Nvidia JETSON XAVIER NX

Miscellaneous Interfaces
NVIDIA Jetson Xavier NX DG-09693-001_v1.7 | 76
12.6 Debug
Jetson Xavier NX supports a UART for debugging purposes. The UART intended for debug is
UART2 with is routed to a level shifter then to a 12-pin automation header on the developer kit
carrier board.
Table 12-13. Debug UART Pin Descriptions
Pin #
Module Pin
Name (see
note 4)
Xavier Signal Usage/Description
Recommended
Usage
Directio
n
Pin Type
238 UART2_RXD UART3_TX UART 2 receive
Debug UART
Input
CMOS –
1.8V
236 UART2_TXD UART3_RX UART 2 transmit Output
Note: In the Type/Dir column, Output is from Jetson Xavier NX. Input is to Jetson Xavier NX. Bidir is for Bidirectional signals.
Table 12-14. Debug UART Connections
Module Pin Name Type Termination Description
UART2_TXD O UART #2 Transmit: Connect to RX pin of serial device
UART2_RXD I If level shifter implemented,
100kΩ to supply on the non-
Jetson Xavier NX side of the
device.
UART #2 Receive: Connect to TX pin of serial device
Figure 12-8. Debug UART Connections
Jetson
SoC
Level Shifter
VCCB
VCCA
B1A1
B2A2
GNDOE
10 0kΩ
VDD_3V3_SYS
VDD_1V8
0.1uF 0.1uF
UART2_TXD
UART2_RXD
236
238
10 0kΩ
RXD_LS
TXD_L S
UART3_TX
UART3_RX
AO
Note: If level shifter is implemented, pull-up is required on the RXD line on the non-Jetson
Xavier NX side of the level shifter. This is required to keep the input from floating and toggling
when no device is connected to the debug UART.