This is an USB Physical Hit Counter.This version requires one MCU to communicate between PC and 7-segments display driver.I decided using AVR and this is my first AVR project.The purpose of this project still same as previous version.Therefore,it used to count and display the total page hits on any website instead of using only general scripts such as PHP,Java,CGI etc.The host software no USB driver programming required.
The display I have used come from version 2 which it is MAX7219 and 7-segment x 8. MAX7219 requires only 3 I/O from MCU.ATtiny25 is the heart of this project.The firmware for this project written in AVR-GCC.This firmware modified from EasyLogger example which developed by Christian Starkjohann from Objective Development.Also,Christian Starkjohann developed an excellent USB firmware called AVR-USB which is a firmware-only implementation of a USB 1.1 compliant low-speed device for Atmel’s AVR microcontrollers.With this AVR-USB driver, it is easy to implement USB interface on AVR microcontroller project without dedicated USB hardware or no requires any USB to RS232 devices such as FT232.
From the circuit above this circuit requires at least 300mA,9-12V DC or AC external power supply for MAX7219 to avoid overloading on USB bus.The regulator(IC1) needs an appropriate heat sink.The IC3 use bus-powered.
0 comments:
Post a Comment