AcSiP EK-AI7931LD User manual

Version E
Doc No 912-13802
Date 2022/11/14
AcSiP Technology Corp
www.acsip.com.tw
EK-AI7931LD
User Guide
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Product Name
EK-AI7931LD
Version
E
Doc No
912-13802
Date
2022/11/14
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Document History
Date Revised Contents Revised By Version
2022/04/29
2022/08/25
2022/09/26
2022/10/20
2022/11/14
Initial Version
Add FCC Statement
Modify Hardware Features
Add EVK Schematic
Modify Hardware Features
Ivan
Ivan
Ivan
Ivan
Ivan
A
B
C
D
E
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INDEX
1. Introduction ......................................................................................4
1.1. General Description.........................................................................................................4
2. Get started with the HDK...................................................................5
2.1. Configuring the EK-AI7931LD...........................................................................................5
2.2. Installing the FTDI drivers on Microsoft Windows .........................................................6
3. Hardware Features ............................................................................8
3.1. Features Description.......................................................................................................8
4. Hardware Feature Configuration......................................................10
4.1. Microcontroller..............................................................................................................10
4.2. Power Supply ................................................................................................................10
4.3. Audio .............................................................................................................................13
4.4. Buttons ..........................................................................................................................14
4.5. RGB LED .........................................................................................................................14
4.6. SD Card ..........................................................................................................................15
4.7. Extension connectors.....................................................................................................16
5. Federal Communication Commission Interference Statement ..........24
6. EVK Schematic .................................................................................26
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Lists of Tables and Figures
Table 1 Jumper settings for system power input through USB connection.............................11
Table 2 Audio related function .................................................................................................13
Table 3 Buttons .........................................................................................................................14
Table 4 GPIO pin-out extension connector...............................................................................17
Table 5 GPIO pin multi-function definition ..............................................................................18
Figure 1. Front view of EK-AI7931LD ..........................................................................................4
Figure 2. Jumpers and connectors on the EK-AI7931LD ............................................................5
Figure 3. COM port associated with the EK-AI7931LD...............................................................7
Figure 4. Default power jumper plot ........................................................................................10
Figure 5. Power up the HDK using an AA or AAA Battery (J25) ..............................................12
Figure 6. Audio related function...............................................................................................13
Figure 7. RGB LED......................................................................................................................14
Figure 8. SD card slot rework....................................................................................................15
Figure 9. GPIO pin-out extension connectors...........................................................................16
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1. Introduction
1.1. General Description
AI7931LD is a highly integrated IoT module that features an ARM® Cortex-M33 application processor, a
low power 1x1 802.11a/b/g/n/ac/ax dual-band Wi-Fi subsystem, a Bluetooth v5.0 subsystem and a
Power Management Unit (PMU). The Wi-Fi subsystem and a Bluetooth v5.0 subsystem offer
feature-rich wireless connectivity at high standards, and deliver reliable, cost-effective throughput
from an extended distance. The AI7931LD is designed to support standard based features in the
areas of security, quality of service and international regulations, giving end users the greatest
performance any time and in any circumstance.
The AI7931LD is based on ARM® Cortex-M33 with floating point microcontroller (MCU) including
SRAM/ROM memory. The module also supports rich peripheral interfaces, including SDIO, SPI master, I2C,
I2S_IN, IR input, UART, AUXADC, PWM, and GPIOs.
These features are used to download and debug a project on EK-AI7931LD.
The front view of the EK-AI7931LD including AI7931LD module is shown in Figure 1.
Figure 1. Front view of EK-AI7931LD
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2. Get started with the HDK
Before commencing the application development, you need to configure the development platform.
2.1. Configuring the EK-AI7931LD
The top view of the EK-AI7931LD is shown in Figure 2
Figure 2. Jumpers and connectors on the EK-AI7931LD
The description of pins (Figure 2) and their functionality is provided below:
1) CON8 transfer USB interface to UART interface, can debug through UART, transmit, and receive a
signal form PC.
2) CON8 is a USB 5V power for EK-AI7931LD, or you can use external 5V power at J1.
3) Press SW1 to reset the system For SW2~SW5 more detail, please see “section 4.4”.
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4) For Wi-Fi and BT function AI7931LD module reserve a Wi-Fi + BT IPEX connector. Please connect
external antenna to transmit and receive RF signals.
5) U8 and U9 are on-board AMICs which can catch voice command.
6) U54/U56 are RGB LEDs and these RGB LED will be controlled by SPIM interface.
7) J28 and J87 support multifunction GPIO interface, for more detail please refer to “section 4.7”.
8) J10 and J11 are audio speaker pin header which can connect 8ohm/2W speaker to achieve voice
assistant function.
2.2. Installing the FTDI drivers on Microsoft Windows
To configure the EK-AI7931LD:
1) Connect the EK-AI7931LD CON8 to the computer using a micro-USB cable.
2) Check your PC is x86 or x64 system. And download and install FTDI Windows serial port driver from
Here. (The red block showed the download file at below figure)
3) If your OS is Windows7 or 10, please open Windows Control Panel then click System and enter
Device Manager.
4) In Device Manager, navigate to Ports (COM & LPT) (see Figure 3).
5) A new COM device should appear under Ports (COM & LPT) in Device Manager, as shown in Figure 3.
Note the COMx port number of the serial communication port, this information is needed to send
command and receive logs from the COM port.
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Due to the com port numbers (COMx) are different at different PC. As red block in Figure 3. showed,
means “CM33 UART”.
Figure 3. COM port associated with the EK-AI7931LD
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3. Hardware Features
This section provides the main supported features of the EK-AI7931LD The detailed description of the
features is provided in the upcoming sections
3.1. Features Description
3.1.1. Technology and Package
•AI7931LD LGA-104 module, 32mm X 32mm X 2.7mm (Typ.)
3.1.2. Power Management and Clock Source
•Integrates high efficiency power management unit with single 3.3V power supply input.
•Integrates 26MHz crystal clock with low power operation in idle mode.
•Integrates 32KHz crystal oscillator for low power sleep mode.
3.1.3. Platform
•ARM® Cortex-M33 MCU with FPU with up to 300MHz clock speed
•Embedded 1MB SRAM and 4MB PSRAM
•Embedded 16MB serial flash with eXecute In Place (XIP) and on-the-fly AES
•Supports Hardware crypto engines including AES, DES/3DES, SHA, ECC, TRNG for network
security
•Supports up to 22 General Purpose IOs, which are multiplexed with SDIO, SPI Master, UART, I2C,
I2S_IN, AUXADC, PWM and GPIO interfaces
•Supports 12 DMA channels.
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3.1.4. Wi-Fi
•IEEE 802.11 1T1R a/b/g/n/ac/ax 5GHz and 2.4GHz bands
•Supports 1x1 20MHz bandwidth, MCS0~8(256-QAM) in 2.4G/5GHz band
•Support uplink MU-OFDMA TX and downlink MU-OFDMA RX
•Support TX LDPC (Low-density parity check)
•Support RX STBC
•Wi-Fi security WFA WPA/WPA2/WPA3 personal
•QOS supports of WFA WMM
•Support CSI (Channel Signal Information)
3.1.5. Bluetooth
•BT5.0 2M_PHY / Long Range / Advertising Extension / SAM / CS#2 / High Duty Cycle
Non-Connectable ADV
•BT4.2 Link Layer Privacy / LE Secure Connection / LE Data Packet Length Extension / Link Layer
Extended Scanner Filter Policies
•BT4.1 Link Layer Topology / Secure Connection
•BT4.0 BLE only mode
•Up to 8 BLE links
•Packet loss concealment
•Channel quality driven data rate adaptation
•Channel assessment and WB RSSI for AFH
•Supports Bluetooth/Wi-Fi coexistence
3.1.6. Miscellaneous
•Embedded eFuse to store specific device information and RF calibration data.
•Advanced TDD mode Wi-Fi/Bluetooth coexistence scheme.
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4. Hardware Feature Configuration
4.1. Microcontroller
The AI7931LD features an ARM® Cortex-M33 processor, which is the most energy efficient ARM®
processor currently available. It supports the clock rates up to 200MHz when core power is 0.7V and
300MHz when core power is 0.8V. The MCU executes the Thump-2 instruction set for optimal
performance and code size, including hardware division, single cycle multiplication and bit-field
manipulation. The AI7931LD includes a Memory Protection Unit (MPU) in Cortex-M33 MCU to detect
unexpected memory access and provides other memory protection features. The AI7931LD also includes
FPU in Cortex-M33 MCU.
4.2. Power Supply
EK-AI7931LD supports two types of power supply.
1) Power up with a micro-USB connector.
An on-board switching regulator provides voltage of 3.3V for the EK-AI7931LD, if the power is supplied
from an on-board micro-USB connector CON8 (Figure 2). This supply can be isolated from the switching
regulator using the jumpers.
Note: that the jumpers J2, J3, J4, J5, J27 pin1 and pin2. JP1, JP2, JP5 pin1 and pin2 are required to be set
on. More details on the jumpers can be found in Table 1.
Figure 4. Default power jumper plot
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Table 1 Jumper settings for system power input through USB connection
Jumper Usage Comments
J1
External 5V power supply
Use external power source to supply 5V voltage to EK-AI7931LD
PCB. Pin 1 is 5V source. Pin2 is GND.
J2
DC-5V transfer to DC-3V3 current
source
J3
Current measurement (3V3) Measures the current flow in AI7931LD module.
J4
3V3 for EEPROM power EEPROM has no parts.
J5
3V3 for external components
J25
AVDD33_VRTC battery power supply
Use AA or AAA battery for RTC 3V3 power. Pin1 is positive
endpoint, Pin2 is GND.
J26 Current measurement in RTC mode RTC mode For AI7933CLD only.
J27 3V3 for SD_CARD power
JP1
Switch VCCIO_L to 3V3 power domain
or 1V8 power domain
Select pin 1 & 2, means VCCIO_L use 3V3 power domain
Select pin 2 & 3, means VCCIO_L use 1V8 power domain
JP2
Switch VCCIO to 3V3 power domain
or
1V8 power domain
Select pin 1 & 2, means VCCIO use 3V3 power domain
Select pin 2 & 3, means VCCIO use 1V8 power domain
Caution: The flash of AI7931LD default using3V3 power domain, if
you want to change VCCIO to 1V8 power domain please rework
flash to 1V8 power domain flash (eq. W25Q128JWPIQ)
JP3
Switch 1V8 VCCIO from internal
PHYLDOor external LDO
Select pin 2 & 3, means 1V8 VCCIO from internal PHYLDO
Select pin 1 & 2, means 1V8 VCCIO from external Buck
component
JP5
Switch RTC 3V3 from DC-3V3 or
AVDD33_VRTC
Select pin 1 & 2, means RTC_3V3 use DC-3V3
Select pin 2 & 3, means RTC_3V3 use
AVDD33_VRTC
JP7
Switch SD Card to 3V3 power domain
or
1V8 power domain
Select pin 1 & 2, means SD_CARD power use 1V8 power domain
Select pin 2 & 3, means SD_CARD power use 3V3 power domain
JP9
Switch EEPROM(NC) to 3V3 power
domain or
1V8 power domain
Select pin 1 & 2, means EEPROM power use 3V3 power domain
Select pin 2 & 3, means EEPROM power use 1V8 power domain
J88
5V for (U10) Audio AMP power Pin 1 is EXUSB_5V
J89
5V for (U10) Audio AMP using Pin 1 is EXUSB_5V
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2) Power up using an AA or AAA battery.
Connect an external AA or AAA battery to battery pin header (J25) to supply power to the system, as
shown in Figure 5. Please note that remove jumper J2 and plug in jumper J26. Jumper JP5 can be removed.
Figure 5. Power up the HDK using an AA or AAA Battery (J25)
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4.3. Audio
The EK-AI7931LD has on-board audio connector associated with different functionalities of the board.
The detail of audio related function can refer to Table 2.
Table 2 Audio related function
item Detail
J8 3.5mm audio jack for external active speaker.
J6 Audio-Left_P switch , Pin(3,2,1) Pin define (Amp_L_in_P , Module_audio_out_L, Audio jack_L_in)
Select pin 2 & 1, The audio is output by audio jack. Select pin 3 & 2, The audio is output by speaker (J10)
J24 Audio-Right_P switch, Pin(3,2,1) Pin define (Audio jack_R_in , Module_audio_out_R ,Amp_R_in_P)
Select pin 3 & 2, The audio is output by audio jack. Select pin 2 & 1, The audio is output by speaker (J11)
J85 Audio-Left_N , Pin(1,2) Pin define (Audio_L_N,GND)
J86 Audio-Right_N, Pin(1,2) Pin define (GND, Audio_R_N)
J10 Audio header for left speaker
J11 Audio header for right speaker
U8 AMIC for left channel (the microphone hole is set at back side of EK-AI7931LD)
U9 AMIC for right channel (the microphone hole is set at back side of EK-AI7931LD)
SW2 Audio volume up button
SW3 Audio volume down button
Figure 6. Audio related function
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4.4. Buttons
The EK-AI7931LD is equipped with buttons with the following functionality.
The push buttons are shown in Figure 2 The detail of buttons can refer to Table 3.
Table 3 Buttons
Button Name Detail
SW1 SYSRST Press SW1 to restart the EK-AI7931LD
SW2 Vol+ Audio volume up button
SW3 Vol- Audio volume down button
SW4 RTC_EINT For AI7933CLD only
SW5 Force DL mode Press SW5 to trigger strapping mode (download mode…)
4.5. RGB LED
As Figure7. showed, the EK-AI7931LD has on-board RGB LEDs (U54/U56) which be controlled by SPIM
interface. Please note that ensure jumper J79 and J80 are connected before using RGB LED function If
you want to cascade more RGB LED, you can connect to J78
Figure 7. RGB LED
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4.6. SD Card
The EK-AI7931LD reserve a SD card slot to provide user to save data into a SD card. And note that there
are some registers which placed need to be reworked before using SD card. Please refer to figure.8 and
switch R756 to R757; switch R745 to R751; switch R744 to R750; switch R746 to R747; switch R748 to
R749; switch R754 to R755; switch R752 to R753.
Figure 8. SD card slot rework
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4.7. Extension connectors
The EK-AI7931LD provides similar pin-out extension connectors for various sensor and device
connectivity, as shown in Figure.9 and described in Table 4.
The board has 22 GPIOs multiplexed with other interfaces. Depending on the use case, user can
configure each I/O functionality.
Note: GPIO-12 & GPIO-C_12 are the same circuit.
GPIO-13 & GPIO-C_13 are the same circuit.
GPIO-15 & GPIO-C_15 are the same circuit.
Figure 9. GPIO pin-out extension connectors
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Table 4 GPIO pin-out extension connector
Signal Name Connector Pin Number Signal Name Connector Pin Number
GPIO_0 Reserve for flash GPIO_14 J87 - 9
GPIO_1 Reserve for flash GPIO_15 J87 - 11
GPIO_2 Reserve for flash GPIO_17 J87 - 13
GPIO_3 Reserve for flash GPIO_18 J87 - 15
GPIO_4 Reserve for flash GPIO_19 J87 - 17 Reserve for Arduino:I2C1_SDA
GPIO_5 Reserve for flash GPIO_20 J87 - 19 Reserve for Arduino:I2C1_SCL
GPIO_6 J28 - 2 Reserve for Arduino:SPI0_CSK GPIO_21 J87 - 21
GPIO_7 J28 - 4 Reserve for Arduino:SPI0_CSN GPIO_22 J87 - 23
GPIO_8 J28 - 6 Reserve for Arduino:SPI0_MISO GPIO_23 J87 - 25
GPIO_9 J28 - 8 Reserve for Arduino:SPI0_MOSI GPIO_24 J87 - 12
GPIO_10 J28 - 10 GPIO_42 J28 - 30 Reserve for Arduino:UART1_RX
GPIO_11 J28 - 12 GPIO_44 J28 - 28 Reserve for Arduino:UART1_TX
GPIO_12 J87 - 5 GPIO_48 J87 - 6 Reserve for CM33 UART
GPIO_13 J87 - 7 GPIO_50 J87 - 8 Reserve for CM33 UART
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Table 5 GPIO pin multi-function definition
IO Name
CR Value
Default*
Name Dir
Default
Description
Dir PU/PD
PAD_SYSRST_B NA PAD_SYSRST_B PU Chip hardware fundamental reset pin
SDIO_CLK
0000 GPIO[6] I/O
I PD
GPIO 6
0001* SDIO_CLK I SDIO Clock
0010 MSDC0_CLK O MSDC Clock
0011 SPIM0_SCK O SPI0 (Master) Clock
0100 CM33_GPIO_EINT0 I CM33 EINT0
0101 DEBUG_0 O Debug Signal 0
0110 ANT_SEL0 O Antenna Select 0
0111 RSVD I RSVD
SDIO_CMD
0000 GPIO[7] I/O
I PU
GPIO 7
0001* SDIO_CMD I/O SDIO CMD
0010 MSDC0_CMD I/O MSDC CMD
0011 SPIM0_CS_N O SPI0 (Master) Chip Select
0100 CM33_GPIO_EINT1 I CM33 EINT1
0101 DEBUG_1 O Debug Signal 1
0110 ANT_SEL1 O Antenna Select 1
0111 RSVD I RSVD
SDIO_DAT0
0000 GPIO[8] I/O
I PU
GPIO 8
0001* SDIO_DAT0 O SDIO Data[0]
0010 MSDC0_DAT0 I/O MSDC0 Data[0]
0011 SPIM0_MISO I SPI0 (Master) Input
0100 UART0_RTS O UART0 RTS
0101 DEBUG_2 O Debug Signal 2
0110 ANT_SEL2 O Antenna Select 2
0111 CM33_GPIO_EINT0 I CM33 EINT0
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IO Name
CR Value
Default*
Name Dir
Default
Description
Dir PU/PD
SDIO_DAT1
0000 GPIO[9] I/O
I PU
GPIO9
0001* SDIO_DAT1 I/O SDIO Data[1]
0010
MSDC0_DAT1
I/O
MSDC0 Data[1]
0011 SPIM0_MOSI O SPI0 (Master) Output
0100
UART0_CTS
I
UART0 CTS
0101 DEBUG_3 O Debug Signal 3
0110
ANT_SEL3
O
Antenna Select 3
0111 CM33_GPIO_EINT1 I CM33 EINT1
SDIO_DAT2
0000 GPIO[10] I/O
I PU
GPIO 10
0001* SDIO_DAT2 I/O SDIO Data[2]
0010 MSDC0_DAT2 I/O MSDC0 Data[2]
0011 I2SIN_DAT0 I I2S In Data0
0100 UART0_RX I UART0 RX
0101 DEBUG_4 O Debug Signal 4
0110 I2C0_SCL O I2C0 Clock
0111 CM33_GPIO_EINT2 I CM33 EINT2
SDIO_DAT3
0000 GPIO[11] I/O
I PU
GPIO 11
0001* SDIO_DAT3 I/O SDIO Data[3]
0010 MSDC0_DAT3 I/O MSDC Data[3]
0011 I2SO_DAT0 O I2SO Data
0100 UART0_TX O UART0 TX
0101 DEBUG_5 O Debug Signal 5
0110 I2C0_SDA I/O I2C0 Data
0111 CM33_GPIO_EINT3 I CM33 EINT3
GPIO_B_0
0000 GPIO[12] I/O
O PU
GPIO 12
0001* CONN_BGF_UART0_TXD O BT General UART TX
0010 MSDC0_RST O MSDC0 Reset
0011 CONN_BT_TXD O BT Debug UART TX
0100 WIFI_TXD O Wi-Fi Debug UART TX
0101 DEBUG_6 O Debug Signal 6
0110 ANT_SEL3 O Antenna Select 3
0111 CM33_GPIO_EINT4 I CM33 EINT4
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