The IW9165E supports mapping GPIO pins to character devices (e.g., /dev/dio-x). These devices are exposed to the IOx framework, enabling customer-developed applications to programmatically access and manage digital I/O interfaces for external hardware control.

Best practices for digital I/O control

To ensure reliable and consistent operation of digital I/O ports, follow these best practices:

Use standardized paths: Always interact with the /dev/dio-x paths to ensure compatibility with the system's hardware abstraction layer.
Verify status: Read the exposed Digital I/O status using the supported device interface or status file for your application.

Control digital I/O ports

Manage external hardware signals and indicators through the command line interface.

You can use the character device interface to send high or low signals to hardware components or monitor the status of connected inputs.

Before you begin

Ensure the application environment is configured to access the /dev/ directory.

Follow these steps to control digital I/O ports:

Procedure

Use the echo command to set the output state of a digital I/O port.
- To set a port to high, use: echo 1 > /dev/dio-1
- To set a port to low, use: echo 0 > /dev/dio-1
Example:
```
Device# echo 1 > /dev/dio-1
```
Example:
```
Device# echo 0 > /dev/dio-1
```
Monitor the input status of a port by using the corresponding device file.
- To monitor the digital I/O output port status (high), use: echo 1 > /dev/dio-3
- To monitor the digital I/O output port status (low), use: echo 0 > /dev/dio-4
Example:
```
Device# echo 1 > /dev/dio-3
```
Example:
```
Device# echo 0 > /dev/dio-4
```
Control an LED by writing to the associated device file.
- To turn on the LED (1), use: echo 1 > /dev/dio-5
- To turn off the LED (1), use: echo 0 > /dev/dio-5
Example:
```
Device# echo 1 > /dev/dio-5
```
Example:
```
Device# echo 0 > /dev/dio-5
```

Digital I/O device mapping

The table lists the software-exposed device nodes used by the application environment.

Each entry specifies the device file corresponding to a digital I/O port configured for input or output and the device file that controls an LED indicator.
Mapping device files is essential for managing and interacting with hardware interfaces through programs or command-line operations.

Table 1. Device file mapping for digital I/O ports and LEDs
GPIOs	Digital I/O ports	Function
GPIO29	/dev/dio-1	Digital I/O 1 output
GPIO31	/dev/dio-2	Digital I/O 2 output
GPIO38	/dev/dio-3	Digital I/O 1 output
GPIO39	/dev/dio-4	Digital I/O 2 output
GPIO51	/dev/dio-5	LED 1
GPIO48	/dev/dio-6	LED 2

Note

The GPIOs in the table are the logical device nodes exposed to IOx.

Power saving modes

From release 26.2.1, Cisco IW9165E AP supports power saving modes through the exposed low-power control interface.

A power saving mode is a configuration state that

reduces energy consumption for devices powered by external battery sources,
maintains essential connectivity for remote management, and
enables automated control of connected peripherals.

Sleep modes

The AP supports two types of power saving modes:

Light sleep: In this mode, the device keeps the URWB backhaul radio on, and other radios and ethernet ports are shut down. The users can restore the device to active mode at any time via the backhaul radio. Enabling this mode reduces power consumption by 1.5 W to 2.4 W, depending on the traffic load.
Deep sleep: This mode is not supported in release 26.2.1.

Features of power saving modes

Automated control: Network administrators can use custom IOx applications to manage power states and control connected devices.
Application integration: The Cisco App-hosting Framework (CAF) facilitates communication between control systems and IOx applications to execute power-saving logic.

Note

Power saving modes are not persistent. The device will default to active mode after a reload or power cycle.

Manage power saving modes

Transition the device into a low-power state to conserve battery life during periods of inactivity.

Use this task when the device is deployed in mobile environments where power efficiency is required.

Before you begin

Ensure the IOx application is deployed and configured to communicate with your control system.
Verify that the necessary digital I/O interfaces are mapped to your IOx application. See Digital I/O device mapping section.

Follow these steps to manage power saving modes:

Procedure

Access your control system interface.

Example:

Engineering: How to access the control system interface?

Send the sleep command to the IOx application.
Example:
```
Device#: echo 1 > /mnt/host_cpu/low_power_mode
```
The IOx application executes the power-saving logic to transition the device to light sleep mode.
Send the wake-up command from your control system to the IOx application to restore full functionality.
Example:
```
Device# echo 0 > /mnt/host_cpu/low_power_mode
```
The IOx application executes the power-saving logic to transition the device to active mode.

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