Dave Embedded Systems SBC AXEL, User Manual

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S B C X U s e r ' s G u i d e v . 1 . 0 . 1
5.3.2 UART4 – J25
Fig. 14: UART4 connector
J25 is a is a 6x1x2.54 pitch vertical header for the UART4 port. This is a
Digilent Pmod™ Compatible connector for the UART Pmod™ Compatible
module:
◾ 6-Pin Pmod™ Compatible Connector (Digilent Pmod™ Interface
Specification Type 4 UART)
The following table reports the connector's pinout:
Pin # SOM pin
# Pin name Function 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
5.3.2.1 Accessing the peripheral
UART4 is mapped to /dev/ttymxc3 device in Linux:
root@axel-lite:~# dmesg | grep ttymxc3
[ 1.439339] 21f0000.serial: ttymxc3 at MMIO 0x21f0000 (irq =
61) is a IMX
Serial ports can be used through the standard serial programming API.
For detailed information, please refer to the Serial Programming HOWTO
December, 2019
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