{"id":1363,"date":"2021-11-19T14:36:18","date_gmt":"2021-11-19T14:36:18","guid":{"rendered":"https:\/\/smartsensordevices.com\/?p=1363"},"modified":"2021-11-19T14:36:28","modified_gmt":"2021-11-19T14:36:28","slug":"bluetooth-low-energy-ble-tutorial-for-arduino-using-bleuio","status":"publish","type":"post","link":"https:\/\/smartsensordevices.com\/blog\/bluetooth-low-energy-ble-tutorial-for-arduino-using-bleuio\/","title":{"rendered":"Bluetooth Low Energy (BLE) Tutorial for Arduino using BleuIO"},"content":{"rendered":"\n

1. Introduction<\/h2>\n\n\n\n

The project is a simple example showcasing a quick way to setup an Arduino with a USB Host Shield as a USB CDC Host capable of communicating with the BleuIO Dongle.<\/p>\n\n\n\n

When a BleuIO Dongle is connected to the USB port, the BleuIO Dongle will start advertising. It will then act as a terminal, taking input and sending data to the Arduino Virtual Com Port.<\/p>\n\n\n\n

We have used an Arduino Uno Rev. 3 with SparkFun\u2019s USB Host Shield (DEV-09947) for this example.<\/p>\n\n\n\n

2. About the Code<\/h2>\n\n\n\n

You can get project HERE<\/strong><\/a>
https:\/\/github.com\/smart-sensor-devices-ab\/arduino_bleuio_example<\/a>
This project based on the \u2018acm_terminal\u2019 example in the Host USB Shield Library 2.0<\/a>

\"alt<\/p>\n\n\n\n

The largest possible max.packet size for the function Acm.RcvData() is 64 bytes, so to accommodate the amount of data we will receive, we are using three buffers to receive the data from the BleuIO Dongle.<\/p>\n\n\n\n

If the buffers have received any data, we print it out to the serial terminal connected to the Virtual COM Port.<\/p>\n\n\n\n

void loop()\n{\n    Usb.Task();\n\n    if( Acm.isReady()) {\n       uint8_t rcode;\n       uint8_t rcode2;\n       uint8_t rcode3;\n\n       \/* reading the keyboard *\/\n       if(Serial.available()) {\n         uint8_t data= Serial.read();\n         \/* sending to the BleuIO Dongle *\/\n         rcode = Acm.SndData(1, &data);\n         if (rcode)\n            ErrorMessage<uint8_t>(PSTR(\"SndData\"), rcode);\n       }\/\/if(Serial.available()...\n\n        if(start_flag == 0x00)\n        {\n            rcode = Acm.SndData(strlen((char *)START_CMDS), (uint8_t *)START_CMDS);\n            if (rcode)\n            {\n                ErrorMessage<uint8_t>(PSTR(\"SndData\"), rcode);\n            }\n\n          start_flag = 0x01;\n        }\n        \/* reading the BleuIO Dongle *\/\n        uint8_t  buf[64];\n        uint16_t rcvd = 64;\n        uint8_t  buf2[64];\n        uint16_t rcvd2 = 64;\n        uint8_t  buf3[64];\n        uint16_t rcvd3 = 64;\n        uint8_t  dongle_input[3*64];\n        uint16_t input_indx = 0;\n\n        memset(dongle_input, 0, sizeof(dongle_input));\n\n        rcode = Acm.RcvData(&rcvd, buf);\n        delay(1);\n        rcode2 = Acm.RcvData(&rcvd2, buf2);\n        delay(1);\n        rcode3 = Acm.RcvData(&rcvd3, buf3);\n         if (rcode && rcode != hrNAK)\n         {\n            ErrorMessage<uint8_t>(PSTR(\"Ret\"), rcode);\n         }\n\n         if (rcode2 && rcode2 != hrNAK)\n         {\n             ErrorMessage<uint8_t>(PSTR(\"Ret\"), rcode2);\n         }\n\n         if (rcode3 && rcode3 != hrNAK)\n         {\n             ErrorMessage<uint8_t>(PSTR(\"Ret\"), rcode3);\n         }\n\n\n            if( rcvd ) { \/\/more than zero bytes received\n              for(uint16_t i=0; i < rcvd; i++ ) {\n                Serial.print((char)buf[i]); \/\/printing on the screen\n                dongle_input[input_indx] = buf[i];\n                input_indx++;\n              }\n            }\n\n            if( rcvd2 ) { \/\/more than zero bytes received\n              for(uint16_t i=0; i < rcvd2; i++ ) {\n                Serial.print((char)buf2[i]); \/\/printing on the screen\n                dongle_input[input_indx] = buf2[i];\n                input_indx++;\n              }\n            }\n\n            if( rcvd3 ) { \/\/more than zero bytes received\n              for(uint16_t i=0; i < rcvd3; i++ ) {\n                Serial.print((char)buf3[i]); \/\/printing on the screen\n                dongle_input[input_indx] = buf3[i];\n                input_indx++;\n              }\n            }\n            dongle_input[input_indx] = 0x00;\n\n            \/\/ Example on a way for the Arduino to react to BleuIO events\n            if(strlen((char *)dongle_input) != 0)\n            {\n              if(strstr((char *)dongle_input, \"handle_evt_gap_connected\") != NULL)\n              {\n                Serial.print(\"<<CONNECTION DETECTED!>>\");\n              }\n              else if(strstr((char *)dongle_input, \"handle_evt_gap_disconnected\") != NULL)\n              {\n                Serial.print(\"<<CONNECTION LOST!>>\");\n              }\n            }\n    }\/\/if( Usb.getUsbTaskState() == USB_STATE_RUNNING..\n}<\/code><\/pre>\n\n\n\n
We also store the latest data from the dongle into the dongle_input buffer and run it through a simple \u201cparser\u201d to showcase an easy way of how you can react to events and have the Arduino do something.<\/p>\n\n\n\n
In this example, we are explicitly looking for BLE connection or disconnect events. When found, we just print out \u201c<<CONNECTION DETECTED!>>\u201d or \u201c<<CONNECTION LOST!>>\u201d to the terminal.<\/p>\n\n\n\n
3. Using the example project<\/h2>\n\n\n\n
3.1 What you will need<\/h4>\n\n\n\n