User's Manual

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purpose; please specify the requirement when ordering, so that the onboard LED can be removed
during production.
2.2.1 LED Display
When an external LED to be used, a recommended connection shows as below:
Fig. 2- 3 Reference design for external LED connection
* the 470 ohm resistor can be changed to a value depends on the brightness of the LED.
2.3 UART interface
Table 2- 1 UART interface
The Super terminal or Tera or SecureCRT tool can be sued to test or debug the UART。
The UART setting is 115200，8-N-1; A reference design connection like:
Fig. 2- 4 UART reference connection diagram
UART interface
Pin Pin name I/O Instruction
4 RXD I UART_RXD(UART Receive data)
5 TXD O UART_TXD (UART transmit data)