Om den Sound-Brick från 76429 (Talking Sorting Hat)

[narwo]

Har köpt set

76429 (Brickset)

så jag kan set om det finns molnighet att byte ut ljud.

Spoiler alert: nej, det gå inte

Writing in English, so I can explain better...

First, I opened the 2 screws which Lego has kindly provided for changing the batteries.

Inside are 3 LR44 batteries, which provides a total of 4.5v. They can easily be purchased at Kjell/Clas Ohlson etc. Thumbs up to Lego for easily replaceable batteries!

Then there is a black box, which will be the speaker. This will be connected to a tiny green PCB which will have the electronics that stores the sound clips and plays them when the white button is pressed.

Now it's time to remove things....


With a little kind words and some plastic tools, the PCB is free. It's connected by 2 wires to the speaker and has very little electronics. From the right...there is a metal spring to touch the battery. Then a small push button which hides behind the white rubber button you press to make the sounds. Next to that is a chip with 8 legs, this package is called SOP-8 and is a very common size for simple chips. There normally are markings on chips with a part-id, but no...nothing on this one

There are also some round gold test points, which will be used the factory to test and write the sounds to the chip.



I've looked at the PCB and chip under a microscope, but I didn't find anything new.

On the board is printed (silkscreen) the letters OTP HOW. This probably means that it's a "one-time programmable" chip...for HOW which may mean HOgWarts?

OTP is bad for us hackers, it means we can't change the sounds.

So that's about it I'm afraid...I'm quite certain it's not very hackable without changing the PCB or chip.

However...I won't leave it at that...I want to know more...
A quick search has shown me the chip WTH080, a "toy mp3 voice chip"...sounds perfect. I'll investigate to see if this is likely the one they used. You can read about this chip on this datasheet.

I'll update this thread when I find out more...

[MrUzagi]

Spännande. Det setet står på min inköpslista, så det ska bli intressant att se om du får fram mer om ljudchipet.

[narwo]

To find the right chip, I need to know what some of the pins do, luckily this is what I do for my job!

Pin1 is always the one marked on the chip...so that'll be top-left.

1. ?
2. ?
3. Connected to SW1, known as "Trigger"...probably will say "Triggers random sound" in the datasheet.
4. ?

5. 0v/GND/VSS
6. 5v/VDD
7. PWM - (Audio)
8. PWM + (Audio)

[narwo]

Forgot to say, C1 is likely a 100nF capacitor...which is used to make the power supply smoother.

On the back it has the PCB and SCH IDs...these are just the design IDs of the Schematic and PCB.

W400 << no idea what this means...

[robinnilsson403]

Spännande att följa! Jag bygger ytmonterat på jobbet.

[Godtfred]

De 4 kretsar i kapsel SO8 som finns på sidan du pekade på stämmer bara nästan med pinouten i modulen. Men inte riktigt. Matningen och utgångarna är omkastade lite annorlunda. Kanske finns fler kretsar i den familjen? Pinnarna 1-4 har serieinterface för programmering. Jag skulle försöka prata med kretsen den vägen... Men lyckas inte ladda ner mer detaljerad spec som visar hur något av serieinterfacen och hur registren ser ut.

Nu har jag ingen sådan modul, men kanske ska köpa en för att prova. Har öppnat många kretsar i plastkapsel för att undersöka kislet med mikroskop, står säkert modellbeteckning på layouten någonstans.

[narwo]

Jag är helt säkert att det är ett one-time-programmable IC, så jag tänkt att fokusera att identifiera IC:n så jag kan köpa fler och göra ett clone av kretskortet. Men...jag vet att det är inte lätt att byte ut ljudet...det var mitt första mål.