ESP-Mosaico V1.0

[中文]

Note

This document covers CoreBoard V1.0 hardware. Please check the silkscreen version on the mainboard to confirm your board revision.

This guide helps you get started with ESP-Mosaico and provides detailed information about the board.

ESP-Mosaico is an expandable smart interaction development kit based on ESP32-S31. It targets magnetic expansion toys, motion sensing, square touch display HMI, and edge voice/multimedia applications. The device integrates a 480 × 480 QSPI square touch display, ES8311 audio codec, NS4150B amplifier, BMI270 6-axis IMU, dual BMM150 magnetometers, SPI NAND flash, and left/right 2 × 10P, 2.54 mm pitch module headers.

The main controller is Espressif ESP32-S31, supporting 2.4 GHz Wi-Fi 6 (IEEE 802.11b/g/n/ax), Bluetooth® 5.4 (LE + BR/EDR), and IEEE 802.15.4 (Thread / Zigbee). For storage, the board provides 16 MB in-package PSRAM, onboard 16 MB SPI NOR flash, and onboard 1 Gbit SPI NAND flash for graphics, multimedia, and asset caching. The display uses a CO5300-driven 480 × 480 QSPI square touch display with a CST9220-series touch controller.

For audio, ESP-Mosaico integrates ES8311 and NS4150B Class-D PA. The power system supports USB Type-C 5 V and a 3.7 V / 65 mAh Li-ion battery, with TP4057 charging, BQ27220 fuel gauge, and SAM8108 power-switch control. Both the Type-C port and the left/right module interfaces support power input and output. A USB 2.0 High-Speed OTG port supports power, debug, and communication, and the board also reserves UART expansion capability and left/right module interfaces.

ESP-Mosaico Appearance (Click to enlarge)

The document consists of the following major sections:

• Getting Started: Overview of the board and hardware/software setup instructions.

• Hardware Reference: More detailed information about the board hardware.

• Hardware Revision Details: Hardware revision history and known issues (if any).

• Related Documents: Links to related documentation.

• Disclaimer and Copyright Notice: Link to the disclaimer and copyright notice.

Getting Started

This section briefly introduces ESP-Mosaico and describes how to flash firmware and prepare the board.

Description of Components

ESP-Mosaico consists of a CoreBoard and a BaseBoard. The front views and their main components are shown first, followed by the back views and their main components.

Front

ESP-Mosaico Front (Click to enlarge)

ESP-Mosaico CoreBoard Front (Click to enlarge)

ESP-Mosaico BaseBoard Front (Click to enlarge)

The following describes the main components on the front PCB in clockwise order.

No.	Key Component	Description
	CoreBoard	Core board integrating the SoC, RF antenna, power management, display connector, audio codec, and sensors.
1	ESP32-S31NRV16	ESP32-S31 SoC, RISC-V 32-bit dual-core up to 320 MHz with 16 MB in-package PSRAM; supports 2.4 GHz Wi-Fi 6, Bluetooth 5.4 (LE + BR/EDR), and IEEE 802.15.4.
2	KH-3216-A35 Ceramic Antenna	2.4 GHz chip ceramic antenna for Wi-Fi and Bluetooth RF.
3	Orange LED	Programmable mono status LED on GPIO3, active-low.
4	TLV62569	Buck (DCDC) converter that converts the input supply to the system 3.3 V rail.
5	BMM150	3-axis magnetometer (BMM150 #2), I2C address 0x11.
6	SY7088	Boost (BOOST) converter for rails higher than the battery voltage.
7	Display Connector	Connects the 480 × 480, 2.16-inch QSPI touch display (CO5300 driver + CST9220 touch).
8	TP4057	Li-ion battery charger for the onboard battery.
9	BQ27220	Fuel gauge at I2C address 0x55 for voltage, current, state of charge (SOC), and related status.
10	3V3 Power LED	Lights when the 3.3 V rail is present after power-on; turns off when the device is powered off.
11	HUSB320	USB Type-C interface controller that handles CC detection and controls the USB power direction.
12	Charge LED	Charge status indicator: red while charging, green when fully charged.
13	SAM8108	Power on/off controller used with the POWER button.
14	HE9073A33	LDO providing a dedicated supply to the audio codec to reduce noise.
15	NS4150B	Low-EMI, filterless 3 W mono Class-D amplifier for the speaker.
16	ES8311	Low-power mono audio codec, I2C address 0x19, connected to the SoC over I2S.
17	BMM150	3-axis magnetometer (BMM150 #3), I2C address 0x12.
18	BMI270	6-axis IMU (accelerometer + gyroscope), I2C address 0x69.
19	GD25Q128EWIGR	16 MB (128 Mbit) SPI NOR flash for program and data storage.
20	GD5F1GM7UEYIGR	1 Gbit (128 MB) SPI NAND flash for large-capacity asset storage.
	BaseBoard	Base board integrating the speaker, battery, and left/right 2 × 10P module headers, mated to the CoreBoard through a board-to-board connector.
21	Speaker	Onboard speaker driven by the NS4150B amplifier.
22	BTB Connector	60-pin 0.5 mm board-to-board connector linking the CoreBoard and BaseBoard.
23	Expansion Header 1	2 × 10P dual-row, 2.54 mm pitch header exposing GPIOs and power for expansion.
24	Battery	3.7 V / 65 mAh Li-ion battery for portable power.
25	Expansion Header 2	Additional header exposing the remaining GPIOs and power.

Back

ESP-Mosaico Back (Click to enlarge)

ESP-Mosaico CoreBoard Back (Click to enlarge)

ESP-Mosaico BaseBoard Back (Click to enlarge)

The following describes the main components on the back PCB in clockwise order.

No.	Key Component	Description
	CoreBoard	Core board back side, exposing the buttons, Type-C connector, microphone, and vibration motor.
1	BTB Connector	Board-to-board connector mating with the BaseBoard (back side).
2	Vibration Motor	Vibration motor controlled by GPIO8 (active-high) for haptic feedback.
3	BOOT Button	Hold during power-up to enter firmware download mode.
4	LMA2718B331-OE1	Onboard microphone connected to the ES8311 for voice capture.
5	Type-C Connector	USB 2.0 High-Speed interface for power, debug/download, and USB communication, with Li-ion charging support.
6	POWER Button	Single press toggles the device power on/off.
7	Function Button	Application button (AI button) on GPIO7, active-low.
	BaseBoard	Base board back side, providing debug pads and back expansion power pads.
8	Debug Pads	Test points exposing GND / TX / RX / BOOT / EN / 3V3 debug signals.
9	Back Expansion Pads	Back-side expansion pads exposing I2C and power interfaces for supplying the device.

Start Application Development

Before powering up, make sure ESP-Mosaico is in good condition.

Required Hardware

• ESP-Mosaico

• USB cable (data-capable)

• Computer (Windows, Linux, or macOS)

Note

Be sure to use a proper USB data cable. Some cables are charge-only and cannot be used for data transfer or programming.

Hardware Notes

1. Flashing

   Connect ESP-Mosaico to the computer with a USB cable through the onboard Type-C port. This port is USB 2.0 High-Speed and supports both power delivery and USB data communication. The native ESP32-S31 chip only supports firmware download through this port in download mode, and does not provide auto-download or log output by itself. The factory firmware integrates a CDC virtual serial port and supports auto-download and serial log output. If flashing fails, try holding the BOOT button while the device is powered off, then power it on to enter download mode. In addition, the left and right module interfaces provide USB Serial/JTAG (left) and a TX/RX UART (right), both of which can be used for debugging and firmware download.

2. Power

   The Type-C port can power the device. The onboard battery is charged at a rated current of 65 mA. When a USB sink device is attached, the Type-C port automatically switches to source mode, with a maximum output of 5 V / 500 mA. If the load exceeds 1 A, the port shuts off automatically and recovers after a period of time. The left and right module interfaces also provide outward 3.3 V and 5 V rails (3V / 5V). These rails are output only when GPIO60 is driven low. VIN is an input supply pin that can also charge the onboard battery.

Software Setup

Follow the ESP-IDF Get Started guide to set up the development environment. The target chip for this board is esp32s31.

Note

The board communicates with the PC over USB. Most operating systems (Windows, Linux, macOS) already include the required drivers. If the device is not recognized or the serial connection fails, see Establish Serial Connection with ESP32-S31 for driver installation details.

BSP and Examples

Espressif provides a board support package (BSP) for ESP-Mosaico to simplify initialization of the LCD, touch, audio, sensors, battery, NAND flash, module resources, and USB console.

• BSP and examples: esp-mosaico

• Recommended application framework: ESP-Claw.

• After the first successful flash, use the BSP USB CDC console and auto-download support. Typical commands:

idf.py set-target esp32s31
idf.py -p /dev/ttyACM0 flash monitor

Note

• The first flash may require manually entering ROM download mode.

• The USB device briefly disconnects while the chip resets; IDF Monitor usually reconnects automatically.

• Use monitor --no-reset when attaching without restarting the application.

• Related options: CONFIG_BSP_USB_CONSOLE, CONFIG_BSP_USB_CONSOLE_AUTO_INIT, CONFIG_BSP_USB_AUTO_DOWNLOAD.

Hardware Reference

Block Diagram

The main components and connections of ESP-Mosaico are shown below.

ESP-Mosaico Block Diagram (Click to enlarge)

Power Supply Options

You can power the board in the following ways:

1. Through the Type-C (USB-C) port

   Connect a USB Type-C cable to the Type-C port.

2. Through the back expansion pads

   Supply external power through the back expansion pads on the BaseBoard.

3. Through the battery

   The board supports a 3.7 V / 65 mAh Li-ion battery.

Regardless of the power source, use the POWER button to turn the device on or off. External power sources above can also charge the onboard battery.

Type-C Interface

Type-C Interface Schematic (Click to enlarge)

The Type-C port connects to ESP32-S31 USB 2.0 High-Speed OTG for power, debug, and application communication. Onboard USB Serial/JTAG signals are used for download and debugging. The BSP USB CDC console and auto-download feature are the recommended download and log path.

DCDC 3.3 V Circuit

DCDC 3.3 V Schematic (Click to enlarge)

TLV62569 steps VDD down to MCU_3V3, which is then switched to VCC_3V3 by the VCC_PW load switch. U7 is the 3.3 V power LED.

Power-control GPIOs defined by the BSP:

Signal	GPIO	Description
VCC_3V3 / VCC_PW	GPIO60	System 3.3 V rail control, active-low; BSP applies a soft-start ramp when enabling.
CODEC_3V3	GPIO56	Codec power control, active-high.
POWER_SWITCH	GPIO57	Whole-device power-off request; kept high-Z during normal BSP operation, driven open-drain low to request shutdown.

BOOST Circuit

BOOST Schematic (Click to enlarge)

The onboard SY7088 boost converter is enabled by VCC_3V3 and outputs VOUT_BOOST for rails higher than the battery voltage.

Power On/Off Circuit

Power On/Off Schematic (Click to enlarge)

SAM8108 works with the POWER button for whole-device power control. The POWER_SWITCH signal can also be monitored or driven by software to request shutdown.

MCU and Pin Assignment

The following table lists the main pin assignments used by the ESP-Mosaico BSP, grouped by function.

ESP-Mosaico Main Pin Assignment

Category	Signal	GPIO	Description
I2C / Sensors	I2C0_SDA	GPIO0	Shared I2C for touch, ES8311, BMI270, BMM150, BQ27220, and module EEPROM
	I2C0_SCL	GPIO1	Shared I2C clock
	SENSOR_INT	GPIO2	IMU / magnetometer interrupt or signal
	TOUCH_INT	GPIO6	Touch interrupt
HMI	STATUS_LED	GPIO3	Orange status LED, software-controlled, active-low
	AI_BUTTON	GPIO7	Application button, active-low
	MOTOR	GPIO8	Vibration motor, active-high
LCD	LCD_DATA3	GPIO9	CO5300 QSPI DATA3
	LCD_DATA2	GPIO35	CO5300 QSPI DATA2
	LCD_DATA0	GPIO36	CO5300 QSPI DATA0
	LCD_RST	GPIO42	LCD reset
	LCD_TE	GPIO43	LCD_TE anti-tearing sync
	LCD_SCL	GPIO44	QSPI clock
	LCD_CS	GPIO50	LCD chip select
	LCD_DATA1	GPIO51	CO5300 QSPI DATA1
Audio	I2S_BCK	GPIO37	Audio bit clock
	I2S_DOUT	GPIO40	Audio data out (DAC)
	PA_CTRL	GPIO45	Amplifier enable
	I2S_WS	GPIO49	Audio word select
	I2S_DIN	GPIO52	Audio data in (ADC)
	I2S_MCLK	GPIO54	Audio master clock
	CODEC_PW	GPIO56	Codec 3.3 V power control
Power	POWER_SWITCH	GPIO57	Power on/off request
	VCC_3V3_CTRL	GPIO60	System 3.3 V power control
NAND Flash	NAND_CLK	GPIO20	SPI NAND (SD_D0)
	NAND_D	GPIO21	SPI NAND (SD_D1 / SIO0)
	NAND_Q	GPIO22	SPI NAND (SD_D2 / SIO1)
	NAND_CS	GPIO23	SPI NAND (SD_D3)
	NAND_HOLD	GPIO24	SPI NAND (SD_CLK / SIO3)
	NAND_WP	GPIO25	SPI NAND (SD_CMD / SIO2)

I2C Device Addresses

The 7-bit addresses on the shared I2C bus (I2C0_SDA / I2C0_SCL) are listed below. Onboard devices are on the CoreBoard / BaseBoard. Module EEPROMs are on the attached modules, not on the mainboard, and appear only when a module with EEPROM is plugged into the corresponding slot.

I2C Address	Device	Description
0x11	BMM150 #2	Onboard 3-axis magnetometer
0x12	BMM150 #3	Onboard 3-axis magnetometer
0x19	ES8311	Onboard audio codec
0x50	Module EEPROM (Left)	On the left module, not the mainboard; selected when GPIO14 is driven low
0x51	Module EEPROM (Right)	On the right module, not the mainboard; selected when GPIO39 is driven high
0x55	BQ27220	Onboard fuel gauge
0x5A	CST9220	Onboard touch controller
0x69	BMI270	Onboard 6-axis IMU

LCD Interface

LCD Interface Schematic (Click to enlarge)

• LCD driver: CO5300, QSPI interface, 480 × 480 resolution.

• Touch controller: CST9220 series, I2C interface (TP_SCL / TP_SDA / TP_RST / TP_INT).

Vibration Motor Interface

Vibration Motor Schematic (Click to enlarge)

The vibration motor is driven by MOTOR (GPIO8) through a low-side MOSFET, active-high.

Module Interface

The BaseBoard provides two 2 × 10P, 2.54 mm pitch expansion headers (H2 left and H1 right) that expose GPIOs, UART, USB Serial/JTAG, power, and ground for secondary development. Except for power and ground, all expansion signal pins support GPIO and can be flexibly remapped through the GPIO matrix. Labels such as ADC / TOUCH / COMP / DAC in the tables below mark the pin’s analog capabilities and do not prevent using it as a general-purpose GPIO.

ESP-Mosaico provides left and right module slots. The BSP discovers them through EEPROM address selection:

Slot	EEPROM Address	Description
Left (H2)	0x50	Address-select GPIO14, driven low
Right (H1)	0x51	Address-select GPIO39, driven high; mounted 180° relative to the left slot

Left Module Slot (H2) Pins

Left Module Interface Schematic (Click to enlarge)

Pins are listed clockwise around the connector, starting from Pin1 (odd-numbered row first, then even-numbered row back).

Pin	Signal	Description
1	GPIO55	ADC
3	GPIO19	ADC
5	GPIO18	TOUCH
7	GPIO17	TOUCH
9	GPIO16	TOUCH
11	GPIO15	TOUCH
13	USJ_DN (GPIO33)	USB Serial/JTAG D-
15	USJ_DP (GPIO34)	USB Serial/JTAG D+
17	5V_IN	External 5 V input (can power and charge the device)
19	VCC_3V3	3.3 V output (controlled by GPIO60)
20	GND	Ground
18	5V_OUT	5 V output (controlled by GPIO60)
16	GPIO0	SDA (shared onboard I2C)
14	GPIO1	SCL (shared onboard I2C)
12	GPIO4	DAC
10	GPIO14	TOUCH; EEPROM address select
8	GPIO12	TOUCH
6	GPIO13	TOUCH
4	GPIO48	ADC
2	GPIO53	ADC

Right Module Slot (H1) Pins

Right Module Interface Schematic (Click to enlarge)

Pins are listed clockwise around the connector, starting from Pin1 (odd-numbered row first, then even-numbered row back).

Pin	Signal	Description
1	GPIO49 *	ADC; multiplexed with codec I2S_WS
3	GPIO52 *	ADC; multiplexed with codec I2S_DIN
5	GPIO54 *	ADC; multiplexed with codec I2S_MCLK
7	GPIO37 *	COMP; multiplexed with codec I2S_BCK
9	GPIO40 *	COMP; multiplexed with codec I2S_DOUT
11	GPIO38	COMP
13	RX0 (GPIO59)	UART RX
15	TX0 (GPIO58)	UART TX
17	5V_IN	External 5 V input (can power and charge the device)
19	VCC_3V3	3.3 V output (controlled by GPIO60)
20	GND	Ground
18	5V_OUT	5 V output (controlled by GPIO60)
16	GPIO0	SDA (shared onboard I2C)
14	GPIO1	SCL (shared onboard I2C)
12	GPIO5	DAC
10	GPIO39	TOUCH; EEPROM address select
8	GPIO10	TOUCH
6	GPIO11	TOUCH
4	GPIO47	ADC
2	GPIO46	ADC

Important

Pins marked with * (5 in total) are multiplexed with the onboard audio codec I2S bus: GPIO49 (I2S_WS), GPIO52 (I2S_DIN), GPIO54 (I2S_MCLK), GPIO37 (I2S_BCK), and GPIO40 (I2S_DOUT). These pins can be used for module expansion only when codec audio is not required. Do not use them for expansion if the application still needs the onboard ES8311 / speaker / microphone path.

Note

When the left camera module claims DVP pins, GPIO14 (EEPROM address-select) is reused as DVP D4 and EEPROM access to that slot is suspended until the camera resource is released.

Hardware Revision Details

No previous versions.

Related Documents

• ESP-Mosaico CoreBoard V1.0 Schematic (PDF)

• 2.16-inch 480 × 480 QSPI AMOLED Display Datasheet (PDF)

• ESP32-S31 Series Datasheet (HTML)

• ESP-Mosaico BSP and examples: esp-mosaico repository

• ESP-Claw (HTML)

Disclaimer and Copyright Notice

Please refer to the Disclaimer and Copyright Notice.