DESK-MX9-L/Peripherals/UART
| HOME | SOMs | SBCs | ToloMEO Embedded Assistant |  GET A QUOTE
|
 ONLINE HELPDESK
|
| Roadmap | IoT Services | ML/AI services | Embedded Design Services |
| History | |||
|---|---|---|---|
| Issue Date | Notes | ||
| 2024/01/30 | DESK-MX9-L-5.x.x release | ||
Contents
Peripheral UART[edit | edit source]
Device tree configuration[edit | edit source]
Here below is an example of device tree modifications to standard DAVE's kit for the AURA SOM:
From imx93-aura-cb2001.dts:
...
...
&lpuart4 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart4>;
status = "okay";
};
...
&iomuxc {
...
pinctrl_uart4: uart4grp{
fsl,pins = <
MX93_PAD_GPIO_IO14__LPUART4_TX 0x31e
MX93_PAD_GPIO_IO15__LPUART4_RX 0x31e
>;
};
...
Accessing the peripheral[edit | edit source]
Linux messages at boot time[edit | edit source]
... [ 0.847346] 44380000.serial: ttyLP0 at MMIO 0x44380010 (irq = 18, base_baud = 1500000) is a FSL_LPUART [ 0.856702] printk: console [ttyLP0] enabled [ 0.875438] 44390000.serial: ttyLP1 at MMIO 0x44390010 (irq = 19, base_baud = 1500000) is a FSL_LPUART [ 0.885307] 42580000.serial: ttyLP3 at MMIO 0x42580010 (irq = 20, base_baud = 1500000) is a FSL_LPUART [ 0.895137] 42690000.serial: ttyLP2 at MMIO 0x42690010 (irq = 21, base_baud = 1500000) is a FSL_LPUART ...
Usage with stty[edit | edit source]
N.B. UART mapping respect to ttyLPX is the following one:
LPUART1 <-> ttyLP0 LPUART2 <-> ttyLP1 LPUART3 <-> ttyLP2 LPUART4 <-> ttyLP3 ...
root@desk-mx93:~# stty -F /dev/ttyLP1 115200 -echo -raw root@desk-mx93:~# cat /dev/ttyLP1 > test_ttyLP1.log & [1] 716 root@desk-mx93:~# echo "Test loopback" > /dev/ttyLP1 root@desk-mx93:~# cat test_ttyLP1.log Test loopback root@desk-mx93:~#
Additional information[edit | edit source]
Serial ports can be used through the standard serial programming API.
For detailed information, please refer to the Serial Programming HOWTO at Serial-Programming-HOWTO
