Product Info

Wi-Fi&BT Module Series
FC21 Hardware Design
FC21_Hardware_Design 25 / 52
Figure 8: Reference Design for PCM Interface
3.5.2.4. BT_UART Interface
FC21 provides a dedicated UART interface for BT application. The following table shows the pin definition
of UART interface.
Table 12: Pin Definition of UART Interface
The following figure shows a reference design for UART interface connection between FC21 and
EC2x&EG2x-G.
Figure 9: Reference Design for UART Interface Connection
Pin Name Pin No. I/O Description Comment
BT_UART_RTS 7 DO BT UART request to send
1.8V power domain.
If unused, keep these
pins open.
BT_UART_CTS 8 DI BT UART clear to send
BT_UART_TXD 17 DO BT UART transmit data
BT_UART_RXD 18 DI BT UART receive data
批注 [RL9]: 中文是
BT_UART，这里是否需要改为
一致
批注 [RL10R9]: