Wi-Fi&Bluetooth Module Series
FC905A_Hardware_Design 25 / 51
PCM
UART
FC905A
UART
PCM
HOST
BT_EN
BT_EN
GPIO1
HOST_WAKE_BT
GPIO2
BT_WAKE_HOST
Figure 5: Block Diagram of Bluetooth Application Interface Connection
3.6.1. UART Interface
FC905A supports an HCI UART as defined in
Bluetooth Core Specification Version 5.1
. The UART
supports hardware flow control, and it is used for data transmission with host. It supports up to 4.0 Mbps
baud rates.
Table 11: Pin Definition of UART Interface
The following figure shows a reference design for UART interface connection between FC905A and host.
Pin Name
Pin No.
I/O
Description
Comment
BT_RTS
41
DO
Bluetooth UART request to send
VIO power domain.
If unused, keep them open.
BT_TXD
42
DO
Bluetooth UART transmit
BT_RXD
43
DI
Bluetooth UART receive
BT_CTS
44
DI
Bluetooth UART clear to send