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I bricked my Christmas lights

whizzy.org

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Re: I bricked my Christmas lights

#4

Post by Someone »

FTA:

> When we try and decrypt the on and off packets we get:

> 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00

> 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00

> 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00

> 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00

> 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00

> 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00

> Success! This is a lot more sensible. A fixed header, byte 5 switching between a 1 and a 0 for on and off, and a bunch of zeros.

I would guess that’s not a ‘fixed header’, but a length byte (“command is 5 bytes long”), a command (“TURN”) and an argument (zero or one), padded with zeroes to 16 bytes.

Re: I bricked my Christmas lights

#5

Post by willcooke »

Someone wrote: post #4

FTA: > When we try and decrypt the on and off packets we get: > 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00 > Success! This is a lot more sensible. A fixed header, by…

Oooh! Good spot. I will check other commands and see if that length idea works out. I think it could.

Re: I bricked my Christmas lights

#6

Post by willcooke »

CTOSian wrote: post #3
willcooke wrote: post #2

I was trying to automate my BLE connected Christmas lights but instead I created e-waste. Now you can too!

you can still use them as dummy/classic lights if you bypass the controller

+1

I can just swap the micro controller with something like an ESP8266 and run WLED.

Re: I bricked my Christmas lights

#7

Post by EvanAnderson »

Someone wrote: post #4

FTA: > When we try and decrypt the on and off packets we get: > 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 01 00 00 00 00 00 00 00 00 00 00 > 05 54 55 52 4E 00 00 00 00 00 00 00 00 00 00 00 > Success! This is a lot more sensible. A fixed header, by…

That "54 55 52 4E" jumped right out to my eye as the uppercase alphabet. Knowing that numbers start at 0x30, uppercase letters start at 0x41, and lowercase letters start at 0x61 makes alphanumeric patterns in hex dumps easy to spot.

That knowledge is good for short strings, but the canonical hexdump format is a the best way to look at packet and memory dumps.

Re: I bricked my Christmas lights

#8

Post by MarkusWandel »

Power supply failure? The WS281x things can go really bright, and, in bulk, suck an awful lot of current. A 12V, 3A power supply on a strip of 100 is just about enough to drive them all to full bright white, and dazzlingly bright it is. So I'd look for a blown fuse. The fact that the firmware only drives them to 31 out of a possible maximum brightness of 255 offers a clue.

Re: I bricked my Christmas lights

#9

Post by green-salt »

willcooke wrote: post #6
CTOSian wrote: post #3

Earlier quoted context omitted.

you can still use them as dummy/classic lights if you bypass the controller

+1 I can just swap the micro controller with something like an ESP8266 and run WLED.

I did this super similar (ESP32) with a set I got from walmart. Works great!

Re: I bricked my Christmas lights

#10

Post by wkjagt »

green-salt wrote: post #9
willcooke wrote: post #6

Earlier quoted context omitted.

+1 I can just swap the micro controller with something like an ESP8266 and run WLED.

I did this super similar (ESP32) with a set I got from walmart. Works great!

I find it amazing to think that your Christmas lights are now way more powerful than my first computer.
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