For sale, OTP PICAXE

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BeanieBots

Moderator
We've had a few posts recently along the lines of:-
"Can't program my PICAXE but it still runs the existing program OK."

Well, here's how to make an 08M OTP.
Write your program and download. (don't use pin0 for anything)
Connect pin0 (leg 7) to +12v for at least 10 secs but not much more.
Your program is now locked in safe and secure. It will be quite impossible to overrite it.
The down side.
Output 0 is always high and it runs a little warm.

For sale:-
PICAXE 08M with the following SECURE program:

Serout 2,(254,1)
pause 500
Main:
pulsout 0,10
w0=w0+1
serout 2,N2400,("Count= ",w0)
pause 200
goto main

Runs a little warm but no pulse on output 0.
Counts OK, great for testing AXE033. No worry about losing code.
Any offers accepted.

Seriously, DON'T TRY THIS AT HOME.
 
D

Dippy

Moderator
I just tried it Beanie.
My programme is so secure now that it is refusing to let me know what it's doing. It's either very, very security minded ... or broken.
A masterstroke.
 
B

BeanieBots

Moderator
Yes, I forgot to mention, it 'inhibits' ANY form of sertxd as well. Don't bother trying debug either. It's TOTALLY secure.
 
A

Andrew Cowan

Senior Member
I find breaking all the legs the PICAXE off also makes it harder for people to steal my valuable program.
 
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hippy

hippy

Technical Support
Staff member
BeanieBots said:
It's TOTALLY secure.
Click to expand...
But not necessarily unusable. You could try this ...

Code: 
                                    .------.
TX to PC   <------------------------| SO   |  A Normal
                     ___            |      |   PICAXE
RX from PC >----.---|___|---.-------| SI   |
               .|.          |       `------'
               | |          |
               |_|          |       .------.
               _|_          |       | FZ   |   Super
                            |       |      |  Protected
                            `------>| SI   |   PICAXE
                                    `------'
"FZ" : Frazzled :)
 
B

BeanieBots

Moderator
Not sure that would pass the verification process Hippy.
Too late now anyway. There was such high demand I've let it go.
Gave it to the nice man with yellow overalls who drives a big lorry. I've given him most of my 'specials' along with other houshold items I no longer have much need for.
As a final "security precaution", I cut all the legs off just in case it fell into the wrong project.
 
W

westaust55

Moderator
ylp88 said:
I couldn't help but remember the "release" of WOM (write-only) memory chips:

http://wei-lee.customer.netspace.net.au/wom.pdf

ylp88
Click to expand...
Ah the Signetics April Fools day joke from the US Electronics magazine April 1972 edition.

Dick Smith did a similar thing here in the Electronics Australia magazine around the same time.
Supposedly technology had allowed the creation of integrated circuits using special inks and printing technology.
The instructions were to cut out the special printed circuit from the magazine, soak in salt water and then solder your wires directly to the IC tabs.

Another Dick Smith April Fools day joke of the same era (1978) was to have a tug tow a barge into Sydney harbour with white sheeting and foam draped over a scaffold on the barge. In preparation in the days before, Dick had spent time advising the newspapers that he was going to tow an iceberg up from Antarctica as a demo as to how to obtain fresh water and overcome the water shortage in Australia.
 
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hax

New Member
I love how the bottom left graph of the datasheet has number of remaining pins vs number of socket insertions.
 
hippy

hippy

Technical Support
Staff member
The best 'April Fool' I remember was the Sandman Virus, code which would exercise particular internal chip wiring to excess, cause over-heating and failure of the chip itself, turning silicon into sand.

Quite amusing to think that software could damage hardware ... until that turned out to be a reality :)
 
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