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1808核心板外观

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Characteristic parameter


Pin pitchPin pitch

Core board system configuration
CPURK1808
Main frequencyDual-core A35 (1.6GHz)
NPU3.0Tops Computing power
RAMStandard 2GB, 1GB optional
MemoryStandard 8GB, 4GB/16GB optional
Power ICRK809,Support dynamic frequency modulation
Core board structure attributes
ExteriorStamp hole
size45mm*45mm
Number of pins144pin
1.2mm
8 floors
Core board electrical characteristics
Input voltage5V/2A
The output voltage3.3V/1.5A
Operating temperature-10~70℃
storage temperature-10~40℃
Main functional interface parameters supported by the core board
USB2.0 interface1 channel HOST2.0
USB3.0 interface1 channel TYPEC3.0, multiplexed with OTG
OTG interface1 way
UART interface8 channels, support flow control
PWM interface11 outputs
IIC interface6 outputs
SPI interface3 outputs
ADC interface4 outputs
Camera interface1 MIPI output
LCD interfaceMI pi
Touch interfaceCapacitive touch
audio portSupport earphone speaker output, support recording and playback
SD card interface2 way
emmc interfaceOnboard
Ethernet interfaceSupport Gigabit Ethernet
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Software upgrade instructions

LQ1808 has a flexible starting method. Under normal circumstances, unless the hardware is damaged, the LQ1808 development board will not be bricked.


If an accident occurs during the upgrade process and the bootloader is damaged, making it impossible to upgrade again, you can still enter the MaskRom mode to repair it.


Loading method


LQ1808 has 32KB BootRom and 2MB internal SRAM, and supports loading the system from the following devices:


SPI interface


eMMC interface


SDMMC interface


In addition, LQ1808 supports downloading system code from the USB OTG interface.


Start sequence


The startup sequence is as follows:


Main control power-on initialization


The BootRom code runs on SRAM to verify the bootloader in the storage device


After the verification is passed, load and run the bootloader boot code


The bootloader boot code is responsible for initializing the DDR memory, loading the complete bootloader code into the DDR memory and running


The bootloader loads the Linux kernel on the storage device and gives the execution rights to the Linux kernel


Start mode


LQ1808 has three startup modes:


Normal mode


Loader mode


MaskRom mode


Normal mode


Normal mode is the normal startup process. Each component is loaded in turn and enters the system normally.


Loader mode


In Loader mode, the bootloader will enter the upgrade state, waiting for host commands for firmware upgrades, etc. To enter the Loader mode, the bootloader must detect that the RECOVERY button is pressed during startup and the USB is connected. The method to make the device enter the upgrade mode is as follows:


Disconnect the power adapter


Connect the double male USB cable to the device and the host, and connect the board end to the USB3.0 OTG port.


Press and hold the RECOVERY button on the device.


Plug in the power source.


After about two seconds, release the RECOVERY button.


MaskRom mode


MaskRom mode is used to repair the system when the bootloader is damaged.


Generally, it is not necessary to enter the MaskRom mode. Only when the bootloader verification fails (the IDB block cannot be read, or the bootloader is damaged), the BootRom code will enter the MaskRom mode. At this time, the BootRom code waits for the host to transmit the bootloader code through the USB interface, load and run it.

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