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<div class="textblock"><h1><a class="anchor" id="autotoc_md77"></a>
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Put BLE functions in a task running on the NimBLE stack core</h1>
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<p>When commands are sent to the stack from a different core they can experience delays in execution. <br />
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This library detects this and invokes the esp32 IPC to reroute these commands through the correct core but this also increases overhead. <br />
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Therefore it is highly recommended to create tasks for BLE to run on the same core, the macro <code>CONFIG_BT_NIMBLE_PINNED_TO_CORE</code> can be used to set the core. <br />
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<br />
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</p>
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<h1><a class="anchor" id="autotoc_md78"></a>
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Do not delete client instances unless necessary or unused</h1>
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<p>When a client instance has been created and has connected to a peer device and it has retrieved service/characteristic information it will store that data for the life of the client instance. <br />
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If you are periodically connecting to the same devices and you have deleted the client instance or the services when connecting again it will cause a retrieval of that information from the peer again. <br />
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This results in significant energy drain on the battery of the devices, fragments heap, and reduces connection performance. <br />
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</p>
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<p>Client instances in this library use approximately 20% of the original bluedroid library, deleting them will provide much less gain than it did before. <br />
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</p>
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<p>It is recommended to retain the client instance in cases where the time between connecting to the same device is less than 5 minutes. <br />
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<br />
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<br />
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</p>
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<h1><a class="anchor" id="autotoc_md79"></a>
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Only retrieve the services and characteristics needed</h1>
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<p>As a client the use of <code><a class="el" href="class_nim_b_l_e_client.html#acb9007569b3bb13b3b49f3c4cb47b21a" title="Get a pointer to the vector of found services.">NimBLEClient::getServices</a></code> or <code><a class="el" href="class_nim_b_l_e_remote_service.html#a2c9e91c842598a6a9576c7b87af0863a" title="Get a pointer to the vector of found characteristics.">NimBLERemoteService::getCharacteristics</a></code> and using <code>true</code> for the parameter should be limited to devices that are not known. <br />
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Instead <code>NimBLEClient::getService(NimBLEUUID)</code> or <code>NimBLERemoteService::getCharacteristic(NimBLEUUID)</code> should be used to access certain attributes that are useful to the application. <br />
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This reduces energy consumed, heap allocated, connection time and improves overall efficiency. <br />
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<br />
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<br />
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</p>
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<h1><a class="anchor" id="autotoc_md80"></a>
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Check return values</h1>
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<p>Many user issues can be avoided by checking if a function returned successfully, by either testing for true/false such as when calling <code><a class="el" href="class_nim_b_l_e_client.html#ae9b3e8a9b47c7eaad040b485bda958a1" title="Connect to an advertising device.">NimBLEClient::connect</a></code>, <br />
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or nullptr such as when calling <code><a class="el" href="class_nim_b_l_e_client.html#ae22379ab10bd82932d2303fb3753c366" title="Get the service BLE Remote Service instance corresponding to the uuid.">NimBLEClient::getService</a></code>. The latter being a must, as calling a method on a nullptr will surely result in a crash. <br />
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Most of the functions in this library return something that should be checked before proceeding. <br />
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<br />
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<br />
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</p>
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<h1><a class="anchor" id="autotoc_md81"></a>
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There will be bugs - please report them</h1>
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<p>No code is bug free and unit testing will not find them all on it's own. If you encounter a bug, please report it along with any logs and decoded backtrace if applicable. <br />
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Best efforts will be made to correct any errors ASAP. <br />
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</p>
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<p>Bug reports can be made at <a href="https://github.com/h2zero/NimBLE-Arduino/issues">https://github.com/h2zero/NimBLE-Arduino/issues</a> or <a href="https://github.com/h2zero/esp-nimble-cpp/issues">https://github.com/h2zero/esp-nimble-cpp/issues</a>. <br />
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Questions and suggestions will be happily accepted there as well. </p>
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