Product Info

Automotive Module Series
AG521R-NA QuecOpen Hardware Design
AG521R-NA_QuecOpen_Hardware_Design 50 / 104
⚫ Do not route signal traces under crystals, oscillators, magnetic devices, PCIe and RF signal traces. It
is important to route the USB differential traces in inner-layer with ground shielding on not only upper
and lower layers but also right and left sides.
⚫ If a USB connector is used, please keep the ESD protection components as close to the USB connector as
possible. Pay attention to the influence of junction capacitance of ESD protection components on USB data
lines. Typically, the capacitance value should be less than 2.0 pF for USB 2.0, and less than 0.4 pF for USB
3.0.
1. USB 2.0 and USB 3.0 share the same controller, therefore they cannot be used simultaneously.
2. “*” means under development.
3.11. UART Interfaces
The module provides three UART interfaces: UART1, BT UART and debug UART.
⚫ UART1 and BT UART support RTS and CTS hardware flow control, and are used for data transmission with
peripherals.
⚫ UART1 and BT UART support 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800 and 921600 bps
baud rates, and the default is 115200 bps.
⚫ The debug UART interface supports 115200 bps baud rate, and is used for Linux console and log output.
Table 13: Pin Definition of UART1 Interface
Pin Name
Pin No.
I/O
Description
Comment
UART1_CTS
71
DO
UART1 clear to send
1.8 V power domain.
Can be configured to GPIOs.
UART1_RTS
74
DI
UART1 request to send
UART1_TXD
70
DO
UART1 transmit
UART1_RXD
72
DI
UART1 receive
Table 14: Pin Definition of BT UART Interface
Pin Name
Pin No.
I/O
Description
Comment
BT_UART_TXD
59
DO
BT UART transmit
1.8 V power domain.
NOTES