Product Overview

The Ra-01SCH-P is a LoRa series module designed and developed by Ai-Thinker. This module is used for ultra-long-distance spread spectrum communication.

Its RF chip LLCC68+ primarily uses the LoRa™ long-range modem for ultra-long-distance spread spectrum communication, with strong anti-interference capability and minimal current consumption. Leveraging Semtech's patented LoRa™ modulation technology, the module integrates a Power Amplifier (PA) and Low Noise Amplifier (LNA), achieving high sensitivity exceeding -137dBm and +29dBm transmit power for long transmission distances and high reliability. 

Meanwhile, compared with traditional modulation technology, LoRa™ modulation technology also has obvious advantages in anti-blocking and selectivity, solving the problem that traditional design solutions cannot simultaneously balance distance, anti-interference, and power consumption.

Application Scenarios

It can be widely used in automatic meter reading, home and building automation, security systems, remote irrigation systems, etc.

Features

  • Supports FSK, GFSK, LoRa® modulation methods;
  • Supports frequency band 803MHz~930MHz;
  • Maximum transmit power is optional

① Default configuration: internal PA uses 3.3V supply voltage; in this state, Tx Power can reach up to +29dBm with an operating current of 750mA;

② Optional configuration: internal PA uses 5V supply voltage; in this state, Tx Power can reach up to +31dBm with an operating current of 1A;

  • High sensitivity: as low as -137dBm@SF10 125KHz;
  • Extremely small size 17163.2(±0.2)MM, dual-row stamp hole patch package;
  • Supports spreading factors SF5/SF6/SF7/SF8/SF9/SF10/SF11;
  • Low power consumption in receiving state, with receive current as low as 16mA;
  • Module uses SPI interface, half-duplex communication, with CRC, up to 256-byte packet engine;
  • Supports multiple antenna installation methods, compatible with half-hole pads/through-hole pads/IPEX connector;


I. Software and Hardware Introduction

1. Code Download and Analysis

Obtain the relevant demo through the following link: https://aithinker-static.oss-cn-shenzhen.aliyuncs.com/docs/example/LLCC68-Ra-01SC-P_Ra-01SCH-P_Driver-V1.0.1.zip 

The NVIC_PriorityGroupConfig() function configures the interrupt priority grouping to 4, allocating all 4 bits for preemptive priority; PB12 pin is configured as a light control pin to indicate when the program sends or receives data; the clock is configured to execute the interrupt function every 1ms, with the interrupt function content shown below.

 

Where the functions ExampleLLCC68ReciveDemo() and ExampleLLCC68SendDemo() are used to set the Ra-01SCH-P module to select whether to use the module for receiving or sending.

1) ExampleLLCC68ReciveDemo() Function

The content of the ExampleLLCC68ReciveDemo() function is shown below:

 

Five callback functions are registered:

  • LLCC68OnTxDone(): Callback function executed when data transmission is completed;
  • LLCC68OnRxDone(): Callback function executed when data reception is completed;
  • LLCC68OnTxTimeout(): Callback function executed after data transmission timeout;
  • LLCC68OnRxTimeout(): Callback function executed after data reception timeout;
  • LLCC68OnRxError(): Callback function executed after data reception error;

 

The Radio.Init( &LLCC68RadioEvents ) function registers the above five callback functions. 

The Radio.SetChannel(LORA_FRE) function is used to set the RF frequency of the Ra-01SCH-P module. 

The Radio.SetTxConfig( MODEM_LORA, LORA_TX_OUTPUT_POWER, 0, LORA_BANDWIDTH, LORA_SPREADING_FACTOR, LORA_CODINGRATE, LORA_PREAMBLE_LENGTH, LORA_FIX_LENGTH_PAYLOAD_ON, true, 0, 0, LORA_IQ_INVERSION_ON, 3000 ) function is used to set the TX mode parameters of the Ra-01SCH-P module.

 

Function parameters:

LoRa mode, transmit power, FSK mode parameter (set to 0 for LoRa mode), bandwidth,...

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