Amazon Echo (1. Gen) Brain transplant (for use with HA Voice assist) - Page 1
Forum section: electronics / projects

author: Dani203
author_rank: Newbie
timestamp: November 08, 2023, 12:11:04 pm
content: Project Idea:Use an Amazon Echo (first Genereation) as a Home assistant Voice Assist device.What I already did:Research:iFixit have a great Teardown Article on their website, containing High Resolution Images of all PCBs and Chipnumbers.https://de.ifixit.com/Teardown/Amazon+Echo+Teardown/33953Home Assistant Documentation explains how the Voice Assist Integration works:https://www.home-assistant.io/voice_control/Aswell as the ESP-Home part of it:https://www.home-assistant.io/voice_control/thirteen-usd-voice-remote/ESPHome Documentation explains how Audio works:Speaker ->https://esphome.io/components/i2s_audio.html?highlight=audioMicrophone ->https://esphome.io/components/microphone/i2s_audio.html?highlight=audiobriandorey.com ->https://www.briandorey.com/post/echo-dot-3rd-gen-digging-deeperProbing:Since I am waiting for parts for an Initial Prototype (The DAC/Amp seams to be non functional), i spend the last two days probing the Echo with a Multimeter and comparing ICs to Datasheets. So far I have found some Data Pins and some Power/Ground, on the Top PCB (Mic ADCs, LEDs, Encoder). I used extremely blunt probes and I am looking into getting some sharper ones to do some further probing and investigating. I'm keeping you updated!Things I gathered:1) Broken Amazon Echo 1. Gen (Won't connect to the Internet, perfect candidate for this) -> ~20€ with shipping2) ESP32 Developement Board ->https://www.amazon.de/dp/B0C2CRRQCL-> ~9€/pc3) INMP441 Microhpone on Breakout board ->https://www.amazon.de/dp/B09G9LDQ48-> ~3,50€/pc4)MAX98357 Audio Chip on Breakout Board ->https://www.amazon.de/dp/B098R61GGG-> 8€/pc(sent back, seam to be broken)Some thoughts:1) I'd like to use as much of the Original Echo as possible, I'm just not sure how feasable the individual components would be.HousingI want to keep the Outside looks completely stock, so no visible mods to the exterior.Power BrickThe Echo comes with a 15V 21W external Power brick, which i'd like to use to keep the stock look.Speakers:Consisting of one Woofer and one tweeter, the should be more than adequate for What i want to use them for. They are connected to the Lower PCB.Lower PCBThe Echo has a Semicircular PCB at the botton that contains a Regulator (TPS53312), according to iFixit, it is likely an updated version of the TPS53311, which according to it's datasheet can be anywhere between 0,6 and 4,2V. I have measured some Pins of the Ribbon connector on the Mainboard to be 3.320V, so it is likely the supply Voltage coming from the Bottom PCB. I'd like to use that to power my ESP32.The PCB Also contains an Audicodec (TLV320DAC3203) and a 15W Stereo Class D amplifier (TPA3110D2). While it would be awesome to make use of them, it is probably only feasable if i can use both. Bypassing the Audiocodec, using my own DAC and still using the Amp is probably very annoying, probably Easier to Put the DAC/Amp in the Main PCB and connect the speakers there. Just need to figure out how to wire the speakers. Alternatively I could design a completely new Bottom PCB with a supported DAC, AMP and Step Down Regulation. It would probably be really hard to get a good fit of the barrel connector in the housing though.Upper Board:The Upper Board contains the following ICs:Texas Instruments SN74LVC74A Dual Positive-Edge-Triggered D-Type Flip-Flops -> Probably to interpret the Encoder on the board (?)Texas Instruments TLV320ADC3101 92dB SNR Low-Power Stereo ADC (x4) -> Converting the 7 S1053 0090 V6 Microphones from Analog to DigitalTexas Instruments LP55231 Programable 9-Output LED Driver (x4) -> Driving the Ring LEDs (12pc x 3ch), aswell as probably the Mute LED (+ maybe a second LED under the other button?)While it would be awesome to keep all of these componenets, i don't know if any of them would be feasable. Getting one of the Mics to work would be a great start, the Encoder is probably possible, LEDs might also be possible. But i wouldn't know where to start.What i need help with:You might (or might not) be surprised, that I am kind of a novice when it comes to Electronics. I have some very basic programming skills, some basic Electronics Knowledge. I've watched Daves Channel for many years, aswell as Louis Rossmann and others. This project is honestly way over my head, but i think with your help we might be able to make it work. The aim is not just for me to get this working, but to share all of our findings and make this easily replicatable for everone that is intrested. Of course that means, keeping all the code, PCB Files etc. open source. I feel like this project is so big, i don't even know everything I don't know yet, so I am eager to read your Input on this.1)Compatibility:How much of the mentioned Hardware could be brought to life with an ESP32 (ESP-Home)?2)Reverse Engeneering:How do we get Components to work?What ZIF connectors to we need to connect to the existing Flex Cables?What signal is where on the Flex cables?How do i design a PCB that fits in place of the Original Mainboard/Bottom Board/Top Board?Where do I start?....3)Equipment:I have a Multimeter, Linux and Windows PCs, basic soldering equipment/experience. I don't have access to a oscilloscope, microsoldering/hot air station, logic analyzers, etc.If nobody else is interested in my Idea or willing to help, I am afraid I'm never going to get it to work, let alone publish anything in a way thats sufficiently helpful to anyone. So if anyone is interested and willing to help, please share anything that you might think could be helpful or lead me in the right direction.

author: CountChocula
author_rank: Unknown
timestamp: November 08, 2023, 01:12:50 pm
content: I would probably only keep the parts that are “stock enough” that you can just reuse them: The chassis / cover, the speaker, and the microphone.Step 1, IMO should be to get those to work; once you have the ability to record and playback sound, you're pretty much done, hardware-wise, and the software becomes the pacing item.It looks like you already have most of the pieces you need to make this work; I don't know that you should bother trying to interface with the existing circuitry unless there's a compelling reason to.In terms of making your circuit fit in the existing case—first, this is a one-off, so perhaps it's not worth worrying about it; just find a way to fit all the various breakout boards so that they don't short and are secure, and it's probably good enough. In these cases, I find that hot glue is your friend.Even if you do want to design your own board, that's a problem for “future you,” who has already figured out how to make everything work. “Present you” has other things to worry about—CC

author: Dani203
author_rank: Newbie
timestamp: November 08, 2023, 04:18:16 pm
content: Hi,That would be the easy way, the way I normaly do stuffBut would it not be cool to develope a board, that the mainboard can easily be swapped by in order to completely convert a useles brick (or an Amazon Spy if you will) into a really cool smartspeaker. I might not be able to do it myself, but I am sure it must be possible...

author: CountChocula
author_rank: Unknown
timestamp: November 08, 2023, 06:36:30 pm
content: Quote from: Dani203 on November 08, 2023, 04:18:16 pmI'm sure it would… but you gotta start somewhere, and a PCB is really the last step once you know everything is working. Using these modules is convenient, because someone else has already figured out how to make the individual functions work. Once you have everything working using these building blocks, if you really want, you can just take their schematics (which are easily available through datasheets or Google) and combine them into a single PCB.