OTA Command: Wireless Control and Monitoring of I/Os
The OTA (Over The Air) Command function allows you to manage up to 4 digital inputs and 4 digital outputs both locally and remotely, simply via AT commands sent over the air.
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Setting remote outputs:
With the command AT+OTA_OUTx=1, for example, you can set OUT1 of the remote device to high level, with no need for physical wiring. |
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Reading remote inputs:
The command AT+OTA_RDINx=? lets you instantly check the status of digital inputs on a distant device. |
Practical advantages:
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Simplifies the implementation of remote control and monitoring systems. |
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Reduces installation and maintenance costs by eliminating the need for wiring between control points. |
Alarm Function: Immediate Notification of Critical Events
The Alarm function is designed for applications where promptness is crucial (security, environmental monitoring, industrial automation).
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How it works:
When one of the digital inputs (DIN0÷DIN3) changes state, the module automatically sends an alarm message via UART to the remote device:
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Alarm_0_1 → input switched to high level |
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Alarm_0_0 → input returned to low level |
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Typical applications:
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Door opening/closing alerts, fault detection, technical alarms. |
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Monitoring of environmental sensors (e.g., water level, temperature, presence). |
Remote I/O and Digital Mirroring: Bidirectional Synchronization
The Remote I/O function allows you to mirror the state of digital inputs from one station to the digital outputs of a remote station, and vice versa.
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Activation via AT+RemoteIO=1 |
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Instant synchronization: Any state change on a digital input of station A is immediately reflected on the corresponding output of station B, and vice versa. |
Practical example:
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In an automation system, pressing a button on one machine can activate a relay on a distant machine, with no delay and no wiring. |
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Ideal for distributed control systems, lighting automation, gates, pumps, etc. |
Competitive Advantages
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Flexibility: All functions are configurable via AT Command, both locally and remotely. |
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Security: Alarm notifications are immediate and reliable. |
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Efficiency: Digital mirroring eliminates the need for complex logic and reduces operational latency. |
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Scalability: Multiple modules can be managed in a network, enabling distributed control systems. |
Focus on Low Power Features: WOR (Wake-On-Radio)
One of the strengths of the RC-RCQ5-XXX is its intelligent energy management, essential for battery-powered devices or environments where operational continuity is critical.
Low Power Node Mode (LpNode):
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AT+LpNode: Activates low power mode. When enabled, the module adds a longer preamble to transmitted packets, allowing the receiver to "wake up" only when necessary. |
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AT+WOR_Duration: Allows you to configure the receiver’s wake-up frequency, choosing between 1000ms, 500ms, 250ms, and 125ms intervals. |
This architecture drastically reduces average consumption while maintaining the ability to receive data promptly. WOR is especially effective in wireless sensor systems, smart metering, and applications where battery life is critical.
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AT+LpUart: Enables low-power UART mode, maintaining data reception even when the microcontroller is in sleep mode. |
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Managed via dedicated pin (LP_UART_EN): UART is activated only when needed, with minimal consumption during standby. |
Focus on LBT (Listen Before Talk) Technology
To ensure robust and reliable communications in crowded environments, the RC-RCQ5-XXX implements the LBT technique:
What is LBT?
The Listen Before Talk (LBT) function allows the module to listen to the radio channel before transmitting. If the channel is free, transmission occurs; if busy, the module waits and retries according to configurable parameters.
Configurable parameters (AT+LBTP):
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RSSI threshold: Power level below which the channel is considered free (e.g., -60 dBm). |
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Number of attempts: How many times the module retries transmission if the channel is busy. |
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Random delay: Random wait interval between attempts to reduce collision probability. |
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Offset: Allows you to define a custom time window for backoff. |
LBT is based on a mechanism similar to CSMA/CD (Carrier Sense Multiple Access with Collision Detection), known in Ethernet networks but adapted for wireless. This approach reduces collisions, improves channel efficiency, and ensures coexistence with other RF devices.
Available Versions
Conclusion
The OTA, Alarm, Remote I/O, and mirroring features of the RC-RCQ5-XXX take wireless communication to the next level, offering control, responsiveness, and flexibility in any application scenario. In addition, advanced low-power management through WOR and LpUART,
and the LBT technique that ensures reliable transmissions even in congested radio environments, make it ideal for IoT, industrial, and automation applications where energy efficiency and reliability are fundamental requirements.
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