|
DCTag SDK
1.2.1
Copyright © 1983-2016 Advantech Co., Ltd.
|
dc_tag_update.c
This is an example of how to add and update tags in the DataCenter. This example will add three tags into the DataCenter: tag_1, tag_2 and tag_3. The tag_1 and the tag_2 are initialized with a random value, and added up every 10 seconds. The tag_3 is calculated by tag_1 + tag_2.
#include <memory.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>
#include "DCTag.h"
#define MAX_TAG_COUNT 3
DC_TAG tag_data[ MAX_TAG_COUNT ];
DC_TAG_HANDLE tag_added[ MAX_TAG_COUNT ];
DC_TAG_HANDLE tag_opened[ MAX_TAG_COUNT ];
static uint32_t get_tick_count ( void )
{
uint32_t tick;
struct timespec tp = { 0, 0 };
clock_gettime( CLOCK_MONOTONIC, &tp );
tick = tp.tv_sec * 1000 + tp.tv_nsec / ( 1000 * 1000 );
return tick;
}
static int on_read_tag (
DC_TAG_HANDLE tag_handles[],
void * tag_context[],
DC_TAG tag_values[],
uint32_t count,
void * user_context )
{
uint32_t i;
printf( "%s: count = %u\n", __func__, count );
for ( i = 0; i < count; i++ )
{
if ( tag == &tag_data[ 0 ] )
{
}
else if ( tag == &tag_data[ 1 ] )
{
printf( "%s: tag_2 = %lf\n", __func__, tag->value );
}
else if ( tag == &tag_data[ 2 ] )
{
printf( "%s: tag_3 = %lf\n", __func__, tag->value );
}
else
{
printf( "%s: unexpected tag context %p\n", __func__, tag );
continue;
}
tag_values[ i ] = *tag;
}
return 0;
}
static void recalc_tag_3 ( struct timeval * tv )
{
double value;
if ( value != tag_data[ 2 ].value )
{
tag_data[ 2 ].value = value;
tag_data[ 2 ].time = tv->tv_sec;
tag_data[ 2 ].usec = tv->tv_usec;
dc_tag_update( &tag_added[ 2 ], &tag_data[ 2 ], 1 );
}
}
static int on_write_tag (
DC_TAG_HANDLE tag_handles[],
void * tag_context[],
double tag_values[],
uint32_t count,
void * user_context )
{
struct timeval tv;
struct timezone tz;
uint32_t i;
printf( "%s: %u count = %u\n", __func__, get_tick_count(), count );
gettimeofday( &tv, &tz );
for ( i = 0; i < count; i++ )
{
if ( tag == &tag_data[ 0 ] )
{
printf( "write tag_1 with %lf!\n", tag_values[ i ] );
if ( tag->value != tag_values[ i ] )
{
tag->value = tag_values[ i ];
tag->time = tv.tv_sec;
tag->usec = tv.tv_usec;
recalc_tag_3( &tv );
dc_tag_update( &tag_handles[ 0 ], tag, 1 );
}
}
else if ( tag == &tag_data[ 1 ] )
{
printf( "write tag_2 with %lf!\n", tag_values[ i ] );
if ( tag->value != tag_values[ i ] )
{
tag->value = tag_values[ i ];
tag->time = tv.tv_sec;
tag->usec = tv.tv_usec;
recalc_tag_3( &tv );
dc_tag_update( &tag_handles[ 1 ], tag, 1 );
}
}
else if ( tag == &tag_data[ 2 ] )
{
printf( "Writing to tag_3 is not allowed!\n" );
}
}
printf( "%s: %u finished\n", __func__, get_tick_count() );
return 0;
}
static int on_update_tag (
DC_TAG_HANDLE tag_handle,
void * tag_context,
DC_TAG * tag_value,
void * user_context )
{
if ( tag_handle == tag_opened[ 0 ] )
{
printf( "%s: tag_1 = %lf\n", __func__, tag_value->value );
}
else if ( tag_handle == tag_opened[ 1 ] )
{
printf( "%s: tag_2 = %lf\n", __func__, tag_value->value );
}
else if ( tag_handle == tag_opened[ 2 ] )
{
printf( "%s: tag_3 = %lf\n", __func__, tag_value->value );
}
else
{
printf( "%s: unexpected tag handle %p\n", __func__, tag_handle );
return -1;
}
return 0;
}
int main ( int argc, char * argv[] )
{
DC_TAG_CALLBACK callback;
char tag_name[ 100 ];
struct timeval tv;
struct timezone tz;
int rc;
int i;
srand( time( NULL ) );
callback.read_tag = on_read_tag;
callback.write_tag = on_write_tag;
callback.update_tag = on_update_tag;
// initialize the DCTag SDK
rc = dc_tag_init( MAX_TAG_COUNT * 2, &callback, NULL );
if ( rc != 0 )
{
printf( "dc_tag_init failed! error = %d\n", rc );
return -1;
}
gettimeofday( &tv, &tz );
// prepare the tag handles
for ( i = 0; i < MAX_TAG_COUNT; i++ )
{
sprintf( tag_name, "tag_%d", i + 1 );
tag_data[ i ].value = rand() % 10;
tag_data[ i ].quality = 0;
tag_data[ i ].time = tv.tv_sec;
tag_data[ i ].usec = tv.tv_usec;
printf( "%s = %lf\n", tag_name, tag_data[ i ].value );
tag_added[ i ] = dc_tag_add(
tag_name,
&tag_data[ i ] );
if ( NULL == tag_added[ i ] )
{
printf( "fail to add tag: %s\n", tag_name );
return -2;
}
tag_opened[ i ] = dc_tag_open( tag_name, NULL );
if ( NULL == tag_opened[ i ] )
{
printf( "fail to open tag: %s\n", tag_name );
return -3;
}
}
while ( 1 )
{
sleep( 10 );
gettimeofday( &tv, &tz );
for ( i = 0; i < 2; i++ )
{
tag_data[ i ].value += 1;
tag_data[ i ].time = tv.tv_sec;
tag_data[ i ].usec = tv.tv_usec;
}
rc = dc_tag_update( tag_added, tag_data, 2 );
if ( rc != 0 )
{
printf( "dc_tag_update failed! error = %d\n", rc );
}
recalc_tag_3( &tv );
}
// close tag handles
for ( i = 0; i < MAX_TAG_COUNT; i++ )
{
dc_tag_remove( tag_added[ i ] );
}
// uninitialize the SDK
return 0;
}
Generated on Thu May 19 2016 14:18:17 for DCTag SDK by
1.8.11