Electronics Forum / Basics / February 2007

I have no idea - your tinyurls want me to register. Why not download the
pages and slap them up on your website?

Good Luck,
Rich

Sorry, your links don't seem to work now.

That is a PIC, you can get them many places.  The issue will be getting it
programmed.  I can probably help you out since the HEX file is available.  I
don't see any source code though.  :-(

These are pretty generic, so any will do fine.  It just has to be made for
the right frequency (56kHz aparently).

Any 1/4W or 1/8W carbon-comp should do.

You want a ceramice disc for C1 and an electrolytic for C2.  Since the
voltage in the circuit is so low, almost any will do.

I looked at the schematic, and there are some things I wonder about.  Most
IR receivers have an open-collector output (meaning they can't supply a
positive drive voltage on their own).  I would expect to see an external
pull-up resistor, I assume the creator is using the "weak" pull-ups built
into the PIC.  This may work ok, but may also be prone to noise pickup
especially if the wires are longish.

Too bad he didn't seem to provide the source, or I could have easily
converted it to run on a smaller, cheaper PIC that I happen to have on hand.

Hi Jim,

The Tiny URL's that you have posted, take us to the RS website, but it tells
me that the session has timed out!  You would be much better off posting the
RS order codes for us to look at.

Cheers,

Tim

For C2 http://www.maplin.co.uk/search.aspx?MenuNo=56055&MenuName=ELECTROLYTICS&worldid=
-2&FromMenu=y&doy=22m2
code AT05F

C1 is fine.

Diode is fine (code QL80B)

The search page for RS components was gone and a quick search didn't find
an IR receiver module that can use. Google for "IR receiver module" and
see what you can come up with.

Again the search page had disappeared, but they do have the chip, RS Stock no. 467-2255.
The problem here is that you will need some way to progam the HEX file into the chip.

I don't what Rich Grise was talking about, nothing required me to register.

Mike

"The scientist is possessed by the sense of universal
causation...His religious feeling takes the form of
rapturous amazement at the harmony of natural law,
which reveals the intelligence of such superiority
that, compared with it, systematic thinking and acting
of human beings is an utterly insignificant reflection."
Albert Einstein (theoretical physicist)

If your goal is the learning experience, go for it.
If you only care about remoting the thing, you could
easily hack an old R/C toy car.  You can still experiment
and learn with the project as you outlined it, and
you'll already be able to use xbox remotely while you
play with the project. You'll have the hacked remote
done in an afternoon with two relays, 4 diodes and a
power supply.  Conceptually:

 +V -------------+-----+
                 |     |       ---o--> To xbox
               [RLY1] [D2]     ^--o-->
                 |     |a
   A >-----|<----+-----+---o---
           D1              o--^ RLY1 -1 n/o contact
                           |
   B >----->|----+-----+   o---
           D3    |     |      ^ RLY2 n/c contact
               [RLY2] [D4] o--'
                 |     |a  |
 Gnd ------------+-----+---+

Points A and B are the wires in the R/C car
that normally connect to the motor.
Run the car forward & RLY1 energizes and
stays energyzed through its own open point
and the closed point on RLY2. Run the car
backwards, and RLY2 energizes, dropping
out RLY1.  The RLY1-2 contact set goes to
the xbox.

Ed