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Duo S

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Milk-V Duo S is an upgraded model of Duo, featuring an upgraded SG2000 main controller with a larger 512MB memory and expanded IO capabilities. It integrates wireless capabilities with WI-FI 6/BT 5, and comes equipped with a USB 2.0 HOST interface and a 100Mbps Ethernet port for user convenience. Supporting dual cameras (2x MIPI CSI 2-lane) and MIPI video output (MIPI DSI 4-lane), it allows for versatile applications. The device also supports switching between RISC-V and ARM boot through a switch. With enhanced functionality, Duo S is better suited for a variety of scenarios with more complex project development requirements.

Introduction of SG2000

SG2000 is a high-performance, low-power chip designed for various product fields such as edge intelligent surveillance IP cameras, local facial recognition attendance machines, and smart home devices. It integrates H.264/H.265 video compression and decoding and ISP capabilities. It supports various image enhancement and correction algorithms like HDR wide dynamic range, 3D noise reduction, defogging, and lens distortion correction, providing customers with professional-grade video image quality.

The chip also integrates an in-house TPU, delivering approximately 0.5TOPS of computing power under INT8 operations. The specially designed TPU scheduling engine efficiently provides high-bandwidth data flow for tensor processing unit cores. It also offers users a powerful deep learning model compiler and software SDK development kit. Mainstream deep learning frameworks such as Caffe, Pytorch, ONNX, MXNet, and TensorFlow (Lite) can be easily ported to this platform.

SG2000 Public Preliminary Datasheet

We have open sourced the Public Preliminary Datasheet and TRM of SG2000 to GitHub. please check it out.

Buy the SG2000 Chips

Milk-V is the Authorised Global Distributor of the SG2002 chips. You can buy samples of the SG2002 chip from our distributor online store directly. For volume order, please contact Milk-V Sales Team for the qoutation.

DuoS GPIO Pinout

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GPIO pin mapping

GROUPADDRPORTCHIPNUMNAMESTART
gpio0gpio@03020000portagpiochip0480-511XGPIOA480 - XGPIOA[0]
gpio1gpio@03021000portbgpiochip1448-479XGPIOB448 - XGPIOB[0]
gpio2gpio@03022000portcgpiochip2416-447XGPIOC416 - XGPIOC[0]
gpio3gpio@03023000portdgpiochip3384-415
gpio4gpio@05021000portegpiochip4352-383PWR_GPIO352 - PWR_GPIO[0]

Header J3

GPIO on Header J3 use 3.3V logic levels.

SPIPWMI2CUARTNUMSG2000NAMEPINPINNAMESG2000NUMUARTPWMSPIJTAG
3V3
1
2
VSYS(5V)
PWM3I2C4_SCL468XGPIOB[20]B20
3
4
VSYS(5V)
I2C4_SDA469XGPIOB[21]B21
5
6
GND
I2C1_SCL466XGPIOB[18]B18
7
8
A16XGPIOA[16]496UART0_TX/UART1_TXPWM4
GND*
9
10
A17XGPIOA[17]497UART0_RX/UART1_RXPWM5
PWM1I2C1_SDAUART2_TX459XGPIOB[11]B11
11
12
B19XGPIOB[19]467UART2_TXPWM2
PWM2I2C1_SCLUART2_RX460XGPIOB[12]B12
13
14
GND
UART2_RX470XGPIOB[22]B22
15
16
A20XGPIOA[20]500JTAG_TRST
3V3
17
18
A19XGPIOA[19]499UART1_TX/UART1_RTSPWM7JTAG_TMS
SPI3_SDOPWM3I2C2_SCL461XGPIOB[13]B13
19
20
GND
SPI3_SDII2C2_SDA462XGPIOB[14]B14
21
22
A18XGPIOA[18]498UART1_RX/UART1_CTSPWM6JTAG_TCK
SPI3_SCKUART2_TX463XGPIOB[15]B15
23
24
B16XGPIOB[16]464UART2_RXSPI3_CS
GND
25
26
A28XGPIOA[28]508UART2_TX/UART1_TX

GND*: Pin 9 is a low-level GPIO in the V1.1 version of the hardware, and is GND in the V1.2 version and later.

NOTE: The I2C on the CSI camera connector J2 is I2C2, so when using the CSI camera on J2, I2C2 in the J3 pin header is not available.

Header J4

GPIO on Header J4 use 1.8V logic levels.

PWMI2CUARTMIPI DSINUMSG2000NAMEPINPINNAMESG2000NUMMIPI DSI
VSYS(5V)
52
51
AUDIO_OUT_R
PWM12I2C4_SCLUART3_TX499XGPIOB[1]B1
50
49
AUDIO_OUT_L
PWM13I2C4_SDAUART3_RX450XGPIOB[2]B2
48
47
AUDIO_IN_R
451XGPIOB[3]B3
46
45
AUDIO_IN_L
PWM10I2C2_SDALCD_RST354PWR_GPIO[2]E2
44
43
3V3
PWM9I2C2_SCLUART2_RXLCD_PWR_CT353PWR_GPIO[1]E1
42
41
C18XGPIOC[18]434MIPI_TX_3N
PWM8UART2_TXLCD_PWM352PWR_GPIO[0]E0
40
39
C19XGPIOC[19]435MIPI_TX_3P
GND
38
37
GND
MIPI_TX_2N436XGPIOC[20]C20
36
35
C16XGPIOC[16]432MIPI_TX_CN
MIPI_TX_2P437XGPIOC[21]C21
34
33
C17XGPIOC[17]433MIPI_TX_CP
GND
32
31
GND
MIPI_TX_1N430XGPIOC[14]C14
30
29
C12XGPIOC[12]428MIPI_TX_0N
MIPI_TX_1P431XGPIOC[15]C15
28
27
C13XGPIOC[13]429MIPI_TX_0P

Blue LED PIN

NAMESG2000NUM
LED
XGPIOA[29]509

Camera interface

DuoS has two CSI camera connectors:

  • J1 is a 16 PIN 0.5mm pitch connector compatible with Duo and Duo256M cameras, and can directly use the CAM-GC2083 camera.
  • J2 is a 15-pin 1.0mm pitch connector compatible with the Raspberry Pi camera interface. It currently supports the OV5647 camera used on the Raspberry Pi.
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Note that the I2C used by the J1 interface is I2C3, and the I2C used by the J2 interface is I2C2. Please check the pin multiplexing configuration when using it.

J1 Connector FPC Definition

J1Description
1GND
2MIPI0_DN0
3MIPI0_DP0
4GND
5MIPI0_DN1
6MIPI0_DP1
7GND
8MIPI0_CKN
9MIPI0_CKP
10GND
11SENSOR_RSTN0 (1.8V)
12SENSOR_CLK0 (1.8V)
13I2C3_SCL (1.8V)
14I2C3_SDA (1.8V)
15
163V3

J2 Connector FPC Definition

J2Description
13V3
2I2C2_SDA (3.3V)
3I2C2_SCL (3.3V)
4SENSOR_CLK1 (3.3V)
5SENSOR_RSTN1 (3.3V)
6GND
7MIPI0_DP5 (CAM1_CP)
8MIPI0_DN5 (CAM1_CN)
9GND
10MIPI0_DP4 (CAM1_DP1)
11MIPI0_DN4 (CAM1_DN1)
12GND
13MIPI0_DP3 (CAM1_DP0)
14MIPI0_DN3 (CAM1_DN0)
15GND

POE Header

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POE PinDescription
1VB-
2VB+
3VA-
4VA+

DuoS User Guide

RISC-V and ARM switching

The large core of DuoS can choose to use RISC-V or ARM processor, which can be set through the switch on the board. If you find that DuoS cannot start normally during use, please first check whether the switch is consistent with the firmware used.

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If the debug serial port is connected, you can see in the first line of the boot log that starting with C means starting from the RISC-V core, and starting with B means starting from the ARM core.

  • RISC-V:
    C.SCS/0/0.C.SCS/0/0.WD.URPL.USBI.USBW
  • ARM:
    B.SCS/0/0.WD.URPL.B.SCS/0/0.WD.URPL.USBI.USBW

Usage of USB Type A interface

The USB functions of the DuoS USB Type A interface and Type C interface are optional and cannot be used at the same time. The default firmware is configured with the USB network port (RNDIS) function of the Type C port. If you need to switch to the USB 2.0 HOST port of the Type A port for use with USB flash drives and other devices, you need to execute the following command:

ln -sf /mnt/system/usb-host.sh /mnt/system/usb.sh
sync

Then execute the reboot command or power on again to make it take effect.

For example, after connecting a USB flash drive to the USB A port, you can use ls /dev/sd* to check whether the device is detected.

Mount it to the system to view the contents of the USB flash drive (take /dev/sda1 as an example):

mkdir /mnt/udisk
mount /dev/sda1 /mnt/udisk

Check whether the contents of the /mnt/udisk directory are as expected:

ls /mnt/udisk

Command to uninstall USB flash drive:

umount /mnt/udisk

When you want to restore the USB network (RNDIS) function of the Type C port, execute:

rm /mnt/system/usb.sh
ln -sf /mnt/system/usb-rndis.sh /mnt/system/usb.sh
sync

Then execute the reboot command or power on again to make it take effect.

tip

DuoS has an onboard Ethernet interface, so the USB network port (RNDIS) of the Type C port can be used without switching to the USB 2.0 Host function of the A port.

UART Serial Console

Connect USB to TTL serial cable as shown below. Do not connect the red wire.

Milk-V DouS<--->USB to TTL
GND (pin 6)<--->Black wire
TX (pin 8)<--->White wire
RX (pin 10)<--->Green wire
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The default serial setting for Duo u-boot and kernel console is:

baudrate: 115200
data bit: 8
stop bit: 1
parity : none
flow control: none

WIFI configuration

Method 1

Edit the following file and replace ssid and psk with the WIFI account and password to be connected:

/etc/wpa_supplicant.conf
ctrl_interface=/var/run/wpa_supplicant
ap_scan=1
update_config=1

network={
ssid="wifi_test"
psk="12345678"
key_mgmt=WPA-PSK
}

Then execute the following command:

wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant.conf

You can connect to WIFI. After connecting, you can view the assigned IP address through the ifconfig or ip a command.

tip

If you need to automatically connect to the network at boot, you can put this command in the /mnt/system/auto.sh file.

eMMC version firmware burning

The DuoS eMMC version does not have firmware burned and needs to be burned using a PC through the USB interface.

tip

Use the USB burning tool under Windows to support eMMC. The firmware version is V1.1.0 or latest version.

Burning in Windows

  1. Install driver

    Download the USB driver installation tool: CviUsbDownloadInstallDriver.zip. After downloading, unzip and install.

  2. Download burning tool

    Download the command line burning tool under Windows CviBurn_v2.0_cli_windows.zip, unzip it after downloading.

  3. Download firmware

    Download the latest version of DuoS eMMC firmware, currently milkv-duos-emmc-v1.1.0-2024-0410.zip, you can create a new rom folder in the burning tool CviBurn_v2.0_cli_windows directory, and extract the downloaded eMMC firmware compressed package to rom directory, the directory structure of the burning tool is as follows:

    └───CviBurn_v2.0_cli_windows
    │ cv_dl_magic.bin
    │ usb_dl.exe
    └───rom
    │ boot.emmc
    │ fip.bin
    │ partition_emmc.xml
    │ rootfs_ext4.emmc
    | ...

    In the Windows terminal, execute the burning command in the CviBurn_v2.0_cli_windows directory:

    .\usb_dl.exe -s linux -c cv181x -i .\rom

    *You can also put the firmware in other directories and specify the corresponding directory through the -i parameter in the command. *

    Displays message waiting for USB connection:

    Document Pictures

    Use Type-C data cable to connect DuoS and PC (note, if DuoS currently has an SD card inserted, please remove the SD card first), DuoS will automatically power on and enter the burning mode, and the PC will display the burning status in real time. Recording progress:

    [INFO] Waiting for USB device connection: ---
    [INFO] found usb device vid=0x3346 pid=0x1000
    [INFO] downloading file: .\rom\boot.emmc
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 3384664/213100824(1%)
    [INFO] downloading file: .\rom\rootfs_ext4.emmc
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 20161944/213100824(9%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 36939224/213100824(17%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 53716504/213100824(25%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 70493784/213100824(33%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 87271064/213100824(40%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 104048344/213100824(48%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 120825624/213100824(56%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 137602904/213100824(64%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 154380184/213100824(72%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 171157464/213100824(80%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 187934744/213100824(88%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 204712024/213100824(96%)
    [INFO] CVI_USB_PROGRAM
    [INFO] updated size: 213100696/213100824(99%)
    [INFO] USB download complete

    After the burning is completed, the DuoS will automatically restart. After booting, you will see the blue LED on the DuoS flashing, indicating that the system has started normally and the burning is successful.

Hardware Docs

Others

https://github.com/milkv-duo/duo-files/tree/main/duo-s

  • carbonfix
  • hokamilkv