Pin Assignments of Serial Communication App

Functions of pins used by the Serial Communication App

The following information applies to App_Uart v1.2 and later.

Unused pins should be left open.

TWELITE / TWELITE DIP

The functions of pins used by the Serial Communication App are represented using the pin names from the Super Simple! Standard App Pins shown in the figure below.

Super Simple! Standard App Pin Assignment Table

Serial Communication	Super Simple! Standard	Function
`VCC` `GND`	`VCC` `GND`	Power Input
`TX` `RX`	`TX` `RX`	Serial Input and Output
`TX_SUB` `RX_SUB`	`SCL` `SDA`	Serial Sub Input and Output
`RTS`	`PWM1`	Serial Input Permission
`M1`	`M1`	Parent/Child Selection
`M2`	`M2`	Adding Relay Function to Child
`M3`	`M3`	Sleep
`EX1`	`AI2`	Overwriting Operation Mode
`BPS`	`BPS`	Enabling Alternative Baud Rate Setting
`RST`	`RST`	Reset Input
`SET`	`DI1`	Enter interactive mode

Power Input

Connect a 3.3V (2.0-3.6V) power supply to VCC/GND.

Serial Input and Output

TX/RX are used for transmitting and receiving serial communication (UART).

Since the level is 3.3V, when connecting to microcontrollers operating at 5V levels such as Arduino, please perform level conversion.

Serial Sub Input and Output

TX_SUB (SCL) / RX_SUB (SDA) can be used as sub-ports for serial input and output.

Serial Input Permission

When RTS (PWM1) is at Low level, it indicates that serial input to RX is being accepted.

By suppressing input to RX when at High level, it is expected to prevent data loss.

Parent/Child Selection

Connecting M1 to GND sets the device as a parent, while leaving it open or connecting to VCC sets it as a child.

Setting via Interactive Mode

You can omit this connection and configure it via the interactive mode.

i set Device ID: 0

Adding Relay Function to Child

When M2 is connected to GND in child mode, relay functionality can be added.

Setting via Interactive Mode

You can omit this connection and configure it via the interactive mode.

r set Role: 1 or 0x12

Sleep

Connecting M3 to GND puts the device into sleep mode.

Overwriting Operation Mode

By connecting EX1 to GND at startup, the operation mode can be overwritten to format mode (binary).

Enabling Alternative Baud Rate Setting

Connecting BPS to GND enables the alternative baud rate setting specified in interactive mode.

Reset Input

By connecting a push button between RST and GND, a reset button can be implemented. RST has an internal pull-up resistor.

Enter interactive mode

By connection SET to GND on startup, the interactive mode will be ready.

TWELITE UART

The functions of pins used by the Serial Communication App are represented using the pin names of the 7P interface printed on the board (② in the figure below).

Silkscreen	Function
`VCC` `GND`	Power Input
`TXD` `RXD`	Serial Input and Output
`SET`	Overwriting Operation Mode
`RST`	Reset Input

Power Input

Connect a 3.3V (2.0-3.6V) power supply to VCC/GND.

Serial Input and Output

TX/RX are used for transmitting and receiving serial communication (UART).

When connecting to microcontrollers operating at 5V levels such as Arduino, please perform level conversion.

Overwriting Operation Mode

By connecting SET to GND at startup, the operation mode can be overwritten to format mode (ASCII).

Reset Input

By connecting a push button between RST and GND, a reset button can be implemented. RST has an internal pull-up resistor.