NXP Semiconductors i.MX 8M User manual

NXPSemiconductors
Document Number: IMX8MAVSUG
User's Guide
Rev.
2
,
01/2019
User's Guide for NXP i.MX 8M Development
Kit for Amazon AVS
1.Introduction
The NXP i.MX 8M Development Kit for Amazon
Alexa Voice Service (AVS) enables its wide customer
base to easily integrate Alexa into their next generation
design based on i.MX processors. The development kit
consists of a 2-Mic array and the Pico i.MX 8M
development kit, both optimized to deliver a low cost
but flexible design to enable fast development to
production.
To enable customers to deliver a high-quality audio
experience we have partnered with DSP Concepts for
audio algorithms including echo cancellation, beam-
forming, and noise reduction to be delivered in
software. This results in a single chip solution, lowering
overall design cost, while ensuring customers to have
the support and expertise needed to deliver a high-
quality user experience in a short development time.
Contents
1. Introduction........................................................................1
2. What’s in the kit.................................................................2
3. Amazon account setup .......................................................4
4. Hardware setup ..................................................................9
5. Flash the board................................................................. 12
6. Install Alexa SDK ............................................................ 15
7. Running sample AVS App............................................... 26
8. Download MRM packages............................................... 29
9. Testing MRM................................................................... 34
10. Enable auto start of Alexa sample.................................. 44
11. Testing audio................................................................. 46
11.1. Testing audio with DSPC ..................................... 46
11.2. Testing Audio without DSPC (or before executing
setupAVS.sh) ..................................................................... 47
12. References ..................................................................... 48
12.1. Support ................................................................. 48
12.2. Key terms ............................................................. 48
12.3. Speaker references ................................................ 48
12.4. Ordering information and web links ..................... 48
© 2018 NXP B.V.

What’s in the kit
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This user’s guide provides step-by-step instructions for setting up the development kit and accessing and
testing Amazon AVS including account, hardware and software setup. When finished, you will have a
fully functioning prototype with Alexa built-in that uses the TechNexion Voice Hat 2-Mic Development
Kit as an audio front end, and the PICO-PI-IMX8M development board as the processor handling the
Alexa wake word recognition and interface to Amazon AVS.
The NXP i.MX 8M Development Kit for Amazon AVS is available on
https://www.amazon.com/dp/B07HBB1L5Kandhttps://shop.technexion.com/pico-pi-imx8m-
alexa.html.
2. What’s in the kit
Figure 1. NXP i.MX 8M development kit for Amazon AVS components
NOTE
Antistatic precautions are recommended for assembling the kit.

Amazon account setup
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Figure 2. NXP i.MX 8M Development Kit with connected TechNexion Hat
In addition to the kit, you will also require:
1. A windows PC with internet connection and a USB port.
2. USB 5 V power adaptor (or use an USB port capable of sourcing power from a PC). Some PC’s may
not provide enough power to the board and will re-boot. If this occurs please use a 5V charger
current instead.
3. Download the serial-to-USB drivers for serial debugging found here.
4. Multi-Room Music (MRM) feature enables music to be played and controlled across multiple,
compatible Alexa devices at the same time. In order to test MRM, you will need a second voice
kit or a MRM-enabled Alexa device.
NOTE ON SPEAKERS
The speakers provided in the kit are for initial prototyping only. For best
Acoustic Echo Cancellation (AEC) and Barge-in performance of the voice
input system, low distortion audio reproduction is important. High quality
speakers are recommended and for space restrained applications, single
transducer configurations perform better than multiple transducers with a
cross-over network.
Go to speaker references section for recommendations.

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Amazon account setup
3. Amazon account setup
To setup a developer account with Amazon, please perform the following steps.
1. Create a free developer account at developer.amazon.com. You can review the AVS Terms and
Agreements here. Create Alexa Voice Service (AVS) project, as shown in Figure 3.
Figure 3. Create Amazon account
2. Follow the steps as explained at https://github.com/alexa/avs-device-sdk/wiki/Create-Security-
Profile#product-information to register your product and create a device and security profile.
After entering in the Security Profile and Security Profile description sections, make sure to
select Other devices and platforms, as shown in Figure 4. Enter in the Client ID section and
select Generate ID.

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Amazon account setup
Figure 4. Generate client ID
NOTE
When prompted for the Client ID, make sure to use the Client ID from the
Other devices and platforms section.
3. On the Products page, click Manage and you can view your product details, as shown in Figure
5.
Figure 5. Product page
When done, the product profile is as shown in Figure 6 to Figure 9.

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Amazon account setup
Figure 6. Product Details –Information I
Figure 7. Product Details –Information II

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Amazon account setup
Figure 8. Product Details –Security Profile I

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Hardware setup
Figure 9. Product Details –Security Profile II

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Hardware setup
4. Hardware setup
This section will describe how to connect the Voice Hat board to the PICO-PI-IMX8M board.
1. Remove the jumpers on J11 on the Pico-Pi baseboard, as shown in Figure 10.
Figure 10. J11 on Pico-Pi baseboard
2. Change J2 jumpers to allow the board to boot the preloaded Linux image from eMMC, as shown
in Figure 11.
Figure 11. J2 on Pico-Pi baseboard
3. Verify the pin headers and jumper settings on the back of the audio hat, as shown in Figure 12
and Figure 13.

Hardware setup
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Figure 12. Back of Voice HAT (header settings)
Figure 13. Back of Voice HAT (switch settings from 1 to 8:10101010)
4. If using Wifi, connect the antennae to the antennae connector located on the top left of the SOM
5. Install the pin extenders on the Pico-Pi base board.
6. Plug the audio hat into the pin extenders on the Pico-Pi board, as shown in Figure 14
Figure 14. Audio hat plugged into the pico-pi board