Tea O Matic is a little helper to pull out tea colander, egg or sac, when the tea brewing
time is over. Controled by a computer program it finishes tea brewing just in time - automatically.
Unfortunately its not posible to have always a eye for my brewing tea.
Sometimes the telephone rings, sometimes somebody has his problems with
something i don't want to think about ... or simply the complete server
farm blinks red in my network monitoring tool. In the past a lot of forgotten
teas where inedible :-(
The first solution was the wmTea
It creates a little icon with a tea pot, a clock and a brewing time end signal.
But the problem was: How do You pull out the tea colander by hand when You're in
trouble with some broken network connections ?!
The idear to build a little electrical actuator was very old. In the past i thought
on new parts, but with the "Mach flott den Schrott" (german: means: refloat the scrap )
competition of the german computer magazine Ct'
(the goal was to build something complete new from computer scrap) i started to think about
using broken things out of computers.
The result is an actutator build from a broken
CDROM drive (it wasn't possible anymore to read CDs with), an old AT PC-power supply and
a lot of other computer scrap. The controler was implemented with a PIC16F628 from Microchip
and a MAX 232 driver to handle the RS232 interface for communication with wmTea.
I removed the CDROM drive's Laser and the electronic for CD reading (that speeds up initializing the drive),
- simply the loader mechanics and the electronic for the loader button & motor where still present after modification.
The power supply was an old AT one without any use in modern computers
- so the PIC controller, the MAX 232 the CDROM motor and every left electronic
was supplied by this power supply. Additionaly the supply was used as stand.
The controler unit is soldert on a single sided circuit board.
Next to the PIC and MAX 232 is also a optocoupler, some indicator lights and 2 function
buttons. Position of coleander holder is taken over two magnet field detechtion HAL sensors.The communication is like the AT instructionset also known
from a lot of MoDem devices. Implemented is the logic with some PIC-assembler commands.
The RS232 terminal command set:
|ATDT||start brewing sequence - colander holder goes down||X
|ATZ||end brewing sequence - with shaking||X
|ATXZ||end bewing sequence - without shaking ||X
|ATRS n||read out sensors||
|ATWA n||set an actor n||
|ATSTA||write out status to RS232||X
|ATV||write out complete startup message||X