Microcontrollers
Overview
What is a microcontroller?
A microcontroller (abbreviated as MCU or uC) is a small computer built into a single integrated circuit (IC) which contains memory, processor(s) and I/O controls. They come is a vast array of packages and capabilities. The idea is to meet the engineering challenge will the appropriate level of force. If your problem consists of monitoring data or sensors and manipulating an actuator, status LEDs or to transmit then the latest Intel powered computer would be incredibly excessive, expensive and cumbersome. This is where the microcontroller comes in. It provides us a tool to complete the task cheaply and with ease.
Architectures
There are two main "houses" for microcontrollers, PIC and AVR. PIC (Peripheral Interface Controller) microcontrollers are made by Microchip Technology. AVR (Advanced Virtual RISC) is designed by the Atmel corporation and are the semiconductors that power the popular Arduino platform.
Sidenote: RISC stands for Reduced Instruction Set Computing. The idea is to use fewer, more general purpose, assembly instructions to make a device quicker and more battery efficient.
Which microcontroller should I choose?
There isn’t a cut and dry winner, especially for a beginner. Some diehard enthusiasts and professionals loyal to either brand will swear by their platform of choice’s capabilities. However, both come in such an array of price points and features that it is truly a matter of taste and comfort ability. An abundance of development boards exist for both PIC, such as our custom PIC boards, and the Atmel based Arduino Mega 2560.
For the absolute beginner, the Atmel microcontrollers can be very enticing due to the Arduino Open Source Hardware project. Due to the nature of open source there is an abundance of software libraries and hardware extensions (shields) available. This provides a strong foundation for the beginner to build on top of and get started in the world of microcontrollers.
About PICs
A Brief History
The original PIC was built to be used with General Instrument's new 16-bit CPU, the CP1600. While generally a good CPU, the CP1600 had poor I/O performance, and the 8-bit PIC was developed in 1975 to improve performance of the overall system by offloading I/O tasks from the CPU. The PIC used simple microcode stored in ROM to perform its tasks, and although the term was not used at the time, it shares some common features with RISC designs.
In 1985, General Instrument spun off their microelectronics division and the new ownership cancelled almost everything — which by this time was mostly out-of-date. The PIC, however, was upgraded with internal EPROM to produce a programmable channel controller and today a huge variety of PICs are available with various on-board peripherals (serial communication modules, UARTs, motor control kernels, etc.) and program memory from 256 words to 64k words and more (a "word" is one assembly language instruction, varying from 12, 14 or 16 bits depending on the specific PIC micro family).
PIC Programming
PIC microcontrollers have an array of development environments available for both the beginner the professional. MPLAB’s IDE is open source and can be found on MicroChip’s website. Other paid alternatives are MickroC Pro which allows you to program your microcontroller in C, or Microcode Studio for Basic.
Getting Started
We design and produce an array of custom PIC development boards to allow easy programming and interfacing with video, servos, motors, and various communication protocols (RS232, RS485, TTL, etc). You can choose one of our stock boards, or commission your own to suit your specific needs.
About AVR and Arduino
A Brief History
The AVR architecture was conceived by two students at the Norwegian Institute of Technology (NTH) Alf-Egil Bogen and Vegard Wollan. The AVR architecture was later bought by Atmel Corporation in 1996.
The original AVR MCU was developed at a local ASIC house in Trondheim, Norway called Nordic VLSI at the time, now Nordic Semiconductor. It was known as a µRISC (Micro RISC) and was available as silicon IP/building block from Nordic VLSI. When the technology was sold to Atmel from Nordic VLSI, the internal architecture was further developed by Bogen and Wollan at Atmel Norway. The designers worked closely with compiler writers at IAR Systems to ensure that the instruction set provided for more efficient compilation of high-level languages.
Getting Started
When getting started with Atmel and the Arduino platform, we suggest looking at the Arduino Mega 2560 as it’s compatible with anything designed for the Arduino Uno or Leonardo but with additional analog and digital I/O. This will allow for greater flexibility with the development board.
The Arduino Mega 2560 development board is equipped with:
- Microcontroller: ATmega2560
- Operating Voltage: 5V
- Input Voltage (recommended): 7/12V (Center positive 2.5mm barrel plug)
- Digital I/O Pins: 54 (with 15 PWM capable pins)
- Analog Input Pins: 16
- DC Current per I/O Pin: 40mA
- DC current for 3.3V Pin: 50 mA
- Flash Memory: 256 KB
- SRAM: 8 KB
- EEPROM: 4KB
- Clock Speed: 16 MHz
Arduino Programming
Arduino microcontrollers can be programmed with their Arduino IDE (integrated development environment) which allows you to program the microcontroller in a programming language similar to, C. Provided with the IDE are several examples to get you started. For specific issues you man run into, please see their forums.
Product Families
AVR has multiple product families rangining from 32 bit down to 8 bit microcontrollers.
- tinyAVR (8-bit)
The AT Tiny product line is the smallest line that Atmel offers. Running at 8 bits and down to a mere 0.7 volts, it provides a cost effective solution in a small package. - megaAVR (8-bit)
The mega line is featured in the Arduino Mega 2560 development board and is Atmel’s broadest family. It provides high integration of serial, I2C and USB protocols, analog capabilities with a low power consumption. - AVR xMega (8/16 bit)
The xMega family is a step up from the Mega. It boasts a higher performance ADC and a broader software library to take advantage of its 16 bit instructions. - AVR UC3 (32-bit)
The UC3 microcontroller line features a 32 bit instruction set, USB, Ethernet MAC, SDRAM, NAND flash, Floating point arithmetic and an expanded software library. The UC3 family has a broad series of chips for specific applications such as audio specific applications, high throughput, touch interfaces, motor controlling and communications.
Need Customization?
With our team of electrical engineers, we provide custom microcontroller boards based on your needs. Here's a look at the boards we currently offer.
Remote Control Board
A custom made PIC microcontroller board based on the PIC16F887 microcontroller. It supports 10 analog I/O and 14 digital I/O. To interface with the board a five pin header is provided.
Specifications
- 12V input
- 5V (2), 9V (2) and 12V(8) outputs
- 1 Hardware and 1 Software UART
- 4A polyswitch
- PIC16F887
- Status and power LEDs
- Peizo Speaker
- 9 Analog Outputs
- 14 Digital outputs (7 with optional pull-up and pull down resistors)
Dual UART Control Board
A custom microcontroller development board based on the PIC 18F6622 microcontroller. The board supports the RS485, RS232 and I2C standards for communication. For programming, a 5 pin header is supplied.
