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Welcome to my little shop of art and stuff where everything is free for non-commercial use. In case you find something useful proper credit will be greatly appreciated. I am an occasional hobbyist in the field of drawing/painting and somewhat more active in electronics. Both aspects are presented in the following pages.

The Art Gallery features experiments using ballpoint pens, dry media and some oil paint.

The Electric Circuits page lists a number of excerpts, mostly elementary and others partly drawn from earlier work in the field of analog electronics that overall might be of some educational value. 

The DemUino machines are microcontroller based computers using the arduino/sanguino hardware libraries. The heart of each system is a simple command interpreter that also supports mathematical expressions in RPN. I had to remove a few of the different implementations in order to make it more practical to update the posted firmware. Use either IDE 1.6.5 or IDE 1.6.12 as suggested to compile the source code. In general 1.6.5 produces a larger flash image.


Nick Gammon's High-voltage programmer for AVR chips
Recover your bricked atmega328p by changing the fuses.
Note:
If you don't have available a p-mosfet for the RESET circuit you can use a PNP BJT such as the complementary of 2N3904 - the 2N3906 - driven with a 10K or smaller resistor from the collector of 2N3904 to its base. The small resistor will ensure saturation of the CE junction; also, you will need a load of a few KOhms (I used 2.2K - use 3.3K,4.7K etc) from its collector to GND. Its collector also connects to the RESET pin of the target.
Instead of the 2N3904-6, I used a pair of BC546-BC556 BJT transistors.




 DemCalc 
ver 5.0 

STACK BASED RPN
SCIENTIFIC CALCULATOR



  • 5 key maps
  • BigNumber & avr-libc
  • Scientific/programmer
  • Stack based X,Y, Z & T registers.
  • Standard/scientific notation
  • Transfer Function  s/z/real.
  • User defined system settings.   
  • Clock display.
  • Low battery drain <2mA min. 
  • Auto shutdown less than 1uA


 MusicPlayer
version 3.4

  • Uses a single atmega328p and an LM386 amplifier
  • Plays 8bit PCM uncompressed raw music data
  • 8-bit R-2R DAC, 4 navigation keys, 8x2 LCD, 0.5W amp
  • 2xAAA batteries or USB operation and charging
  • 8, 11, 16 and 22 KSPS sample rates
  • Records from external source at 8, 11 and 16KSPS
  • DDS for low frequency audio tones
PDF

BINARY & ALL 



DemUino Portable v1.54 
main v1.40 - keyboard v1.68
4x11 - 2+1 keypads



Use IDE 1.6.5 for compiling.

SD card suppor.
 Includes floating point math, 
convolution, DFT, z and s tranforms
version 2.997
with built-in
MUSIC PLAYER


     PDF

      BINARIES & ALL


Use IDE 1.6.12 for compiling.

PS/2 keyboard + SD. 
Includes direct floating point math calculations, 
DFT, convolution, z and s transforms, 
8-bit raw music file playback.


If you have comments or questions you can either contact me at biromaster@yahoo.com or if you have a google account you can first sign in and then leave a comment at the bottom of the corresponding page.

Thanks for visiting and I hope you enjoy your stay.