Astro Carrier for NVIDIA® Jetson™ TX2/TX2i
Users Guide
Document: CTIM-00456
Revision: 0.24
Page 29 of 47
Date: 2021-10-04
Serial – HDC
The Astro Carrier features one display output interface using HDMI 2.0.
Function
HDMI
Function
Serial
Location
P2
HDC Bank
C
Pins
UART0 (/dev/ttyTHS2 within Linux for Tegra) – 135, 137, 141, 143
UART1: Default Serial Console (/dev/ttyS0 within Linux for Tegra) – 123, 125,
129, 131
Design Instruction
+/- 5.5V
No additional circuitry required
Transceiver placed on the Astro Carrier
Route direct to header/connector/device
Serial Configuration
Two Serial UART Links from the Jetson™ TX2/TX2i Module are routed into an Exar SP336E Transceiver.
This enables the various selectable serial outputs (RS-232/RS-485). To configure the setting, the
appropriate configuration of the Serial Selection DIP Switch (SW1) is required. Please refer to the Exar
SP336E datasheet for additional details.
Locked/Hardwired Configuration
The Astro Carrier comes populated with a control DIP Switch (SW1). The default setting for the serial
configuration on SW1 is Dual RS-232.
Dual RS-232
Switch SW1
Position
Description
A
OFF
Mode 0 Selection - RS-232 Selection
B
OFF
Serial Link 0 - RX+ BIAS
C
OFF
Mode 1 Selection - RS-232 Selection
D
OFF
Serial Link 0 - RX- BIAS
E
OFF
Serial Link 1 - RX+ BIAS
F
OFF
Serial Link 1 – RX- BIAS
Serial 0 RS-232/Serial 1 RS-485
Switch SW1
Position
Description
A
OFF
Mode 0 Selection - RS-232 Selection
B
OFF
Serial Link 0 - RX+ BIAS
C
ON
Mode 1 Selection - RS-485 Selection
D
OFF
Serial Link 0 - RX- BIAS
E
USER
Serial Link 1 - RX+ BIAS
F
USER
Serial Link 1 – RX- BIAS
