NXP Semiconductors i.MX 8M Installation manual

i.MX Audio Board Hardware User's Guide
NXP Semiconductors Document identifier: IMXABHUG
User's Guide Rev. 0, March 2, 2021

Contents
Chapter 1 Introduction........................................................................................... 3
1.1 Board overview..........................................................................................................................3
1.2 Board contents.......................................................................................................................... 3
Chapter 2 Boards...................................................................................................5
2.1 Audio board............................................................................................................................... 5
2.2 Interposer board........................................................................................................................ 6
2.3 HDMI card................................................................................................................................. 7
2.4 Button board..............................................................................................................................8
2.5 8MIC-RPI-MX8 board (NOT INCLUDED IN THE AB2 KIT)...................................................... 8
2.6 IMX-MIPI-HDMI board (NOT INCLUDED IN THE AB2 KIT)..................................................... 9
Chapter 3 Assembly.............................................................................................10
3.1 Enclosure assembly................................................................................................................ 10
3.2 Board assembly.......................................................................................................................10
Chapter 4 Board setting....................................................................................... 12
4.1 Power setting...........................................................................................................................12
4.2 Board ID settings.....................................................................................................................12
4.3 Boot settings............................................................................................................................13
4.4 CPLD mode setting................................................................................................................. 15
4.5 S/PDIF settings........................................................................................................................40
Chapter 5 Updating software............................................................................... 42
5.1 SOM software..........................................................................................................................42
5.2 CPLD software........................................................................................................................ 42
5.3 HDMI card software.................................................................................................................44
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Chapter 1
Introduction
This document is the hardware User’s Guide for the i.MX Audio Board System based on the NXP’s i.MX 8M Series applications
processors. This system is fully supported by NXP Semiconductors. This manual includes system setup and configurations, and
provides detailed information on the usage of the i.MX Audio Board System from a hardware perspective.
1.1 Board overview
The i.MX Audio Board System is a platform designed to show the most commonly used audio features of the i.MX 8M Series
applications processor in a small and low cost package. The i.MX Audio Board System is a development system, which helps
developers get familiar with the audio and processor before investing a large amount of resources in more specific designs.
Table 1 lists the features of the i.MX Audio Board System.
Table 1. Board features
Processor NXP Applications Processor i.MX 8M Series SOM
DAC 3×8-CH DAC Line Out, support I2S, MSB justified, LSB justified, DSD and TDM. The sample
up to 768 KHz and bit depth up to 32 bits
ADC 1×2-CH ADC Line In, support I2S, MSB justified, DSD and TDM. The sample up to 768KHz
and bit depth up to 32 bits
S/PDIF I/O S/PDIF IO with RCA and TOSLINK connectors, TOSLINK supports up to 192 KHz
Ethernet Up to 1000 Mbps with RJ45 connector
Trigger DC 12.0 V 100mA output
MIPI-DSI DSI interface with Mini-SAS connector
USB Type-C connector for USB 3.0 or USB2.0 base on different SOM application
Debug Connector Micro USB for UART debug
Micro-SD Support TF card slot with detect pin
FPGA/CPLD LCMXO3LF-9400C-6BG484I, 484-balls with 383 I/O, 9400 LUTs, two PPLs. This chip is for
switching route of SAI signals to support multiple SAI configurations
I2C connector 8-pin dual-row Pin Header for I2C expansion
On Board Buttons ON/OFF, RESET buttons on the Audio Board
LED indicators Power status, UART on the Audio Board
Interposer Board Support i.MX 8M Nano and i.MX 8M Mini SOM
HDMI Card The default card is EP HDMI Card and the IC is EP92A7E. It supports HDMI 2.0 3-in 1-out
repeater with audio in/out, ARC/eARC and HDCP 1.4/2.3.
Button Board It is dedicated board on the front panel. It supports six user buttons, one ON/OFF button and
one status LED.
8MIC-RPI-MX8 Board Eight digital microphones board (Optional)
1.2 Board contents
The i.MX Audio Board System contains the following items:
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• i.MX Audio Board with metal enclosure
• Interposer Board
• EP HDMI Card
• Button Board
• 12 V 5A power brick
• SCREW-TY PE3 M3X5-5-S × 1
• BT/WiFi Antenna × 3
• Quick Start Guide
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Chapter 2
Boards
i.MX Audio Board System is an excellent, configurable and functional audio processing platform. It consists of Audio Board (or
MCIMX8M-AUD), Interposer Board, EP HDMI Card and Button Board. Audio Board is a base board, it is used to carry the various
sub-boards, audio devices and other integrated circuit devices. Interposer Board is an adapter for connection of i.MX 8M series
SOM and Audio board. EP HDMI Card is a HDMI signal switch, it can distribute HDMI audio and video signal from 3-RX port to
1-TX port. Button Board integrates 6 push buttons for customized use and 1 red LED for status indicator. Figure 1 shows the block
diagram for better understand the connection of whole system.
aaa-040660
EP92
A7E
HDMI
MODULE
i.MX 8M
Nano/Mini/Plus
SOM
SDIO1_C SDIO1
dedicated
I2C4
PCIE
_I2C3
HDMI
mFI
eARC
3.3 V 1.8 V
SDIO1_M
SPDT
JTAG JTAG SAI6/7(ENET) RGMII
I2C3
M.2
KEY E
AUDIO
DETECTION
I2C2
_I2C3
_I2C3
DAC3_I2S_DSD
DAC2_I2S_DSD
DAC1_I2S_DSD
ADC_I2C_DSD
1
2ch
SDIO_M
PCIE
I2S/SPI/UART/I2C
UART/SPI/PDM
I2S/UART
SAI5
SAI3
SAI1
Bypass Ethernet
GPIO/
UART/I2C/SPI
SDIO2_C
SDIO1_C
I2C2
I2S
RESET ON/OFF
USB type-C
BOOT
SDIO2
I2C2
SPDIF RX/TX
RCA + OPT
PHY1
RTL8211FDI
CG
BT
NXH3670
ADC
AK5552
2ch used
6ch reserved
REMOTE
DEBUG
MIPI-DSI
RJ45 w/
transformer
Micro AB
2 x 20 pins
RPI 2x20
I2C2
SDIO2_C SPDT
SD card
slot
JTAG
FT2232H Micro B
24ch
DAC
AK4458
8ch
DAC3
DAC2
DAC1
8 bit
Config switch
40.152
MHz
45.1584
MHz
484-balls
383 I/O
LCMXO3LF-
9400C-6BG484
Figure 1. System block diagram
2.1 Audio board
Audio board is a mixed signal base board, it has rich on-board functions and extensive interfaces. User can enable or disable
on-board DAC, ADC and more, or connect or disconnect HDMI card, digital microphone board, M.2 card and more base on
real application.
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There is an M.2 KEY-E connector on the audio board. It supports PCIe bus when using i.MX 8M Mini SOM. It
supports PCIe and SDIO bus when using i.MX 8M Plus. It is not suitable for i.MX 8M Nano SOM. NXP only verifies
the WiFi/BT module with PCIe or SDIO bus on this connector.
NOTE
There are three DACs on the audio board, each DAC has eight channels line out, the whole system has 24 channels line out with
RCA connectors. Channel configurations from 2-CH all the way up to 24-CH including 9.1.6, 7.1.4, 5.1.2, which are supported by
immersive decoders, such as Dolby ATMOS, DTS:X and MPEG-H. The on board DAC chips support digital audio data protocols
including I2S, MSB justified, LSB justified, DSD and TDM. Its maximum sample up to 768 KHz, The maximum bit depth up to 32
bits. User can distribute these line out signals freely base on the real application.
There is an ADC which supports two channels line in with RCA connectors. The ADC is a Δ-Σ A/D converter, it supports I2S, MSB
justified, DSD and TDM digital audio data protocols, the maximum sample rate up to 768 KHz and the maximum bit depth up to 32
bits. An audio detection circuit is constructed by separating components for ADC input. If a valid audio signal which greater than
-41.5 dBV appears on the red RCA connector, the detection circuit will respond to this. The analog audio signal will be amplified
and transmitted to the controller via optocoupler. Optocoupler outputs low logic when a valid audio signal appears. If this signal
is not used, system can ignore it directly.
Except for DAC and ADC codecs, this system also supports S/PDIF I/O, HDMI audio extraction and ARC/eARC, eight DMICs
and other audio related things. S/PDIF I/O with RCA connectors for coaxial communication and TOSLINK connectors for optical
communication. HDMI with type A connectors can realize audio extraction and ARC/eARC. DMIC with general 40 pins connector
for voice cases.
Refer to Figure 1 for understand audio board and Figure 2 for the real board.
aaa-040661
Button Board
Connector
USB Type-C
USB Debug
MICRO-SD
On/Off
Reset
SOM Connector
Interposer Board
Connector
8-DMIC
Connector
Power Mode
Jumper DC 12 V Jack ADC Parallel Jumper
S/PDIF Route
Jumper
M.2 Connector
I2C Connector
CPLD Download
Power Switch
DAC Parallel JumperCPLD Mode Switch
DAC 24-CH
ADC 2-CH
S/PDIF TX
S/PDIF RX
12 V Trigger
HDMI Card I/F
Ethernet
HDMI I/F
only 8M Plus
mini-SAS
Figure 2. Audio board
2.2 Interposer board
Interposer board is an adapter for connection of i.MX 8M SOM and audio board. This board perfectly solves the connection
between i.MX 8M Nano or i.MX 8M Mini SOM and audio board. This board makes audio board more extensible and compatible.
See Figure 3 for principle block diagram and the real board. The i.MX 8M Nano does not contain purple signals, i.e., MIPI-DSI,
PCIe, USB2, SAI1. For i.MX 8M Plus SOM can be plugged on the audio board directly and do not need interposer board.
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aaa-040662
UART3
INTERPOSER
BOARD
ECSPI2
I2C2
I2C3
I2C4
UART4
UART2
SD2
DSI
CSI
PCIE
USB1
USB2
BOOT
JTAG
CLK
MISC
SAI2
SAI1
2x50
SAI3
SAI5
SPDIF
GPIOs
1V8
3V3
5V0
ENET
REMOTE_DBG
ID#
NVCC NET
CPID_GPIOs
SPDIF
SAI2
MISC
CLK
SD2
ECSPI2
UART3
ENET
SAI5
SAI3
5V0
3V3
1V8
I2C4
I2C3
I2C2
SAl1
UART2
UART4
PCIE
CSI
DSI
JTAG
USB2
USB1
GPIOs
i.MX
AUDIO
BOARD
i.MX 8M
NANO AND
MINI
2x502x10
2x20
IO
EXP
I2C
SPOT
SPOT
2x50 2x50 2x50 2x50 2x50
16
4
10 bit10 bit
Figure 3. Interposer board block diagram and real board
2.3 HDMI card
HDMI board is an ecological design, every company or individual can join this ecosystem to design their own HDMI card base on
NXP's standard documentation. One HDMI card is provided by NXP, it has 3-CH receivers and 1-CH transmitter and supports
HDMI input and HDMI ARC/eARC. See Figure 4 for principle block diagram and the real board.
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5.0 V 1.25 V
3.3 V
1.27 V
MCLK
RX_BCLK
RX_FSYNC
RX_DATA[7:0]
TX_BCLK
TX
w/ eARC
RX1
RX2
RX3
TX_FSYNC
GPIOs
TX_DATA[7:0]
TX_DATA[11:8]
PWR_EN
IRQ_B
RESET_B
DCDCs
/LDOs
EP92A7E
3- in, 1-out
aaa-040663
Figure 4. HDMI card block diagram and real board
2.4 Button board
The button board is assembled on the front panel of metal enclosure. It has 6 push buttons, the functions of the 5 buttons can be
customized, 1 button is ON/OFF function that from SOM directly. The connection between the button board and the audio board
is realized by 10 pins cable. The button board is as shown in Figure 5.
Figure 5. Button board
2.5 8MIC-RPI-MX8 board (NOT INCLUDED IN THE AB2 KIT)
8MIC-RPI-MX8 is a digital mic phone board, there are eight microphones on the board, use this module for voice development
and so on. It is not in the Audio Board System Kit by default, but it can be found from 8MIC-RPI-MX8. Purchase it and plug directly
into the 40-pin expansion connector J1003 on the audio board. A reference picture is as shown in Figure 6.
aaa-040665
Figure 6. 8MIC-RPI-MX8 board
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2.6 IMX-MIPI-HDMI board (NOT INCLUDED IN THE AB2 KIT)
IMX-MIPI-HDMI is a MIPI-DSI to HDMI board. Use this board for MIPI-DSI to HDMI transformation, the HDMI monitor can be tied
to this interface for video display or other HMI cases. It is not in the Audio Board System Kit by default, but it can be found from
NXP website IMX-MIPI-HDMI. A reference picture is as shown in Figure 7.
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Figure 7. IMX-MIPI_HDMI board
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Chapter 3
Assembly
Audio Board System has a number of circuit boards as well as a metal enclosure. In the development and debugging, the assembly
of circuit board and enclosure should follow the corresponding steps, otherwise irreversible damage may occur.
3.1 Enclosure assembly
The enclosure consists of three parts, L-shaped bottom shell, U-shaped top shell and I-shaped rear panel. Generally, only need
to tear down the top shell for printed board assembly and electrical measurement and testing during development stage. A cross
screwdriver is required to remove the top shell. The upper casing can be removed after removing 28 screws that distributed on
the top and both sides of the top shell.
3.2 Board assembly
Audio board is a base board for other assemblable sub-boards. All installation and uninstallation should pay attention to electrical
connectivity. Do not install and uninstall these sub-boards frequently, because each connector has a limited plug-times.
3.2.1 Assembly of Interposer board
It is the hardest to install and uninstall interposer board, because there are three B2B connectors on the top of the board for
connection between SOM and interposer board, and there are six B2B connectors on the bottom of the board for connection
between audio board and interposer board.
Figure 8 illustrates the operation guide for this board.
1. Check all connectors on audio board.
2. Install interposer board into the base board.
3. Install the SOM board.
aaa-040667
Figure 8. Interposer board installation
There is also a wizard to uninstall the interposer board below. Recommend that use elbow tweezers, as shown in Figure 9, to
teardown interposer board and SOM board.
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