IO
Definition
Module - Core-3588SJD4-AI
- Phoenix terminal pin definition
| GND | 485A | 485A | GND | CAN_H | 485A |
|---|---|---|---|---|---|
| 12V | 485B | 485B | GND | CAN_L | 485B |
| /dev/ttysWK2 re-de pin：GPIO122 | /dev/ttysWK1 re-de pin：GPIO35 | /dev/ttysWK0 re-de pin：GPIO34 |
- RS232 Interface Definition
| UP | /dev/ttyS9 |
|---|---|
| DOWN | /dev/ttyS6 |
Module - Core-3576JD4
- Phoenix terminal pin definition
| GND | 485A | 485A | GND | CAN_H | 485A |
|---|---|---|---|---|---|
| 12V | 485B | 485B | GND | CAN_L | 485B |
| /dev/ttysWK2 re-de pin：GPIO119 | /dev/ttysWK1 re-de pin：GPIO98 | /dev/ttysWK0 re-de pin：GPIO99 |
- RS232 Interface Definition
| UP | /dev/ttyS8 |
|---|---|
| DOWN | /dev/ttyS3 |
RS485 RE-DE PIN USE
For example, to operate 122, you need:
- Export the GPIO, run as root user:
echo 122 > /sys/class/gpio/export - Operate GPIO, set to read input or output specified value:
cd /sys/class/gpio/gpio122 # Set GPIO output mode echo out > direction # GPIO outputs low level, RS485 is set to data receiving mode echo 0 > value # GPIO outputs high level, RS485 is set to data receiving mode echo 1 > value
There are a few things to note:
- If the GPIO has been applied by other drivers, it cannot be exported successfully, and subsequent read and write operations cannot be performed.
- Involving the multiplexing of IO functions, if the function of the pin is already GPIO, the above method can be used; otherwise, the pinctrl state must be specified in the device tree.