Stephen Paulger / Mbed 2 deprecated munin-display-board

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@2:b4e81333dfef, 2014-04-11 (annotated)

Committer:
stevep
Date:
Fri Apr 11 10:52:21 2014 +0000
Revision:
2:b4e81333dfef
Parent:
0:98c94cf86eb8
Child:
3:56c6df84e619
Replace DisplayBoard printfs with serial printfs.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
stevep 0:98c94cf86eb8 1 #include "mbed.h"
stevep 0:98c94cf86eb8 2 #include "EthernetInterface.h"
stevep 0:98c94cf86eb8 3 #include "dispBoB.h"
stevep 0:98c94cf86eb8 4
stevep 0:98c94cf86eb8 5
stevep 0:98c94cf86eb8 6 const char* MUNIN_SERVER_ADDRESS = "172.28.22.45";
stevep 0:98c94cf86eb8 7 const int MUNIN_SERVER_PORT = 4949;
stevep 0:98c94cf86eb8 8 char cmd[] = "fetch users\n";
stevep 0:98c94cf86eb8 9
stevep 0:98c94cf86eb8 10 dispBoB db(p28, p27, p26);
stevep 0:98c94cf86eb8 11
stevep 0:98c94cf86eb8 12 int main() {
stevep 0:98c94cf86eb8 13 EthernetInterface eth;
stevep 0:98c94cf86eb8 14 TCPSocketConnection socket;
stevep 0:98c94cf86eb8 15
stevep 0:98c94cf86eb8 16 char buf[256];
stevep 0:98c94cf86eb8 17 char *value;
stevep 0:98c94cf86eb8 18 int n, count, wd=0, curval=0;
stevep 0:98c94cf86eb8 19
stevep 2:b4e81333dfef 20 printf("DHCPing\n");
stevep 0:98c94cf86eb8 21
stevep 0:98c94cf86eb8 22 eth.init(); //Use DHCP
stevep 0:98c94cf86eb8 23 eth.connect();
stevep 0:98c94cf86eb8 24
stevep 2:b4e81333dfef 25 printf("IP: %s\n", eth.getIPAddress());
stevep 0:98c94cf86eb8 26
stevep 0:98c94cf86eb8 27 while(1) {
stevep 0:98c94cf86eb8 28 wd++;
stevep 0:98c94cf86eb8 29 while (socket.connect(MUNIN_SERVER_ADDRESS, MUNIN_SERVER_PORT) < 0) {
stevep 2:b4e81333dfef 30 printf("Cnct");
stevep 0:98c94cf86eb8 31 wait(1);
stevep 0:98c94cf86eb8 32 }
stevep 0:98c94cf86eb8 33
stevep 0:98c94cf86eb8 34 n = socket.receive(buf, 256);
stevep 0:98c94cf86eb8 35 buf[n] = '\0';
stevep 0:98c94cf86eb8 36 n = socket.send(cmd, sizeof(cmd) - 1);
stevep 0:98c94cf86eb8 37
stevep 0:98c94cf86eb8 38 buf[0] = '\0';
stevep 0:98c94cf86eb8 39 n = socket.receive_all(buf, 256);
stevep 0:98c94cf86eb8 40 buf[n] = '\0';
stevep 0:98c94cf86eb8 41
stevep 0:98c94cf86eb8 42 count = 0;
stevep 0:98c94cf86eb8 43
stevep 0:98c94cf86eb8 44 for (int i=0; i < sizeof(buf); i++) {
stevep 0:98c94cf86eb8 45 if (buf[i] == '\n' && (i == 0 || buf[i-1] != '.')) {
stevep 0:98c94cf86eb8 46 count++;
stevep 0:98c94cf86eb8 47 }
stevep 0:98c94cf86eb8 48 }
stevep 0:98c94cf86eb8 49
stevep 0:98c94cf86eb8 50 char* ptr = buf;
stevep 0:98c94cf86eb8 51
stevep 0:98c94cf86eb8 52 printf("%s\n", buf);
stevep 0:98c94cf86eb8 53
stevep 0:98c94cf86eb8 54 for (int i=0; i < count; i++) {
stevep 0:98c94cf86eb8 55 char *space = strstr(ptr, " ");
stevep 0:98c94cf86eb8 56 value = space + 1;
stevep 0:98c94cf86eb8 57 char *name;
stevep 0:98c94cf86eb8 58
stevep 0:98c94cf86eb8 59 *space = 0;
stevep 0:98c94cf86eb8 60 name = ptr;
stevep 0:98c94cf86eb8 61
stevep 0:98c94cf86eb8 62 ptr = value;
stevep 0:98c94cf86eb8 63 ptr = strstr(ptr, "\n");
stevep 0:98c94cf86eb8 64 *ptr = 0;
stevep 0:98c94cf86eb8 65
stevep 0:98c94cf86eb8 66 if (strncmp(name, "usercount.value", 15) == 0) {
stevep 0:98c94cf86eb8 67 printf("%s\n", value);
stevep 0:98c94cf86eb8 68 if (curval < atoi(value)) {
stevep 0:98c94cf86eb8 69 curval = atoi(value);
stevep 0:98c94cf86eb8 70 db.cls();
stevep 0:98c94cf86eb8 71 db.printf(" %s\n", value);
stevep 0:98c94cf86eb8 72 }
stevep 0:98c94cf86eb8 73 break;
stevep 0:98c94cf86eb8 74 }
stevep 0:98c94cf86eb8 75
stevep 0:98c94cf86eb8 76 ptr++;
stevep 0:98c94cf86eb8 77 }
stevep 0:98c94cf86eb8 78
stevep 0:98c94cf86eb8 79 socket.close();
stevep 0:98c94cf86eb8 80 wait(10);
stevep 0:98c94cf86eb8 81 }
stevep 0:98c94cf86eb8 82 }