Displays a value on an RS display board
Dependencies: EthernetInterface PCA9635 dispBoB mbed-rtos mbed munin-client-lib
Displaying values retrieved from a munin node on an RS display board. Porting this code to work with an alternative display should be trivial, I have also used an mbed application board's LCD to display the values for example.
Hardware
Software
Most of the work is done by libraries that are freely available on mbed.org. The code uses the lwip based EthernetInterface library. The only code I had to write was submit a command to a munin node and parse it's response.
Testing
The software has currently been running for around 2 weeks without any problems. On a previous run it stopped updating after 4 days.
main.cpp@4:186148592f35, 2014-04-11 (annotated)
- Committer:
- PrzemekWirkus
- Date:
- Fri Apr 11 18:13:40 2014 +0000
- Revision:
- 4:186148592f35
- Parent:
- 3:56c6df84e619
- Child:
- 5:5c0288a4e2c7
Small bugfixes.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
PrzemekWirkus | 4:186148592f35 | 1 | #include <string> |
PrzemekWirkus | 4:186148592f35 | 2 | #include <vector> |
PrzemekWirkus | 4:186148592f35 | 3 | #include <sstream> |
stevep | 0:98c94cf86eb8 | 4 | #include "mbed.h" |
stevep | 0:98c94cf86eb8 | 5 | #include "EthernetInterface.h" |
stevep | 0:98c94cf86eb8 | 6 | #include "dispBoB.h" |
PrzemekWirkus | 3:56c6df84e619 | 7 | |
PrzemekWirkus | 3:56c6df84e619 | 8 | namespace { |
PrzemekWirkus | 3:56c6df84e619 | 9 | const char* MUNIN_SERVER_ADDRESS = "172.28.22.45"; |
PrzemekWirkus | 3:56c6df84e619 | 10 | const int MUNIN_SERVER_PORT = 4949; |
PrzemekWirkus | 3:56c6df84e619 | 11 | char CMD_FETCH_USERS[] = "fetch users\n"; |
PrzemekWirkus | 3:56c6df84e619 | 12 | } |
stevep | 0:98c94cf86eb8 | 13 | |
stevep | 0:98c94cf86eb8 | 14 | |
PrzemekWirkus | 3:56c6df84e619 | 15 | class MuninDisplay { |
PrzemekWirkus | 3:56c6df84e619 | 16 | public: |
PrzemekWirkus | 4:186148592f35 | 17 | MuninDisplay() : bob_display(p28, p27, p26) { |
PrzemekWirkus | 4:186148592f35 | 18 | bob_display.cls(); |
PrzemekWirkus | 3:56c6df84e619 | 19 | } |
PrzemekWirkus | 3:56c6df84e619 | 20 | |
PrzemekWirkus | 3:56c6df84e619 | 21 | void lcd_print_str(const char *str) { |
PrzemekWirkus | 4:186148592f35 | 22 | bob_display.cls(); |
PrzemekWirkus | 4:186148592f35 | 23 | bob_display.printf("%s\n", str); |
PrzemekWirkus | 3:56c6df84e619 | 24 | } |
PrzemekWirkus | 3:56c6df84e619 | 25 | |
PrzemekWirkus | 3:56c6df84e619 | 26 | void dhcp_connection() { |
PrzemekWirkus | 3:56c6df84e619 | 27 | printf("DHCP: Connecting ... "); |
PrzemekWirkus | 3:56c6df84e619 | 28 | eth.init(); //Use DHCP |
PrzemekWirkus | 3:56c6df84e619 | 29 | eth.connect(); |
PrzemekWirkus | 3:56c6df84e619 | 30 | printf("%s\r\n", eth.getIPAddress()); |
PrzemekWirkus | 3:56c6df84e619 | 31 | } |
PrzemekWirkus | 3:56c6df84e619 | 32 | |
PrzemekWirkus | 3:56c6df84e619 | 33 | int socket_connection() { |
PrzemekWirkus | 3:56c6df84e619 | 34 | printf("TCP: Connecting ... "); |
PrzemekWirkus | 3:56c6df84e619 | 35 | int ret = socket.connect(MUNIN_SERVER_ADDRESS, MUNIN_SERVER_PORT) < 0; |
PrzemekWirkus | 3:56c6df84e619 | 36 | printf("[OK]\r\n"); |
PrzemekWirkus | 3:56c6df84e619 | 37 | return ret; |
PrzemekWirkus | 3:56c6df84e619 | 38 | } |
PrzemekWirkus | 3:56c6df84e619 | 39 | |
PrzemekWirkus | 4:186148592f35 | 40 | void socket_close() { |
PrzemekWirkus | 3:56c6df84e619 | 41 | socket.close(); |
PrzemekWirkus | 3:56c6df84e619 | 42 | } |
stevep | 0:98c94cf86eb8 | 43 | |
PrzemekWirkus | 3:56c6df84e619 | 44 | int socket_recv() { |
PrzemekWirkus | 3:56c6df84e619 | 45 | const int n = socket.receive(buf, sizeof(buf) - 1); |
PrzemekWirkus | 3:56c6df84e619 | 46 | if (n > 0) { |
PrzemekWirkus | 3:56c6df84e619 | 47 | buf[n] = '\0'; |
PrzemekWirkus | 3:56c6df84e619 | 48 | printf("RECV: %s\r\n", buf); |
PrzemekWirkus | 3:56c6df84e619 | 49 | } |
PrzemekWirkus | 3:56c6df84e619 | 50 | return n; |
PrzemekWirkus | 3:56c6df84e619 | 51 | } |
PrzemekWirkus | 3:56c6df84e619 | 52 | |
PrzemekWirkus | 3:56c6df84e619 | 53 | int socket_recv_all() { |
PrzemekWirkus | 3:56c6df84e619 | 54 | const int n = socket.receive_all(buf, sizeof(buf) - 1); |
PrzemekWirkus | 3:56c6df84e619 | 55 | if (n > 0) { |
PrzemekWirkus | 3:56c6df84e619 | 56 | buf[n] = '\0'; |
PrzemekWirkus | 3:56c6df84e619 | 57 | printf("RECV: %s\r\n", buf); |
PrzemekWirkus | 3:56c6df84e619 | 58 | } |
PrzemekWirkus | 3:56c6df84e619 | 59 | return n; |
PrzemekWirkus | 3:56c6df84e619 | 60 | } |
PrzemekWirkus | 3:56c6df84e619 | 61 | |
PrzemekWirkus | 3:56c6df84e619 | 62 | int socket_send(char *cmd, const int cmd_size) { |
PrzemekWirkus | 3:56c6df84e619 | 63 | const int n = socket.send(cmd, cmd_size - 1); |
PrzemekWirkus | 3:56c6df84e619 | 64 | return n; |
PrzemekWirkus | 3:56c6df84e619 | 65 | } |
stevep | 0:98c94cf86eb8 | 66 | |
PrzemekWirkus | 3:56c6df84e619 | 67 | int get_param_value(std::string param_name) { |
PrzemekWirkus | 3:56c6df84e619 | 68 | std::vector<std::string> s = explode(std::string(buf), '\n'); |
PrzemekWirkus | 3:56c6df84e619 | 69 | |
PrzemekWirkus | 3:56c6df84e619 | 70 | for (std::vector<std::string>::iterator it = s.begin(); it != s.end(); ++it) { |
PrzemekWirkus | 3:56c6df84e619 | 71 | std::string ¶m = *it; |
PrzemekWirkus | 3:56c6df84e619 | 72 | printf("PARAM_RECV: %s\r\n", param.c_str()); |
PrzemekWirkus | 3:56c6df84e619 | 73 | if (!param.compare(0, param_name.size(), param_name)) { |
PrzemekWirkus | 3:56c6df84e619 | 74 | printf("PARAM_FOUND: %s is '%s' \r\n", param.c_str(), param_name.c_str()); |
PrzemekWirkus | 3:56c6df84e619 | 75 | std::vector<std::string> name_value = explode(param, ' '); |
PrzemekWirkus | 3:56c6df84e619 | 76 | if (name_value.size() == 2) { |
PrzemekWirkus | 3:56c6df84e619 | 77 | const int val = atoi(name_value[1].c_str()); |
PrzemekWirkus | 4:186148592f35 | 78 | bob_display.cls(); |
PrzemekWirkus | 4:186148592f35 | 79 | bob_display.printf(" %s\n", name_value[1].c_str()); |
PrzemekWirkus | 3:56c6df84e619 | 80 | printf("DISPLAYING: %s\r\n", name_value[1].c_str()); |
PrzemekWirkus | 3:56c6df84e619 | 81 | return val; |
PrzemekWirkus | 3:56c6df84e619 | 82 | } |
PrzemekWirkus | 3:56c6df84e619 | 83 | } |
PrzemekWirkus | 3:56c6df84e619 | 84 | } |
PrzemekWirkus | 3:56c6df84e619 | 85 | return 0; |
PrzemekWirkus | 3:56c6df84e619 | 86 | } |
PrzemekWirkus | 3:56c6df84e619 | 87 | |
PrzemekWirkus | 3:56c6df84e619 | 88 | protected: |
stevep | 0:98c94cf86eb8 | 89 | EthernetInterface eth; |
stevep | 0:98c94cf86eb8 | 90 | TCPSocketConnection socket; |
PrzemekWirkus | 4:186148592f35 | 91 | dispBoB bob_display; |
stevep | 0:98c94cf86eb8 | 92 | char buf[256]; |
stevep | 0:98c94cf86eb8 | 93 | |
PrzemekWirkus | 3:56c6df84e619 | 94 | std::vector<std::string> explode(std::string const &s, char delim) |
PrzemekWirkus | 3:56c6df84e619 | 95 | { |
PrzemekWirkus | 3:56c6df84e619 | 96 | std::vector<std::string> result; |
PrzemekWirkus | 3:56c6df84e619 | 97 | std::istringstream iss(s); |
PrzemekWirkus | 3:56c6df84e619 | 98 | for (std::string token; std::getline(iss, token, delim); ) { |
PrzemekWirkus | 3:56c6df84e619 | 99 | result.push_back(token); |
PrzemekWirkus | 3:56c6df84e619 | 100 | } |
PrzemekWirkus | 3:56c6df84e619 | 101 | return result; |
PrzemekWirkus | 3:56c6df84e619 | 102 | } |
PrzemekWirkus | 3:56c6df84e619 | 103 | }; |
stevep | 0:98c94cf86eb8 | 104 | |
PrzemekWirkus | 3:56c6df84e619 | 105 | int main() { |
PrzemekWirkus | 3:56c6df84e619 | 106 | MuninDisplay munin_lcd; |
PrzemekWirkus | 3:56c6df84e619 | 107 | munin_lcd.dhcp_connection(); // DHCP connection |
PrzemekWirkus | 3:56c6df84e619 | 108 | |
PrzemekWirkus | 3:56c6df84e619 | 109 | while(true) { |
PrzemekWirkus | 3:56c6df84e619 | 110 | while (munin_lcd.socket_connection() < 0) { |
stevep | 0:98c94cf86eb8 | 111 | wait(1); |
stevep | 0:98c94cf86eb8 | 112 | } |
stevep | 0:98c94cf86eb8 | 113 | |
PrzemekWirkus | 3:56c6df84e619 | 114 | munin_lcd.socket_recv(); |
PrzemekWirkus | 3:56c6df84e619 | 115 | munin_lcd.socket_send(CMD_FETCH_USERS, sizeof(CMD_FETCH_USERS)); |
PrzemekWirkus | 3:56c6df84e619 | 116 | munin_lcd.socket_recv_all(); |
PrzemekWirkus | 3:56c6df84e619 | 117 | munin_lcd.get_param_value("usercount.value"); |
stevep | 0:98c94cf86eb8 | 118 | |
PrzemekWirkus | 3:56c6df84e619 | 119 | munin_lcd.socket_close(); |
PrzemekWirkus | 3:56c6df84e619 | 120 | wait(3); |
stevep | 0:98c94cf86eb8 | 121 | } |
PrzemekWirkus | 3:56c6df84e619 | 122 | } |