AVR learning

I was looking for a basic development board for the ATmega16/32 microcontrollers, I did not want one of the boards that has masses of components on the board such as LEDs, switches and LCD headers but just a bare bones board that is more like a breakout type.

Here is a picture of the board I found, it has an ISP and the ARduino RX and TX type connection (FTDI and other devices as well). There is a reset switch, oscillator and a couple of LEDs but other than that and a few other components its as basic and bare bones as you can get, key thing is that all of the ports are connected to headers and clearly labelled.

The board comes as a kit and when assembled should look a bit like this

Once built we’ll connect some LEDs and flash them on and off

Code

Similar to before, written in MikroC Pro for AVR

Source code

void main() 
{
DDRD = 0xFF;     // set direction to be output
 
while(1)
{
PORTD = 0x00;
delay_ms(1000); // Wait for 1s
PORTD = 0xFF;
delay_ms(1000); // Wait for 1s
}
}

Testing

I connected a USBAsp to the board and tried to see if I could detect the microcontroller type.

As you could see no problems here, so I then connected a couple of LEDs to PORTD and programmed the device. The LEDs flashed on and off as expected

Links

More details from http://rkeducation.co.uk/RKAT40c-mcc.php, kit comes in at £3.99 from their online store

When I was looking at products to buy I saw this little board which is commonly referred to along the lines of ATMEGA32 Minimum System Board AVR Development Board.

The product looked quite a nice little board for prototyping due to its minimalist approach and size. There are 4 switches and 8 LEDs on board that can be used and all I/O from the ATMega is brought out to a header. Here is the board pictured below

ATMEGA32 Minimum System Board

Features:

– MCU is ATMEGA32L
– System clock 16MHz
– Onboard 3.3V LDO, power indicator lamp, 8 LEDs, one Reset button, 4 independant button, reserve asynchronous clock interface, USB power supply interface.
– Pin out all 32 IO port, jumper choose 3.3V/5V voltage, 6 pin ISP download port, JTAG interface
– Could download directly from USB port

As usual this appears to be a mass produced Chinese developed board with very minimal instructions, now its not the most complex to understand but a schematic is still useful. Anyway I’ve dug up some information. First of all here is the schematic

Atmega minimum board schematics

Looking at the schematics the LEDs are all connected to PORTB, so we will flash these on and off, a sort of hello world type test

Code

This example was written in Atmel Studio

Source code

#ifndef F_CPU
#define F_CPU 1000000UL // 1 MHz clock speed
#endif
 
#include <avr/io.h>
#include <util/delay.h>
 
int main(void)
{
	DDRB = 0xFF; //Nakes PORTC as Output
	while(1) //infinite loop
	{
		PORTB = 0xFF; //Turns ON All LEDs
		_delay_ms(1000); //1 second delay
		PORTB= 0x00; //Turns OFF All LEDs
		_delay_ms(1000); //1 second delay
	}
}

I use a USBAsp programmer with this board, it uses the 6 pin pinout. i actually setup Atmel Studio to program the board using USBAsp

Links

These work out about $10 per piece
2PCS LOT ATMEGA32 minimum system board+Free shipping