Monday, February 27, 2012

AT89S2051 base 8bit Bus Monitor

This is an AT89S2051 base 8bit bus monitoring utility. This module indicates bus values using hexadecimal numbering format and notify value changes by the beep. This utility is design to work with any 5V compatible TTL/CMOS - data/address buses.


This 8bit bus monitor requires 5V external power supply. In the idle mode this unit draws 15mA of current and in working mode (when inputs get change) this may raise up to 20mA – 30mA. Due to this low power profile, this system can also attach into the PSU of the "testing system".

This module is release as an open hardware project and it is covered with Creative Commons Attribution-ShareAlike 3.0 license. All the project related resources are available at Open Hardware Hub.

Tuesday, February 21, 2012

Kidogo : 8 channel USB Digital Signal Injector

Kidogo is 8 channel USB self powered digital signal injector. Kidogo system consists with Signal Editor and USB interface module. Kidogo Player is the Signal Editor of the Kidogo system and it can support up to 512 time slots (each range between 1ms to 1s) with 8 channels.



USB interface of the Kidogo system is based around Microchip’s PIC18F2550 microcontroller and generate 5V CMOS and TTL compatible outputs. Dimensions of current version of Kidogo USB interface is 53mm x 40mm (using standard through-hole components) and this can be reduce into more by using PCB layout based on SMD components.


Kidogo Player is design to work under the Microsoft Windows operating systems and it has following general features:

  • Save waveforms and settings as binary file (KDF file) or export waveform as a text file
  • Playback controls such as “Play to segment”, “Play from segment”, “Step back”, “Step next” and “Clear”
  • Shifting and rotating waveforms
  • Invert, Reset, Clocking and Binary Generator functions
  • Copy and Paste waveforms
  • Mute function to each individual channel
  • Launch without any installation or configuration (design to work as portable Windows application)

Kidogo is an open hardware project. All the project files (including PCB designs, source codes, etc.) are released under the Common Development and Distribution License (CDDL). Latest versions of Kidogo project content are available to download at Kidogo GitHub repository.

Wednesday, February 15, 2012

Yet another PIC development board

This is another configurable PIC microcontroller development board with E2PROM base storage and RS232 interface. Purpose of this development board is to emulate simple computation platform with storage, processing unit and control terminal.


This development board contain LM2576-ADJ base 3A switching voltage regulator (with external power terminals), E2PROM base storage (AT24C04) with 512words × 8bit space and standard RS232 serial interface.



All the peripherals of this development board can be isolated using onboard jumpers which include crystal oscillator, MCU reset line, E2PROM I2C interface and UART interface.

This development board supports most of the 40pin 5V PIC microcontrollers which include PIC18F4550, PIC18F452, PIC18F4620, PIC16F877, PIC16F887, etc.

Schematic diagram of this development board is available in Circuitbee with Creative Commons Attribution-ShareAlike 3.0 license.Link

Wednesday, February 1, 2012

Microscopic view of EEPROM IC

This is a Microscopic view of Fairchild Semiconductor's MBM27C64 E2PROM IC and ST Microelectronics M27C512 E2PROM IC.


M27C512


MBM27C64