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]
A beginner’s guide to AVR programming on instructables. It cover the basic setup to light up some leds.
Beginner’s Guide – AVR Programming - [Link]
Martin Thomas shows us how to interface Atmel AVR witg graphic LCDs:
This is a C-library for avr-gcc/avr-libc to access SED1520-based graphics-LCDs. The modules used to develop the library only support “write to LCD”, read-modify- write on the display RAM is not possible. So this Library uses a “framebuffer” which holds the display-content in the AVR’s SRAM. For a 122*32 pixel display around 500 Bytes of SRAM are occupied by the buffer. The library does of cause support modules which can be read in “write-only-mode” (tie the R/W-Pin to GND).
Interfacing Atmel AVR with Graphics Liquid Crystal Displays (GLCDs) - [Link]
Over a week ago I’ve got a notice that Texas Instruments (TI) is giving away a 50% coupon for MSP430_FRAM related devices. Without hesitation ordered their MSP-EXP430FR5739 TI experimenters board that price went down to $14.50 including free shipping.
MSP EXP430FR5739 FRAM based microcontroller board is interesting piece of hardware. It features FRAM memory instead of Flash which is claimed to withstand almost unlimited number of Reads and Writes. It is also faster. It can substitute an EEPROM on board. But it is not very popular technology due to different manufacturing. On this development board there is MSP430 microcontroller which has 16KB FRAM, 1KB of SRAM. It carries eight LEDS, MTC thermistor, 3 axis digital accelerometer, optional LDR, couple buttons. So this is great for many uses.
Experiment with MSP430 FRAM board via web interface - [Link]
Microchip Technology Inc today announced from EE Live! and the Embedded Systems Conference in San Jose the PIC16(L)F170X and PIC16(L)F171X family of 8-bit microcontrollers (MCUs), which combine a rich set of intelligent analog and core independent peripherals, along with cost-effective pricing and eXtreme Low Power (XLP) technology. Available in 14-, 20-, 28-, and 40/44-pin packages, the 11-member PIC16F170X/171X family of MCUs integrates two Op Amps to drive analog control loops, sensor amplification and basic signal conditioning, while reducing system cost and board space. These new devices also offer built-in Zero Cross Detect (ZCD) to simplify TRIAC control and minimize the EMI caused by switching transients. Additionally, these are the first PIC16 MCUs with Peripheral Pin Select, a pin-mapping feature that gives designers the flexibility to designate the pinout of many peripheral functions. The PIC16F170X/171X are general-purpose MCUs that are ideal for a broad range of applications, such as consumer (home appliances, power tools, electric razors), portable medical (blood-pressure meters, blood-glucose meters, pedometers), LED lighting, battery charging, power supplies and motor control.
Microchip Releases 8-bit PIC Micros with Intelligent Analog and Core Independent Peripherals - [Link]
Raj Bhatt from Embedded-Lab has posted a detail review of mikroElektronika’s EasyPIC v7 development board (http://www.newark.com/mikroelektronika/mikroe-798/development-system-easypic-v7/dp/63W4082) on his website. EasyPIC v7 supports over 350 PIC microcontrollers including PIC10F, 12F, 16F, and 18F, and contains an onboard fast USB programmer and real-time debugger. The board also features two mikroBUS sockets for tons of other add-on boards, thus expanding its capabilities.
[via the contact form]
Review of EasyPIC v7 - [Link]
A purely software based USB peripheral for ARM Cortex M0+ devices. This software enables Cortex M0+ devices to act as Low speed USB device. It includes a lightweight USB & HID Stack and easily be optimized to consume only 4KB of flash.
LemcUSB: software USB for EFM32ZG (ARM Cortex M0+) - [Link]