Core Board

The core processing board hosts the Hailo15H SoC, NPU, memory, and storage subsystems. It exposes expansion interfaces to the interface board via board-to-board connectors. This document describes the hardware resources and pin definitions from a chip-level perspective.

Hardware Resource Overview

NE503 consists of the following physical modules:

Module	Main Chip	Description
Core Processing Board	Hailo15H SoC	SoC, NPU, memory, storage, I2C sensors, PCIe clock, Ethernet PHY
Interface Board	STM32G0B0RET6	MCU managing external IO, power, and peripheral control; TF card slot on board (see Interface Board)
Sensor Board	IMX678-AAQR1-C	4K CMOS image sensor, connected via FPC connector
Light Board	—	Dual-light board (white/red PWM) + IR light board (near/far-IR PWM)
Lens Module	AN41908A-VBA	AF auto-zoom and autofocus lens driver

The core board and interface board are interconnected via board-to-board connectors: the core board provides native SoC pins, and devices on the interface board are connected to these pins through the connectors.

Interface Overview

Core board resources are divided into two categories by physical location:

On-Board Resources — Physically soldered on the core processing board:

#	Function	Chip Model	Category
1	LPDDR4	MT53E2G32D4DE-046 WT:C	SoC built-in
2	eMMC	SDINBDA6-64G-H	SoC built-in
3	QSPI Flash	IS25WP064D-JKLE	SoC built-in
4	Temperature Sensor	TMP1075DSGR	On-board I2C
5	Gyroscope	LSM6DSR	On-board I2C
6	EEPROM	AT24C02D	On-board I2C
7	PCIe Clock	PI6CG18201	On-board I2C
8	PCIe & USB	Hailo15H built-in	SoC high-speed
9	Ethernet PHY	LAN8720AI	On-board RMII

Expansion Resources — Physically located on the interface board or external modules, connected through core board connector pins:

#	Function	Chip/Module	Connection	Category
10	Image Sensor	IMX678-AAQR1-C	MIPI CSI-2 + I2C0	Internal
11	TF Card	—	SDIO0 + GPIO	Product
12	Debug UART	—	UART0	Debug
13	BOOT Mode	—	BOOT0/BOOT1	Debug
14	Lens Driver	AN41908A-VBA	SPI (CS1)	Internal
15	Audio Codec	NAU88C10	I2S + I2C0	Internal
16	Radar Module	—	UART2 + GPIO	Internal
17	MCU Reset Control	SN74LVC1G14DCK	GPIO	Internal

SoC Built-in Resources

The following resources are directly connected via native SoC interfaces and physically soldered on the core processing board.

LPDDR4 (MT53E2G32D4DE-046 WT:C)

8 GB LPDDR4, 4266 Mb/s, 8.5 GB/s single-channel bandwidth.

Pin	Function
DDR_CH0_DQ0 ~ DDR_CH0_DQ15	Channel 0 data lines
DDR_CH1_DQ0 ~ DDR_CH1_DQ15	Channel 1 data lines
DDR_CH0_CA0 ~ DDR_CH0_CA5	Channel 0 command/address lines
DDR_CH1_DQS1N / DDR_CH1_DQS1P	Channel 1 data strobe differential pair
DDR_CH0_DQS1N / DDR_CH0_DQS1P	Channel 0 data strobe differential pair

eMMC (SDINBDA6-64G-H)

64 GB eMMC, connected directly to SoC SDIO1 interface.

Pin	Function
SDIO1_DAT0	Data line 0
SDIO1_DAT1	Data line 1
SDIO1_DAT2	Data line 2
SDIO1_DAT3	Data line 3
SDIO1_CMD	Command line
SDIO1_SDCLK	Clock line

QSPI Flash (IS25WP064D-JKLE)

8 MB, Quad SPI protocol, connected directly to SoC H_SPI interface.

Pin	Function
H_SPI_DQ0	FLASH_DQ0 (Data line 0)
H_SPI_DQ1	FLASH_DQ1 (Data line 1)
H_SPI_DQ2	FLASH_DQ2 (Data line 2)
H_SPI_DQ3	FLASH_DQ3 (Data line 3)
H_SPI_CLK	FLASH_CLK (Clock)
H_SPI_CS0	FLASH_CS0 (Chip select)

PCIe & USB

Hailo15H SoC native PCIe Gen4 and USB interfaces. PCIe clock provided by on-board PI6CG18201.

Ethernet PHY (LAN8720AI)

10/100M Ethernet PHY, IO voltage 1.6V ~ 3.6V, connected to SoC via RMII interface, providing wired network communication.

Pin	Function	Note
RMII_RXD0	ETH_RMII_RXD0	—
RMII_RXD1	ETH_RMII_RXD1	—
RMII_RX_ER	ETH_RMII_RXD2	SoC pin mux name
RMII_CRS_DV	ETH_RMII_RXD3	SoC pin mux name
RX_CLK	ETH_RMII_RX_CLK	RMII reference clock 50 MHz
RMII_TXD0	ETH_RMII_TXD0	—
RMII_TXD1	ETH_RMII_TXD1	—
RMII_TX_EN	ETH_RMII_TXD2	SoC pin mux name
MDIO	ETH_MDIO	—
MDC	ETH_MDC	—

On-Board I2C Devices

The following I2C devices are physically soldered on the core board, allocated by bus. Devices on the same bus are distinguished by different slave addresses.

I2C Bus	On-Board Device	Slave Address
I2C1	TMP1075 (Temperature Sensor), AT24C02D (EEPROM), PI6CG18201 (PCIe Clock)	0x49, 0x50, 0x6A
I2C2	LSM6DSR (Gyroscope)	0x6A

Note: PI6CG18201 (I2C1, address 0x6A) and LSM6DSR (I2C2, address 0x6A) are on different I2C buses, so there is no address conflict.

I2C0 bus is routed to the interface board via connectors, connecting IMX678 and NAU88C10 (see Expansion Interfaces below).

Temperature Sensor (TMP1075DSGR)

I2C1 slave address 0x49, 12-bit resolution, 0.0625°C.

Pin	Function
H_I2C1_SDA	I2C1 data line
H_I2C1_SCL	I2C1 clock line

Gyroscope (LSM6DSR)

I2C2 slave address 0x6A, integrated 3-axis accelerometer (±16 g) and 3-axis gyroscope (±4000 dps).

Pin	Function
I2C2_SDA	GPIO_6 (I2C2 data line)
I2C2_SCL	GPIO_7 (I2C2 clock line)

EEPROM (AT24C02D)

I2C1 slave address 0x50, 2 Kb (256 × 8), standby current < 1 µA.

Pin	Function
H_I2C1_SDA	I2C1 data line
H_I2C1_SCL	I2C1 clock line

PCIe Clock Generator (PI6CG18201)

I2C1 slave address 0x6A, 25 MHz, PCIe Gen4 low jitter 0.3 ps.

Pin	Function
H_I2C1_SDA	I2C1 data line
H_I2C1_SCL	I2C1 clock line

Expansion Interfaces

The following interfaces are routed through core board connectors. Physical devices are located on the interface board or external modules.

Image Sensor (MIPI CSI-2 + I2C0)

The core board connects to the image sensor via MIPI CSI-2 data lanes and I2C0 control bus. IMX678-AAQR1-C is located on a separate sensor board, connected via FPC connector. I2C0 slave address 0x10.

Pin	Function
CSI0_RX0P ~ CSI0_RX3N	MIPI CSI-2 data lanes (4 Lanes)
H_I2C0_SDA	I2C0 data line
H_I2C0_SCL	I2C0 clock line

Lens Driver (SPI CS1)

The core board SPI bus is routed via CS1 chip select to connect the AN41908A-VBA AF auto-zoom and autofocus lens driver. Shares SPI bus with QSPI Flash, distinguished by different chip selects. MCU SPI1 also connects to the same chip for homing and limit protection (see Interface Board).

Pin	Function
H_SPI_DQ0	FLASH_DQ0
H_SPI_DQ1	FLASH_DQ1
H_SPI_DQ2	FLASH_DQ2
H_SPI_DQ3	FLASH_DQ3
H_SPI_CLK	FLASH_CLK
H_SPI_CS1	FLASH_CS1 (Lens driver chip select)

Note: The function column names FLASH_DQ0 ~ FLASH_DQ3 and FLASH_CLK above come from the SoC QSPI controller pin naming. These pins are connected to the lens driver chip AN41908A via CS1 chip select, sharing the same data and clock lines as the QSPI Flash (CS0), distinguished by different chip select signals.

Audio Codec (I2S + I2C0)

The core board routes audio channels via I2S data interface and I2C0 control bus, connecting to the NAU88C10 audio codec (located on the interface board). I2C0 slave address 0x1A.

Pin	Function
H_I2S_SDI	I2S data input
H_I2S_SDO	I2S data output
H_I2S_WS	I2S word select
H_I2S_SCK	I2S clock
H_I2C0_SCL	I2C0 clock line
H_I2C0_SDA	I2C0 data line

UART2 (Radar Module)

Core board UART2 pins routed via connector for external radar module connection. Pins can be multiplexed as GPIO.

Pin	Function	Note
H_GPIO_4	UART2_TX	Can be multiplexed as GPIO
H_GPIO_6	UART2_RX	Can be multiplexed as GPIO, shared with I2C2_SDA
SAFETY_FATAL	Safety fault signal	—

SDIO0 (TF Card)

Core board SDIO0 interface routed via connector to the TF card slot on the interface board, supporting low-speed and high-speed modes.

Pin	Function
H_GPIO_17	Speed mode control (high = low-speed, low = high-speed)
SDIO0_DAT0	Data line 0
SDIO0_DAT1	Data line 1
SDIO0_DAT2	Data line 2
SDIO0_DAT3	Data line 3
SDIO0_CMD	Command line
SDIO0_SDCLK	Clock line

GPIO (MCU Reset Control)

Core board GPIO18 pin routed via connector to the SN74LVC1G14DCK reset chip for resetting the interface board MCU (STM32G0B0). In the reverse direction, the MCU can also reset the core processing board via PD8 (POWER_RST) (see Interface Board).

Pin	Function
H_GPIO_18	Reset control (active high)

Debug Interfaces

The following interfaces are used for system debugging and firmware flashing, with connectors located on the interface board.

UART0 (Debug Serial Port)

SoC native UART0, routed via connector for system debugging. This serial port has a dual role: it serves as the SoC debug serial port for system log output and interactive debugging, and also acts as the primary communication channel between the core processing board and the interface board MCU (STM32G0B0).

Pin	Function
SOC_UART0_RXD	UART0 receive
SOC_UART0_TXD	UART0 transmit

BOOT Mode

SoC boot mode configuration pins, routed via connector.

Pin	Function
BOOT0	Boot mode select 0
BOOT1	Boot mode select 1

SoC BootMode[0:1] configuration:

Mode	BOOT[1:0]
QSPI Flash	00
PCIe	01
UART	10