T2-U Development Board

T2-U development board is designed for prototyping smart devices easily and quickly. You can use it with other purpose-built modules or development boards to evaluate your project.

Scenarios

T2-U development board applies to a wide range of scenarios.

• Develop with the board to build your IoT projects easily and fast.
• You can use this board for different development purposes.
  • Embedded program development and debugging
  • App development and debugging
  • Creating connected devices that can be controlled with a mobile phone
  • Getting started with IoT development and learning how the Wi-Fi-enabled control system works

Components

T2-U development board consists of Tuya’s highly-integrated Wi-Fi and Bluetooth module T2-U and peripherals including buttons, LED indicator, GPIOs, power, and USB-to-serial chip.

I/O port functions

• 1: Micro-USB (CN1): Inputs 5V DC voltage and provides two extended serial ports.

• 2: DIP switch (S1): Flip the toggle to the ON position to complete the circuit. The switch is used to open and close the circuit between the USB-to-serial chip and the chip’s serial port.

• 3: LED indicator (D3): When the 3.3V power is on, the LED is on.

• 4: Button (S2): When the button is pressed, P7 outputs low. When the button is released, it outputs high.

• 5: LED indicator (D2): When P26 outputs low, the LED is on.

• 6: Button (RST): When the button is pressed, the module is reset.

  Pin description

  No.	Symbol	Description
  1	NC	Leave it floating.
  2	3.3V	3.3V power pin.
  3	NC	Leave it floating.
  4	NC	Leave it floating.
  5	NC	Leave it floating.
  6	P26	Support hardware PWM5, corresponding to Pin 15 on the IC.
  7	P24	Support hardware PWM4, corresponding to Pin 16 on the IC.
  8	P28	A normal GPIO pin on T2-U, corresponding to Pin 10 on the IC.
  9	P9	A normal GPIO pin on T2-U, corresponding to Pin 25 on the IC.
  10	P17	A normal GPIO pin on T2-U, corresponding to Pin 14 on the IC. It can be reused as SPI_MISO.
  11	P15	A normal GPIO pin on T2-U, corresponding to Pin 13 on the IC. It can be reused as SPI_CS. It is not recommended to use this pin for non-SPI applications.
  12	5V	5V power pin.
  13	RST	Clock enable (CEN) pin on T2-U. It can output the chip enable and high enable signals.
  14	GND	Ground pin.
  15	NC	Leave it floating.
  16	TX1	UART_TX1 on T2-U to send user data, corresponding to Pin 27 on the IC.
  17	RX1	UART_RX1 on T2-U to receive user data, corresponding to Pin 26 on the IC.
  18	RST	Clock enable (CEN) pin on T2-U. It can output the high enable signal.
  19	GND	Ground pin.
  20	P14	A normal GPIO pin on T2-U, corresponding to Pin 11 on the IC. It can be reused as SPI_SCK.
  21	P16	A normal GPIO pin on T2-U, corresponding to Pin 12 on the IC. It can be reused as SPI_MOSI.
  22	RX2	UART_RX2 on T2-U to receive user data, labeled P1, corresponding to Pin 28 on the IC.
  23	TX2	UART_TX2 on T2-U to print logs, labeled P0, corresponding to Pin 29 on the IC.
  24	P20	A normal GPIO pin on T2-U, corresponding to Pin 20 on the IC.
  25	P22	A normal GPIO pin on T2-U, corresponding to Pin 18 on the IC.
  26	ADC	ADC on T2-U, labeled P23, corresponding to Pin 17 on the IC.
  27	P8	Support hardware PWM2, corresponding to Pin 24 on the IC.
  28	P7	Support hardware PWM1, corresponding to Pin 23 on the IC.
  29	P6	Support hardware PWM0, corresponding to Pin 22 on the IC.
  30	NC	Leave it floating.

Load-carrying capacity

• When micro-USB (CN1) inputs 5V DC voltage, the board can supply power to external components.

  Power pin	Rated voltage/current
  5V	Depends on the input current of the adapter connected to the DC-005 terminal.
  3.3V	3.3V/0.6A

• Characteristics of output voltage

  Output current	0A	0.15A	0.3A	0.45A	0.6A	0.75A
  Output voltage	3.34V	3.36V	3.37V	3.37V	3.38V	3.38V

  We tested the voltage under the condition that there is no output voltage on the micro-USB (CN1) terminal.

Schematic diagram and PCB

• The schematic diagram of the board:

  

• The PCB board:

  

USB to serial

The board has a built-in USB-to-serial chip. The single-channel USB port can provide two extended serial ports. You can flip the DIP switch (SW1) to enable the 2-channel serial port on the T2-U to connect to the USB-to-serial chip. The following table lists the pin definition of the DIP switch.

Connection for DOWNLOAD mode

The following figure shows the setup for flashing firmware using Tuya’s flashing and authorization software. Flip the toggles of channels 1 and 2 on the DIP switch (SW1) to the ON position to complete the circuit between the UART1 on T2-U and the host.

Connection for viewing logs on the host

Flip the toggles of channels 3 and 4 on the DIP switch (SW1) to the ON position to complete the circuit between the UART2 on T2-U and the host.

USB-to-serial chip driver

Download the USB-to-serial chip driver for your operating system.

• For Windows
• For Linux

Things to note

• The board has a built-in power supply port and circuit, so the additional power board is not necessary.
• This board only supports a USB port that supplies 5V output.