful.
DIY LED Sign with MAX7219 Dot Matrix Module - [Link]
Acidbourbon posted a step by step guide of his digitally controlled HIFI amp with 4 way mixer build:
The amplifier section is trivial. You just buy a TDA1554Q, bolt it to the inside of an aluminum box, solder some resistors and capacities to the pins of the IC according to the application note in the datasheet and you have a small HiFi amplifier.
Because the volume control has to be digital, I’m using digital potentiometers. Sadly there are no (affordable) logarithmic digipots available. However I found this method which employs a linear potentiometer in combination with a fixed resistor to “fake” a logarithmic potentiometer.
Digitally controlled HIFI amp with 4 way mixer - [Link]
by Claude Haridge:
Microcontroller-based products sometimes require rotary switches. As many microcontrollers have an onboard ADC, it is easy to replace the rotary switch with a low cost potentiometer, when a rotary switch is too expensive or unavailable.
Although digitizing a potentiometer setting to act like a switch requires only a few instructions, an immediate problem is that instabilities in value occur at the switching threshold between one value and the next due to electrical or mechanical noise. The solution is to introduce upper and lower hysteresis thresholds about each transition so that the potentiometer needs to move beyond a threshold before another switch state is validated. For every updated switch state, another pair of thresholds replaces the previous. In this manner, the hysteresis provides clean switching between states.
Replace a rotary switch with a potentiometer - [Link]