usbdmx_example.cpp

#include <stdio.h>
extern "C" {
    #include "usbdmx.h"
}
#include <unistd.h>
#include <string.h>
#include <stdlib.h>

void USB_DMX_CALLBACK InterfaceChange(void) {
    printf("Interface cnonfiguration has changed\n");
}

void USB_DMX_CALLBACK InputChange(void) {
    printf("Input has changed\n");
}

void USB_DMX_CALLBACK InputChangeBlock(unsigned char block_number) {
    // printf("Block %d changed\n", block_number);
}

int main(int argc, char *argv[])
{

    int i;
    int res;
    char str[17];
    unsigned char tmp;

    // "InterfaceList" is filled by "GetAllConnectedInterfaces" or "GetAllOpenedInterfaces"
    // It contains the serials of up to 32 connected interfaces. A serial (16 characters) is
    // an array of char with a fixed length of 16, it is not a null terminated string (there is no null-termination)
    TSERIALLIST InterfaceList;

    // "DMX_Out" "DMX_In" are the DMX data buffers
    TDMXArray DMX_Out, DMX_In;

    // You can (optional) register a parameterless function which will be called if at least one interface is configurated in input mode and some input channels have changed
    RegisterInputChangeNotification(&InputChange);

    // Or a function which gets the (32-channel)block-number of the changed channels
    RegisterInputChangeBlockNotification(&InputChangeBlock);

    // Here you get the list of all connected interfaces. If the value (serial) of "0000000000000000" occurs in the list then there are no more interfaces connected
    GetAllConnectedInterfaces(&InterfaceList);

    // With this function you open a link to the specified interface. Also you have to turn over the pointer to your DMX buffers.
    // The first pointer points to the DMX out buffer (PC -> Interface), the second to the DMX in buffer (Interface -> PC)
    // If you don't use either DMX output or DMX input you can set the corresponding pointer to zero.
    // (In this example simply the first interface of the list returned from "GetAllConnectedInterfaces" is opened without testing if there is connected any interface to the PC)

    // Now let's copy over the first SERIAL-Number to a null-terminated string
    str[16] = 0;
    memcpy(str, InterfaceList[0], 16);
    
    printf("SERIAL: %s\n", str);
    printf("VERSION: %d\n", GetDeviceVersion(InterfaceList[0]));

    memset(DMX_In, 0, sizeof(TDMXArray));
    memset(DMX_Out, 0, sizeof(TDMXArray));

    res = OpenLink(InterfaceList[0], &DMX_Out, &DMX_In);

    if(res != 1) {
        printf("Unable to open Interface, did you install the udev-rule?\n");
        exit(1);
    }

    printf("Connected\n");
    sleep(1);

    // If you would call "GetAllOpenedInterfaces" here you'd get a list that contains only one valid serial: InterfaceList[0]

    // Now you can set the mode of the specified interface (a link must be opened).
    // The following modes are allowed:
    // 0: Do nothing - Standby
    // 1: DMX In -> DMX Out
    // 2: PC Out -> DMX Out
    // 3: DMX In + PC Out -> DMX Out
    // 4: DMX In -> PC In
    // 5: DMX In -> DMX Out & DMX In -> PC In
    // 6: PC Out -> DMX Out & DMX In -> PC In
    // 7: DMX In + PC Out -> DMX Out & DMX In -> PC In
    // If you want simply write to the DMX output use mode 2, if you want also read the DMX input use mode 6
    SetInterfaceMode(InterfaceList[0], 6);

    // Now you can write to your DMX out buffer. The dll detects any change and the new values are transmitted to the interface
    for(i=0;i<512;i++) {
        DMX_Out[i] = i;
    }

    while (1) {
        for(i=0;i<512;i++) {
            DMX_Out[i] += 1;
        }

        // Or you can read from the DMX input. If you have registered a function with "RegisterInputChangeNotification" it will be called everytime a channel changes it's value.
        // Every time the function is called up to 32 channels may have changed their value. Please hold the registered function as short as possible (< 1ms execution time)
        tmp = DMX_In[0];
        tmp = DMX_In[1];
        tmp = DMX_In[2];
        tmp = DMX_In[3];
        //... and so on ...

        sleep(1);
        for(i=0;i<512;i++) {
            printf("%3d: %3d/%3d ", i, DMX_Out[i], DMX_In[i]);
            if((i % 6) == 4) {
                printf("\n");
            }
        }
        printf("\n");
    }

    // At the end of the programm you should clean up a little
    CloseLink(InterfaceList[0]);
    UnregisterInputChangeNotification();
    UnregisterInterfaceChangeNotification();

    return 0;
}