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无线更新演示应用程序
FreeRTOS 包括一个演示应用程序，用于演示空中下载 (OTA) 库的功能。OTA 演示应用程序位于 freertos/demos/ota/ota_demo_core_mqtt/ota_demo_core_mqtt.cfreertos/demos/ota/ota_demo_core_http/ota_demo_core_http.c
OTA 演示应用程序执行以下操作：
-
初始化 FreeRTOS 网络堆栈和 MQTT 缓冲池。
-
使用
vRunOTAUpdateDemo()创建任务来执行 OTA 库。 -
使用
_establishMqttConnection()创建 MQTT 客户端。 -
使用
IotMqtt_Connect()连接到 Amazon IoT MQTT 代理并注册 MQTT 断开连接回调：prvNetworkDisconnectCallback。 -
调用
OTA_AgentInit()创建 OTA 任务，并注册在 OTA 任务完成时使用的回调。 -
使用
xOTAConnectionCtx.pvControlClient = _mqttConnection;重用 MQTT 连接。 -
如果 MQTT 断开连接，应用程序将暂停 OTA 代理，尝试使用带有抖动的指数延迟重新连接，然后恢复 OTA 代理。
在使用 OTA 更新之前，请完成 FreeRTOS 空中下载更新 中的所有先决条件
在完成 OTA 更新的设置后，在支持 OTA 功能的平台上下载、构建、刷写并运行 FreeRTOS OTA 演示。设备特定的演示说明可用于以下取得 FreeRTOS 认证的设备：
在设备上构建、刷写并运行 OTA 演示应用程序后，您可以使用 Amazon IoT 控制台或 Amazon CLI 来创建 OTA 更新作业。在您创建 OTA 更新任务之后，连接到终端仿真器以查看 OTA 更新的进度。记下此过程中生成的任何错误。
成功 OTA 更新作业会显示类似以下内容的输出。为简便起见，在本示例中，我们删除了列表中的一些行。
249 21207 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 0 Queued: 0 Processed: 0 Dropped: 0 250 21247 [MQTT Agent Task] [core_mqtt.c:886] [INFO] [MQTT] Packet received. ReceivedBytes=601. 251 21247 [MQTT Agent Task] [core_mqtt.c:1045] [INFO] [MQTT] De-serialized incoming PUBLISH packet: DeserializerResult=MQTTSuccess. 252 21248 [MQTT Agent Task] [core_mqtt.c:1058] [INFO] [MQTT] State record updated. New state=MQTTPubAckSend. 253 21249 [MQTT Agent Task] [ota_demo_core_mqtt.c:976] [INFO] [MQTT] Received job message callback, size 548. 254 21252 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[execution.jobId: AFR_OTA-9702f1a3-b747-4c3e-a0eb-a3b0cf83ddbb] 255 21253 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[execution.jobDocument.afr_ota.streamname: AFR_OTA-945d320b-a18b-441b-b435-4a18d4e7671f] 256 21255 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[execution.jobDocument.afr_ota.protocols: ["MQTT"]] 257 21256 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[filepath: aws_demos.bin] 258 21257 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[filesize: 1164016] 259 21258 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[fileid: 0] 260 21259 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[certfile: ecdsa-sha256-signer.crt.pem] 261 21260 [OTA Agent Task] [ota.c:1575] [INFO] [OTA] Extracted parameter [ sig-sha256-ecdsa: MEQCIE1SFkIHHiZAvkPpu6McJtx7SYoD... ] 262 21261 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[fileType: 0] 263 21262 [OTA Agent Task] [ota.c:2199] [INFO] [OTA] Job document was accepted. Attempting to begin the update. 264 21263 [OTA Agent Task] [ota.c:2323] [INFO] [OTA] Job parsing success: OtaJobParseErr_t=OtaJobParseErrNone, Job name=AFR_OTA-9702f1a3-b747-4c3e-a0eb-a3b0cf83ddbb 265 21318 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 0 Queued: 0 Processed: 0 Dropped: 0 266 21418 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 0 Queued: 0 Processed: 0 Dropped: 0 267 21469 [OTA Agent Task] [ota.c:938] [INFO] [OTA] Setting OTA data interface. 268 21470 [OTA Agent Task] [ota.c:2839] [INFO] [OTA] Current State=[CreatingFile], Event=[ReceivedJobDocument], New state=[CreatingFile] 269 21482 [MQTT Agent Task] [core_mqtt.c:886] [INFO] [MQTT] Packet received. ReceivedBytes=3. 270 21483 [OTA Agent Task] [ota_demo_core_mqtt.c:1503] [INFO] [MQTT] SUBSCRIBED to topic $aws/things/__test_infra_thing71/streams/AFR_OTA-945d320b-a18b-441b-b435-4a18d4e7671f/data/cbor to bro 271 21484 [OTA Agent Task] [ota.c:2839] [INFO] [OTA] Current State=[RequestingFileBlock], Event=[CreateFile], New state=[RequestingFileBlock] 272 21518 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 0 Queued: 0 Processed: 0 Dropped: 0 273 21532 [MQTT Agent Task] [core_mqtt_agent_command_functions.c:76] [INFO] [MQTT] Publishing message to $aws/things/__test_infra_thing71/streams/AFR_OTA-945d320b-a18b-441b-b435-4a18d4e7671f/ 274 21534 [OTA Agent Task] [ota_demo_core_mqtt.c:1553] [INFO] [MQTT] Sent PUBLISH packet to broker $aws/things/__test_infra_thing71/streams/AFR_OTA-945d320b-a18b-441b-b435-4a18d4e7671f/get/cbor 275 21534 [OTA Agent Task] [ota_mqtt.c:1112] [INFO] [OTA] Published to MQTT topic to request the next block: topic=$aws/things/__test_infra_thing71/streams/AFR_OTA-945d320b-a18b-441b-b435-4a1 276 21537 [OTA Agent Task] [ota.c:2839] [INFO] [OTA] Current State=[WaitingForFileBlock], Event=[RequestFileBlock], New state=[WaitingForFileBlock] 277 21558 [MQTT Agent Task] [core_mqtt.c:886] [INFO] [MQTT] Packet received. ReceivedBytes=4217. 278 21559 [MQTT Agent Task] [core_mqtt.c:1045] [INFO] [MQTT] De-serialized incoming PUBLISH packet: DeserializerResult=MQTTSuccess. 279 21560 [MQTT Agent Task] [core_mqtt.c:1058] [INFO] [MQTT] State record updated. New state=MQTTPublishDone. 280 21561 [MQTT Agent Task] [ota_demo_core_mqtt.c:1026] [INFO] [MQTT] Received data message callback, size 4120. 281 21563 [OTA Agent Task] [ota.c:2464] [INFO] [OTA] Received valid file block: Block index=0, Size=4096 282 21566 [OTA Agent Task] [ota.c:2683] [INFO] [OTA] Number of blocks remaining: 284 ... // Output removed for brevity 3672 42745 [OTA Agent Task] [ota.c:2464] [INFO] [OTA] Received valid file block: Block index=284, Size=752 3673 42747 [OTA Agent Task] [ota.c:2633] [INFO] [OTA] Received final block of the update. (428298) ota_pal: No such certificate file: ecdsa-sha256-signer.crt.pem. Using certificate in ota_demo_config.h. 3674 42818 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 285 Queued: 285 Processed: 284 Dropped: 0 3675 42918 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 285 Queued: 285 Processed: 284 Dropped: 0 ... // Output removed for brevity 3678 43197 [OTA Agent Task] [ota.c:2654] [INFO] [OTA] Received entire update and validated the signature. 3685 43215 [OTA Agent Task] [ota_demo_core_mqtt.c:862] [INFO] [MQTT] Received OtaJobEventActivate callback from OTA Agent. ... // Output removed for brevity 2 39 [iot_thread] [INFO ][DEMO][390] ---------STARTING DEMO--------- [0;32mI (3633) WIFI: WIFI_EVENT_STA_CONNECTED [0;32mI (4373) WIFI: SYSTEM_EVENT_STA_GOT_IP ... // Output removed for brevity 4 351 [sys_evt] [INFO ][DEMO][3510] Connected to WiFi access point, ip address: 255.255.255.0. 5 351 [iot_thread] [INFO ][DEMO][3510] Successfully initialized the demo. Network type for the demo: 1 6 351 [iot_thread] [ota_demo_core_mqtt.c:1902] [INFO] [MQTT] OTA over MQTT demo, Application version 0.9.1 7 351 [iot_thread] [ota_demo_core_mqtt.c:1323] [INFO] [MQTT] Creating a TLS connection to <endpoint>-ats.iot.us-west-2.amazonaws.com:8883. 9 718 [iot_thread] [core_mqtt.c:886] [INFO] [MQTT] Packet received. ReceivedBytes=2. 10 718 [iot_thread] [core_mqtt_serializer.c:970] [INFO] [MQTT] CONNACK session present bit not set. 11 718 [iot_thread] [core_mqtt_serializer.c:912] [INFO] [MQTT] Connection accepted. ... // Output removed for brevity 17 736 [OTA Agent Task] [ota_demo_core_mqtt.c:1503] [INFO] [MQTT] SUBSCRIBED to topic $aws/things/__test_infra_thing71/jobs/notify-next to broker. 18 737 [OTA Agent Task] [ota_mqtt.c:381] [INFO] [OTA] Subscribed to MQTT topic: $aws/things/__test_infra_thing71/jobs/notify-next 30 818 [iot_thread] [ota_demo_core_mqtt.c:1850] [INFO] [MQTT] Received: 0 Queued: 0 Processed: 0 Dropped: 0 31 819 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[execution.jobId: AFR_OTA-9702f1a3-b747-4c3e-a0eb-a3b0cf83ddbb] 32 820 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[execution.statusDetails.updatedBy: 589824] 33 822 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[execution.jobDocument.afr_ota.streamname: AFR_OTA-945d320b-a18b-441b-b435-4a18d4e7671f] 34 823 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[execution.jobDocument.afr_ota.protocols: ["MQTT"]] 35 824 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[filepath: aws_demos.bin] 36 825 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[filesize: 1164016] 37 826 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[fileid: 0] 38 827 [OTA Agent Task] [ota.c:1645] [INFO] [OTA] Extracted parameter: [key: value]=[certfile: ecdsa-sha256-signer.crt.pem] 39 828 [OTA Agent Task] [ota.c:1575] [INFO] [OTA] Extracted parameter [ sig-sha256-ecdsa: MEQCIE1SFkIHHiZAvkPpu6McJtx7SYoD... ] 40 829 [OTA Agent Task] [ota.c:1684] [INFO] [OTA] Extracted parameter: [key: value]=[fileType: 0] 41 830 [OTA Agent Task] [ota.c:2102] [INFO] [OTA] In self test mode. 42 830 [OTA Agent Task] [ota.c:1936] [INFO] [OTA] New image has a higher version number than the current image: New image version=0.9.1, Previous image version=0.9.0 43 832 [OTA Agent Task] [ota.c:2120] [INFO] [OTA] Image version is valid: Begin testing file: File ID=0 53 896 [OTA Agent Task] [ota.c:794] [INFO] [OTA] Beginning self-test. 62 971 [OTA Agent Task] [ota_demo_core_mqtt.c:1553] [INFO] [MQTT] Sent PUBLISH packet to broker $aws/things/__test_infra_thing71/jobs/AFR_OTA-9702f1a3-b747-4c3e-a0eb-a3b0cf83ddbb/update to br63 971 [MQTT Agent Task] [core_mqtt.c:1045] [INFO] [MQTT] De-serialized incoming PUBLISH packet: DeserializerResult=MQTTSuccess. 65 973 [MQTT Agent Task] [core_mqtt.c:1058] [INFO] [MQTT] State record updated. New state=MQTTPublishDone. 64 973 [OTA Agent Task] [ota_demo_core_mqtt.c:902] [INFO] [MQTT] Successfully updated with the new image.