Mike Jarabek's Projects
An 8051 based microcontroller kit
The IEEE Student branch at
McMaster University sells this kit to the third year students. This
kit comes un-assembled, the students must solder it together
themselves. The kit is used in several labs during the course
term. The four lab projects include: HP-2416 display interfacing,
matrix decoding, motor speed measurement, A/D and D/A.
My Power supply
This power supply uses an RS flip flop built from a 74LS00. It's no
mistake that there are no decopling capacitors on the supply rail near
the TTL ic. I wanted to make sure that if there was any noise, or a
short on the power supply, that the RS flip flop would trip off and
shut off the power. This device has saved me many times, after
hooking up power supplies wrong.
The XPando
This project uses 4 shift registers to create 32 digital outputs from
a single PC parallel port. This project comes in quite handy when you
need a bunch of digital outputs to control something on the breadboard.
Darkroom Timer
This is the darkroom timer to end all darkroom timers. It can
remember up to 8 different times, selectable from the left knob. The
right knob is a Bournes Gray coded rotary absolute shaft encoder. The
encoder delivers 7 bits of code for every rotation. This knob is used
to set the time delay. A remote button controls the starting and
stopping of the counter. In the first time setting, the enlarger lamp
is powered until the timer expires. Subsequent settings are for
timing the developer, rinse, fixer and rinse stages. For certain
stages, the safe light is automatically turned on. Inside is an Intel
8048, 2K of Rom, and a Lattice Isp1016 to do the display multiplexing
and driving.
A tarball with the Viewlogic Viewdraw schematics, Lattice Synario source
files, 8048 assembly language, and my own 8048 assembler is available here:
dtimer.tar.gz.
