AURA SOM/AURA Evaluation Kit/Interfaces and Connectors/UARTs

History
Issue Date	Notes
2024/05/22	First release

UARTs interface

Description

The UARTs interface available on the Evaluation Kit are mapped to the following connectors:

• J21 is a standard DB9 male connector for the configurable UART2 port. The board provides some configuration options for the selection of the UART mode (RS232 at 2 or 4 wires)

DB9 configuration

• J25 is a 6x1x2.54mm horizontal socket header for the UART4 port. This is a Digilent Pmod™ Compatible connector for the UART Pmod™ Compatiblemodule (6-Pin Pmod™ Compatible Connector Digilent Pmod™ Interface Specification Type 4 UART)

PMOD configuration

Signals

The following tables describes the interface signals

UART2

In the schematics page 13, the signals label are referring to the original AXEL Lite EVK SOM's signals. UART5 is referencing the AXEL Lite UART connection and should be used just as a signal labels. For AURA EVK, the UART connected is UART2

Pin#	SOM Pin#	Pin name	RS-232
1	-	Not connected	Not connected
2	J10.95	UART5_A	UART2 receive line
3	J10.93	UART5_Y	UART2 transmit line
4	-	Not connected	Not connected
5	-	DGND	Ground
6	-	Not connected	Not connected
7	J10.105	UART5_Z	UART2 Request To Send
8	J10.107	UART5_B	UART2 Clear To Send
9	-	Not connected	Not connected

UART4

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	J10.50	PMOD_A0	Clear to send
2	J10.89	PMOD_A1	Transmit data
3	J10.91	PMOD_A2	Receive data
4	J10.40	PMOD_A3	Request to send
5	-	DGND	Ground
6	-	3V3	+3.3 V

Device mapping

• UART2 is mapped to /dev/ttyLP1 device in Linux
• UART4 is mapped to /dev/ttyLP3 device in Linux

Device usage

• UART2 is MultiProtocol supporting the RS232 protocol
• UART4 can be used with a PMOD adapter or with a TTL peripheral