Atmel AVR Programmer USB Circuit Atmega8

Via the USB port of your computer that you can program Atmel series microcontrollers ISP port with stylish design a programming circuit. Prepared with eagle pcb circuit usb programming. are schematic drawings. To use the circuit to inspectors ATmega8 avr-doper-mega8-12mhz_a.hex need to download the file.

Atmel AVR USB Programmer

Simplified Version of AVR Doper USB Programmer simple inexpensive Parallel ISP programmer has done the job since I started working with AVR’s, but it definitely has its problems. It doesn’t work with some computers, it is slow, it is unreliable and it requires a parallel port which is getting less common. USB seemed the natural progression. I selected the AVR Doper project by Objective Development as the base for the new programmer.

Below is a 3D model of the streamlined AVR Doper created in POV-Ray using Eagle3D. I only wanted to build an ISP so I was able to lose many of the components related to HVSP. I rounded the edges and scaled the board to fit in an Altoids tin.

I modified the Objective Development schematics and circuit board using the free version of CadSoft Eagle. I designed the board to be single-sided but it does require 4 bridges.

I etched the circuit board using a laser printer, glossy photo paper, hydrogen peroxide and muriatic acid. Here are my etching notes in PDF format and this is a great website that further details the process.

Parts List:

Atmel ATMEGA8-16PI 1
74HC126N Quad Buffer 1
12 MHz Crystal HC49/US 1
28 pin IC socket 1
14 pin IC socket (optional) 1
Resistor Carbon Film 68 Ohm 1/4 Watt 10% 2
Resistor Carbon Film 270 Ohm 1/4 Watt 10% 1
Resistor Carbon Film 1K Ohm 1/4 Watt 10% 2
Resistor Carbon Film 10K Ohm 1/4 Watt 10% 5
Resistor Carbon Film 2K2 Ohm 1/4 Watt 10% 1
Resistor Carbon Film 22K Ohm 1/4 Watt 10% 1
Resistor Carbon Film 33K Ohm 1/4 Watt 10% 1
Ceramic Radial Capacitor 22pF 50V 5% 2
Ceramic Radial Capacitor .1uF 50V 10% 2
Electrolytic Radial Capacitor 4.7uF 16V 20% 1
3.6 Volt Low Power Zener Diode 2
5×2 Pin Gold Straight Header .100″ 1
2 x 1 Pin Gold Straight Header .100″ 3
Shunt .100″ 3
Red LED 1
USB Connector 1
Single-sided Copper Clad Board 1 oz. 3.5″ x 2.125″ 1
Altoids 50g Tin 1

Here is the pinout for the 10 pin ISP jack.

The AVR .hex code, USB .inf driver and other info is available from the AVR Doper Project site. Fuse Settings: CKSEL=1110 SUT=10 (Screenshot of Bascom Fuse Settings)

I have successfully tested the programmer with the 2008-11-27 firmware. I created a slightly modified version of the 2008_11_27 AVR Doper firmware to bypass the upgrade warning in AVR Studio. Here are my upgrading notes. The USB programmer can be used to upgrade itself if you have a spare ATMega8 chip.

Note (from AVR Doper website): Implementing a USB CDC device with AVR-USB violates some aspects of USB 1.1. CDC-Mode may therefore fail or be unreliable on some operating systems or computer hardware. Please look at the compatibility list included in the AVR-CDC project or test a simplified prototype on breadboard with your computer if you want to use CDC mode.

We recommend that you use AVR-Doper in HID mode instead, which has no such problem. This mode is supported by AVRDude. More information about interface modes and their relative advantages can be found in the project description.

AVRDude 5.3.1 and higher now supports the AVR Doper programmer. SinaProg is an excellent AVRDude GUI that also supports the AVR Doper.

Source: http://rototron.info/USBAVR/USBAVR.aspx Atmel AVR Programmer Circuit files alternative link :