Damien Frost
Example program to create IoT devices for a local network, which connect to a local server.
Dependencies: WebSocketClient WiflyInterface mbed messages
This code is used in the second part of my Internet of Things (IoT) blog post available here. The code is fairly simple, but its real value is in its reliability. I have worked hard to try to make the wireless connection as reliable, and as fast, as possible. There are a few lines of code that must be modified before it will work correctly, and those are described in the following Wiki pages.
It is designed to work with a Python WebSocket Server running on a PC, the source code of which is available here.
Once operating with the server, each microcontroller, or IoT device, will broadcast a counter and its internal temperature to your WebSocket Server.
main.cpp@5:0c7d131e6089, 2016-10-06 (annotated)
- Committer:
- defrost
- Date:
- Thu Oct 06 07:58:31 2016 +0000
- Revision:
- 5:0c7d131e6089
- Parent:
- 3:f20e114eb2ee
- Child:
- 8:5afd599875e4
- Added comments, cleaned up code
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| defrost | 5:0c7d131e6089 | 1 | /** |
| defrost | 5:0c7d131e6089 | 2 | * @author Damien Frost |
| defrost | 5:0c7d131e6089 | 3 | * |
| defrost | 5:0c7d131e6089 | 4 | * @section LICENSE |
| defrost | 5:0c7d131e6089 | 5 | * |
| defrost | 5:0c7d131e6089 | 6 | * Copyright (c) 2016 Damien Frost |
| defrost | 5:0c7d131e6089 | 7 | * |
| defrost | 5:0c7d131e6089 | 8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| defrost | 5:0c7d131e6089 | 9 | * of this software and associated documentation files (the "Software"), to deal |
| defrost | 5:0c7d131e6089 | 10 | * in the Software without restriction, including without limitation the rights |
| defrost | 5:0c7d131e6089 | 11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| defrost | 5:0c7d131e6089 | 12 | * copies of the Software, and to permit persons to whom the Software is |
| defrost | 5:0c7d131e6089 | 13 | * furnished to do so, subject to the following conditions: |
| defrost | 5:0c7d131e6089 | 14 | * |
| defrost | 5:0c7d131e6089 | 15 | * The above copyright notice and this permission notice shall be included in |
| defrost | 5:0c7d131e6089 | 16 | * all copies or substantial portions of the Software. |
| defrost | 5:0c7d131e6089 | 17 | * |
| defrost | 5:0c7d131e6089 | 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| defrost | 5:0c7d131e6089 | 19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| defrost | 5:0c7d131e6089 | 20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| defrost | 5:0c7d131e6089 | 21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| defrost | 5:0c7d131e6089 | 22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| defrost | 5:0c7d131e6089 | 23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| defrost | 5:0c7d131e6089 | 24 | * THE SOFTWARE. |
| defrost | 5:0c7d131e6089 | 25 | * |
| defrost | 5:0c7d131e6089 | 26 | * @file "main.cpp" |
| defrost | 5:0c7d131e6089 | 27 | * |
| defrost | 5:0c7d131e6089 | 28 | * @section DESCRIPTION |
| defrost | 5:0c7d131e6089 | 29 | * Simple Internet of Things main program. The device sends data every 3 |
| defrost | 5:0c7d131e6089 | 30 | * seconds, and can receive data from a server. |
| defrost | 5:0c7d131e6089 | 31 | * |
| defrost | 5:0c7d131e6089 | 32 | */ |
| defrost | 5:0c7d131e6089 | 33 | |
| defrost | 0:c5607b31fb07 | 34 | #include "mbed.h" |
| defrost | 1:4403f2ed1c1f | 35 | #include "globals.h" |
| defrost | 0:c5607b31fb07 | 36 | #include "WiflyInterface.h" |
| defrost | 1:4403f2ed1c1f | 37 | #include "Commands.h" |
| defrost | 0:c5607b31fb07 | 38 | #include "Websocket.h" |
| defrost | 1:4403f2ed1c1f | 39 | #include "ADC.h" |
| defrost | 0:c5607b31fb07 | 40 | |
| defrost | 2:7abdaa5a9209 | 41 | //#define DEBUG |
| defrost | 0:c5607b31fb07 | 42 | #define INFOMESSAGES |
| defrost | 0:c5607b31fb07 | 43 | #define WARNMESSAGES |
| defrost | 0:c5607b31fb07 | 44 | #define ERRMESSAGES |
| defrost | 0:c5607b31fb07 | 45 | #define FUNCNAME "IoT" |
| defrost | 0:c5607b31fb07 | 46 | #include "messages.h" |
| defrost | 0:c5607b31fb07 | 47 | |
| defrost | 5:0c7d131e6089 | 48 | |
| defrost | 0:c5607b31fb07 | 49 | // Main Loop! |
| defrost | 0:c5607b31fb07 | 50 | int main() { |
| defrost | 0:c5607b31fb07 | 51 | unsigned int wifi_cmd = NO_WIFI_CMD; |
| defrost | 0:c5607b31fb07 | 52 | float wifi_data = 0.0f; |
| defrost | 2:7abdaa5a9209 | 53 | unsigned int ADCRaw; |
| defrost | 5:0c7d131e6089 | 54 | char msg[128]; |
| defrost | 0:c5607b31fb07 | 55 | |
| defrost | 0:c5607b31fb07 | 56 | // Set the IoT ID: |
| defrost | 0:c5607b31fb07 | 57 | IoT_ID = 1; |
| defrost | 0:c5607b31fb07 | 58 | |
| defrost | 3:f20e114eb2ee | 59 | // Set the Auto reconnect flag: |
| defrost | 3:f20e114eb2ee | 60 | IotStatus.SetFlag(SF_AUTOCONNECT); |
| defrost | 3:f20e114eb2ee | 61 | |
| defrost | 0:c5607b31fb07 | 62 | // Send a startup message to serial port: |
| defrost | 1:4403f2ed1c1f | 63 | INFO(""); |
| defrost | 1:4403f2ed1c1f | 64 | INFO(""); |
| defrost | 0:c5607b31fb07 | 65 | INFO("Starting up..."); |
| defrost | 0:c5607b31fb07 | 66 | INFO("CPU SystemCoreClock is %d Hz", SystemCoreClock); |
| defrost | 5:0c7d131e6089 | 67 | |
| defrost | 5:0c7d131e6089 | 68 | // Configure the ADC to sample the internal temperature sensor. You cannot |
| defrost | 5:0c7d131e6089 | 69 | // use AnalogIn() unfortunately... |
| defrost | 2:7abdaa5a9209 | 70 | ConfigureADC(); |
| defrost | 5:0c7d131e6089 | 71 | |
| defrost | 5:0c7d131e6089 | 72 | // Connect to the wifi network. It will basically get stuck here until it |
| defrost | 5:0c7d131e6089 | 73 | // connects to the network. |
| defrost | 0:c5607b31fb07 | 74 | SetupNetwork(5000); |
| defrost | 5:0c7d131e6089 | 75 | |
| defrost | 0:c5607b31fb07 | 76 | // Configure the baud rate of the wifi shield: |
| defrost | 5:0c7d131e6089 | 77 | // This will make our wireless transmissions much faster. |
| defrost | 0:c5607b31fb07 | 78 | ws.setBaud(115200); |
| defrost | 0:c5607b31fb07 | 79 | wait(0.5f); |
| defrost | 0:c5607b31fb07 | 80 | |
| defrost | 5:0c7d131e6089 | 81 | // Check to see we are connected to the network: |
| defrost | 0:c5607b31fb07 | 82 | if(IotStatus.CheckFlag(SF_WIRELESSCONNECTED)){ |
| defrost | 5:0c7d131e6089 | 83 | // Try to connect to the WebSocket server: |
| defrost | 0:c5607b31fb07 | 84 | sprintf(msg, "ws://%s:%d/ws", SERVER_IP, WS_PORT); |
| defrost | 0:c5607b31fb07 | 85 | ws.Initialize(msg); |
| defrost | 0:c5607b31fb07 | 86 | INFO("Connecting to Websocket Server on %s...", msg); |
| defrost | 0:c5607b31fb07 | 87 | if(ws.connect()){ |
| defrost | 0:c5607b31fb07 | 88 | // Set a status flag: |
| defrost | 0:c5607b31fb07 | 89 | INFO("Connected."); |
| defrost | 0:c5607b31fb07 | 90 | IotStatus.SetFlag(SF_SERVERCONNECTED); |
| defrost | 0:c5607b31fb07 | 91 | }else{ |
| defrost | 0:c5607b31fb07 | 92 | // We could not connect right now.. |
| defrost | 0:c5607b31fb07 | 93 | IotStatus.ClearFlag(SF_SERVERCONNECTED); |
| defrost | 0:c5607b31fb07 | 94 | INFO("Could not connect to server, will try again later."); |
| defrost | 0:c5607b31fb07 | 95 | ReconnectAttempts++; |
| defrost | 0:c5607b31fb07 | 96 | } |
| defrost | 0:c5607b31fb07 | 97 | } |
| defrost | 0:c5607b31fb07 | 98 | |
| defrost | 5:0c7d131e6089 | 99 | // Start the display timer which will send data to the server every |
| defrost | 5:0c7d131e6089 | 100 | // 3 seconds. |
| defrost | 5:0c7d131e6089 | 101 | DisplayTimer.start(); |
| defrost | 3:f20e114eb2ee | 102 | |
| defrost | 5:0c7d131e6089 | 103 | // Inifinite main loop: |
| defrost | 0:c5607b31fb07 | 104 | while(1) { |
| defrost | 0:c5607b31fb07 | 105 | |
| defrost | 0:c5607b31fb07 | 106 | // Process the wifi command: |
| defrost | 0:c5607b31fb07 | 107 | if(wifi_cmd > NO_WIFI_CMD){ |
| defrost | 5:0c7d131e6089 | 108 | // Modify the desired variable: |
| defrost | 5:0c7d131e6089 | 109 | ModifyVariable(wifi_cmd, wifi_data); |
| defrost | 5:0c7d131e6089 | 110 | // Reset the command: |
| defrost | 0:c5607b31fb07 | 111 | wifi_cmd = NO_WIFI_CMD; |
| defrost | 0:c5607b31fb07 | 112 | } |
| defrost | 0:c5607b31fb07 | 113 | |
| defrost | 0:c5607b31fb07 | 114 | // Check for new wifi data: |
| defrost | 0:c5607b31fb07 | 115 | if((wifi_cmd == NO_WIFI_CMD)){ |
| defrost | 5:0c7d131e6089 | 116 | ReceiveNetworkData(&wifi_cmd, &wifi_data); |
| defrost | 0:c5607b31fb07 | 117 | } |
| defrost | 0:c5607b31fb07 | 118 | |
| defrost | 0:c5607b31fb07 | 119 | // Send the network data every 3 seconds: |
| defrost | 0:c5607b31fb07 | 120 | if(DisplayTimer.read()>(3.0f)){ |
| defrost | 1:4403f2ed1c1f | 121 | // Sample the internal temperature sensor: |
| defrost | 1:4403f2ed1c1f | 122 | STARTADCCONVERSION; |
| defrost | 5:0c7d131e6089 | 123 | // Wait for the conversion to complete: |
| defrost | 1:4403f2ed1c1f | 124 | while(!ADCCONVERSIONCOMPLETE); |
| defrost | 5:0c7d131e6089 | 125 | // Save the raw value from the ADC: |
| defrost | 2:7abdaa5a9209 | 126 | ADCRaw = ADC1->DR; |
| defrost | 5:0c7d131e6089 | 127 | // Calculate the temperature using information from the datasheet: |
| defrost | 2:7abdaa5a9209 | 128 | TempSensor = ((((float)ADCRaw)/ADC_MAX)*IT_VMAX - IT_V25)/IT_AVG_SLOPE + 25.0f; |
| defrost | 5:0c7d131e6089 | 129 | // Output the result: |
| defrost | 1:4403f2ed1c1f | 130 | DBG("TempSensor = %.5f", TempSensor); |
| defrost | 2:7abdaa5a9209 | 131 | DBG("ADC1->DR = %d", ADCRaw); |
| defrost | 0:c5607b31fb07 | 132 | |
| defrost | 0:c5607b31fb07 | 133 | // Send data over network: |
| defrost | 0:c5607b31fb07 | 134 | SendNetworkData(); |
| defrost | 0:c5607b31fb07 | 135 | |
| defrost | 0:c5607b31fb07 | 136 | // Increment a counter: |
| defrost | 0:c5607b31fb07 | 137 | SendCounter++; |
| defrost | 0:c5607b31fb07 | 138 | |
| defrost | 0:c5607b31fb07 | 139 | // Reset the timer: |
| defrost | 0:c5607b31fb07 | 140 | DisplayTimer.reset(); |
| defrost | 2:7abdaa5a9209 | 141 | |
| defrost | 0:c5607b31fb07 | 142 | } |
| defrost | 5:0c7d131e6089 | 143 | } // while(1) |
| defrost | 5:0c7d131e6089 | 144 | } // main() |