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Spidey Wall is the name for a physical wall lit up by multiple addressable LED strips. This program is an LPC1768 web server to control the wall from a browser.
Dependencies: EthernetInterfacePlusHostname RdWebServer mbed-rtos mbed
This project is part of a Light-Wall using addressable LED strips (WS2801). I have published a few posts on my blog about the construction of the wall and building a game to play on it (PacMan). I have also had a guest post from a friend who has set his children the task of producing some interesting animations. The original post is http://robdobson.com/2015/07/spidey-wall/
So far, however, I hadn't fully connected the physical (and electronic) wall with the web-browser creations to drive it. This project is hopefully the final link. A fast and reliable web server using REST commands to drive the 1686 LEDs in the Spidey Wall from code running in a browser (say on an iPad while you are playing a game).
The approach taken here results in the ability to control the RGB values of all 1686 LEDs at a rate of 20 frames per second.
A blog post describing the whole thing is here:
http://robdobson.com/2015/08/a-reliable-mbed-webserver/
main.cpp
- Committer:
- Bobty
- Date:
- 2015-08-31
- Revision:
- 4:b521815f2657
- Parent:
- 3:e5ea80fae61d
- Child:
- 5:910909f34907
File content as of revision 4:b521815f2657:
// // LightWall WebServer // // Rob Dobson (C) 2015 // // See http://robdobson.com/2015/07/spidey-wall/ and http://robdobson.com/2015/08/a-reliable-mbed-webserver/ // #include "mbed.h" #include "EthernetInterface.h" #include "RdWebServer.h" #include "DrawingManager.h" #include <string.h> // Web port const int WEBPORT = 80; // Port for web server // Debugging and status RawSerial pc(USBTX, USBRX); DigitalOut led1(LED1); // flashes on command received DigitalOut led2(LED2); // DigitalOut led3(LED3); // DigitalOut led4(LED4); // web server status // System configuration char systemName[20] = "LightWall"; int systemNumLEDS = 20; int systemLEDSSplitPoint = systemNumLEDS; // Drawing Manager DrawingManager drawingManager; // General response string for REST requests char* generalRespStr = "HTTP/1.1 200 OK\r\nConnection: keep-alive\r\nAccess-Control-Allow-Origin: *\r\nAccess-Control-Allow-Methods: POST, GET, OPTIONS\r\nAccess-Control-Allow-Headers:accept, content-type\r\nContent-Length: 0\r\nContent-Type: application/octet-stream\r\n\r\n"; // Get system name - No arguments required char* lightwallGetSystemName(int method, char*cmdStr, char* argStr, char* msgBuffer, int msgLen, int contentLen, unsigned char* pPayload, int payloadLen, int splitPayloadPos) { // Return the system name return systemName; } // Clear LEDS - No arguments required char* lightwallClear(int method, char*cmdStr, char* argStr, char* msgBuffer, int msgLen, int contentLen, unsigned char* pPayload, int payloadLen, int splitPayloadPos) { drawingManager.Clear(); return generalRespStr; } // RawFill - arguments for start LED (e.g. /rawfill?start=0) // - payload of message contains binary data for RGB (1 byte for each) for each LED to be set char* lightwallRawFill(int method, char*cmdStr, char* argStr, char* msgBuffer, int msgLen, int contentLen, unsigned char* pPayload, int payloadLen, int splitPayloadPos) { drawingManager.RawFill(argStr, pPayload, payloadLen, splitPayloadPos); return generalRespStr; } // Fill - arguments for start, numLeds, initial-R/G/B and ending-R/G/B (optional) // - e.g. /fill?start=0&len=100&r1=20&g1=30&b1=50 // - e.g. /fill?start=0&len=100&r1=20&g1=30&b1=50&r2=50&g2=100&b2=23 char* lightwallFill(int method, char*cmdStr, char* argStr, char* msgBuffer, int msgLen, int contentLen, unsigned char* pPayload, int payloadLen, int splitPayloadPos) { drawingManager.Fill(argStr); return generalRespStr; } // ShowLeds - no arguments char* lightwallShowLeds(int method, char*cmdStr, char* argStr, char* msgBuffer, int msgLen, int contentLen, unsigned char* pPayload, int payloadLen, int splitPayloadPos) { // Blink LED led1 = !led1; // Show LEDS drawingManager.ShowLeds(); return generalRespStr; } // Create, configure and run the web server void http_server(void const* arg) { // Init the web server pc.printf("Starting web server\r\n"); char* baseWebFolder = "/sd/"; // should be /sd/ for SDcard files - not used for local file system RdWebServer webServer; // Add commands to handle the home page and favicon webServer.addCommand("", RdWebServerCmdDef::CMD_LOCALFILE, NULL, "index.htm", true); webServer.addCommand("favicon.ico", RdWebServerCmdDef::CMD_LOCALFILE, NULL, NULL, true); // Add the lightwall control commands webServer.addCommand("name", RdWebServerCmdDef::CMD_CALLBACK, &lightwallGetSystemName); webServer.addCommand("clear", RdWebServerCmdDef::CMD_CALLBACK, &lightwallClear); webServer.addCommand("rawfill", RdWebServerCmdDef::CMD_CALLBACK, &lightwallRawFill); webServer.addCommand("fill", RdWebServerCmdDef::CMD_CALLBACK, &lightwallFill); webServer.addCommand("showleds", RdWebServerCmdDef::CMD_CALLBACK, &lightwallShowLeds); // Start the server webServer.init(WEBPORT, &led4, baseWebFolder); webServer.run(); } void getSystemConfig() { printf("LightWall - Configured for "); // Check for a config file on the local file system LocalFileSystem local("local"); FILE* fp = fopen("/local/lights.txt", "r"); if (fp != NULL) { char buf[201]; buf[sizeof(buf)-1] = 0; int nread = fread(buf, 1, sizeof(buf), fp); if (nread > 0 && nread <= sizeof(buf)) { buf[nread] = 0; // Read config details from the file sscanf(buf, "%s %d %d", systemName, &systemNumLEDS, &systemLEDSSplitPoint); } fclose(fp); printf("%s (%d LEDs, Split at %d)", systemName, systemNumLEDS, systemLEDSSplitPoint); printf("\r\n"); } } int main() { // Init pc.baud(115200); pc.printf("Light Wall - Rob Dobson 2015\r\n"); // Get the configuration of the system getSystemConfig(); // Drawing manager controls the LEDs drawingManager.Init(systemNumLEDS, systemLEDSSplitPoint); // Setup ethernet interface char macAddr[6]; mbed_mac_address(macAddr); pc.printf("Ethernet MAC address: %02x:%02x:%02x:%02x:%02x:%02x\r\n", macAddr[0], macAddr[1], macAddr[2], macAddr[3], macAddr[4], macAddr[5]); pc.printf("Connecting to ethernet ...\r\n"); // Init ethernet EthernetInterface::init(); // Using code described here https://developer.mbed.org/questions/1602/How-to-set-the-TCPIP-stack-s-hostname-pr/ // to setName on the ethernet interface EthernetInterface::setName(systemName); // Connect ethernet EthernetInterface::connect(); pc.printf("IP Address: %s HostName %s\r\n", EthernetInterface::getIPAddress(), EthernetInterface::getName()); // Web Server used to run in a thread - but I've found this slows performance a lot as described here: // http://robdobson.com/2015/08/a-reliable-mbed-webserver/ // Fortunately it doesn't matter as the LED code is all interrupt driven // This is the previous code... // Thread httpServer(&http_server, NULL, osPriorityNormal, (DEFAULT_STACK_SIZE * 3)); http_server(""); // Forever - actually it won't even get here as the server has a forever loop in it too while(true) { } }