Avoided casting-away constness in expected working counter calculation.
/*****************************************************************************
*
* $Id$
*
* Copyright (C) 2007-2009 Florian Pose, Ingenieurgemeinschaft IgH
*
* This file is part of the IgH EtherCAT Master.
*
* The IgH EtherCAT Master is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2, as
* published by the Free Software Foundation.
*
* The IgH EtherCAT Master is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
* Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with the IgH EtherCAT Master; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* ---
*
* The license mentioned above concerns the source code only. Using the
* EtherCAT technology and brand is only permitted in compliance with the
* industrial property and similar rights of Beckhoff Automation GmbH.
*
****************************************************************************/
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <sys/resource.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <time.h>
#include <sys/mman.h>
#include <malloc.h>
/****************************************************************************/
#include "ecrt.h"
/****************************************************************************/
// Application parameters
#define FREQUENCY 1000
#define CLOCK_TO_USE CLOCK_REALTIME
#define MEASURE_TIMING
/****************************************************************************/
#define NSEC_PER_SEC (1000000000L)
#define PERIOD_NS (NSEC_PER_SEC / FREQUENCY)
#define DIFF_NS(A, B) (((B).tv_sec - (A).tv_sec) * NSEC_PER_SEC + \
(B).tv_nsec - (A).tv_nsec)
#define TIMESPEC2NS(T) ((uint64_t) (T).tv_sec * NSEC_PER_SEC + (T).tv_nsec)
/****************************************************************************/
// EtherCAT
static ec_master_t *master = NULL;
static ec_master_state_t master_state = {};
static ec_domain_t *domain1 = NULL;
static ec_domain_state_t domain1_state = {};
/****************************************************************************/
// process data
static uint8_t *domain1_pd = NULL;
#define BusCouplerPos 0, 0
#define DigOutSlavePos 0, 1
#define CounterSlavePos 0, 2
#define Beckhoff_EK1100 0x00000002, 0x044c2c52
#define Beckhoff_EL2008 0x00000002, 0x07d83052
#define IDS_Counter 0x000012ad, 0x05de3052
// offsets for PDO entries
static int off_dig_out;
static int off_counter_in;
static int off_counter_out;
static unsigned int counter = 0;
static unsigned int blink = 0;
static unsigned int sync_ref_counter = 0;
const struct timespec cycletime = {0, PERIOD_NS};
/*****************************************************************************/
struct timespec timespec_add(struct timespec time1, struct timespec time2)
{
struct timespec result;
if ((time1.tv_nsec + time2.tv_nsec) >= NSEC_PER_SEC) {
result.tv_sec = time1.tv_sec + time2.tv_sec + 1;
result.tv_nsec = time1.tv_nsec + time2.tv_nsec - NSEC_PER_SEC;
} else {
result.tv_sec = time1.tv_sec + time2.tv_sec;
result.tv_nsec = time1.tv_nsec + time2.tv_nsec;
}
return result;
}
/*****************************************************************************/
void check_domain1_state(void)
{
ec_domain_state_t ds;
ecrt_domain_state(domain1, &ds);
if (ds.working_counter != domain1_state.working_counter)
printf("Domain1: WC %u.\n", ds.working_counter);
if (ds.wc_state != domain1_state.wc_state)
printf("Domain1: State %u.\n", ds.wc_state);
domain1_state = ds;
}
/*****************************************************************************/
void check_master_state(void)
{
ec_master_state_t ms;
ecrt_master_state(master, &ms);
if (ms.slaves_responding != master_state.slaves_responding)
printf("%u slave(s).\n", ms.slaves_responding);
if (ms.al_states != master_state.al_states)
printf("AL states: 0x%02X.\n", ms.al_states);
if (ms.link_up != master_state.link_up)
printf("Link is %s.\n", ms.link_up ? "up" : "down");
master_state = ms;
}
/****************************************************************************/
void cyclic_task()
{
struct timespec wakeupTime, time;
#ifdef MEASURE_TIMING
struct timespec startTime, endTime, lastStartTime = {};
uint32_t period_ns = 0, exec_ns = 0, latency_ns = 0,
latency_min_ns = 0, latency_max_ns = 0,
period_min_ns = 0, period_max_ns = 0,
exec_min_ns = 0, exec_max_ns = 0;
#endif
// get current time
clock_gettime(CLOCK_TO_USE, &wakeupTime);
while(1) {
wakeupTime = timespec_add(wakeupTime, cycletime);
clock_nanosleep(CLOCK_TO_USE, TIMER_ABSTIME, &wakeupTime, NULL);
#ifdef MEASURE_TIMING
clock_gettime(CLOCK_TO_USE, &startTime);
latency_ns = DIFF_NS(wakeupTime, startTime);
period_ns = DIFF_NS(lastStartTime, startTime);
exec_ns = DIFF_NS(lastStartTime, endTime);
lastStartTime = startTime;
if (latency_ns > latency_max_ns) {
latency_max_ns = latency_ns;
}
if (latency_ns < latency_min_ns) {
latency_min_ns = latency_ns;
}
if (period_ns > period_max_ns) {
period_max_ns = period_ns;
}
if (period_ns < period_min_ns) {
period_min_ns = period_ns;
}
if (exec_ns > exec_max_ns) {
exec_max_ns = exec_ns;
}
if (exec_ns < exec_min_ns) {
exec_min_ns = exec_ns;
}
#endif
// receive process data
ecrt_master_receive(master);
ecrt_domain_process(domain1);
// check process data state (optional)
check_domain1_state();
if (counter) {
counter--;
} else { // do this at 1 Hz
counter = FREQUENCY;
// check for master state (optional)
check_master_state();
#ifdef MEASURE_TIMING
// output timing stats
printf("period %10u ... %10u\n",
period_min_ns, period_max_ns);
printf("exec %10u ... %10u\n",
exec_min_ns, exec_max_ns);
printf("latency %10u ... %10u\n",
latency_min_ns, latency_max_ns);
period_max_ns = 0;
period_min_ns = 0xffffffff;
exec_max_ns = 0;
exec_min_ns = 0xffffffff;
latency_max_ns = 0;
latency_min_ns = 0xffffffff;
#endif
// calculate new process data
blink = !blink;
}
// write process data
EC_WRITE_U8(domain1_pd + off_dig_out, blink ? 0x66 : 0x99);
EC_WRITE_U8(domain1_pd + off_counter_out, blink ? 0x00 : 0x02);
// write application time to master
clock_gettime(CLOCK_TO_USE, &time);
ecrt_master_application_time(master, TIMESPEC2NS(time));
if (sync_ref_counter) {
sync_ref_counter--;
} else {
sync_ref_counter = 1; // sync every cycle
ecrt_master_sync_reference_clock(master);
}
ecrt_master_sync_slave_clocks(master);
// send process data
ecrt_domain_queue(domain1);
ecrt_master_send(master);
#ifdef MEASURE_TIMING
clock_gettime(CLOCK_TO_USE, &endTime);
#endif
}
}
/****************************************************************************/
int main(int argc, char **argv)
{
ec_slave_config_t *sc;
if (mlockall(MCL_CURRENT | MCL_FUTURE) == -1) {
perror("mlockall failed");
return -1;
}
master = ecrt_request_master(0);
if (!master)
return -1;
domain1 = ecrt_master_create_domain(master);
if (!domain1)
return -1;
// Create configuration for bus coupler
sc = ecrt_master_slave_config(master, BusCouplerPos, Beckhoff_EK1100);
if (!sc)
return -1;
if (!(sc = ecrt_master_slave_config(master,
DigOutSlavePos, Beckhoff_EL2008))) {
fprintf(stderr, "Failed to get slave configuration.\n");
return -1;
}
off_dig_out = ecrt_slave_config_reg_pdo_entry(sc,
0x7000, 1, domain1, NULL);
if (off_dig_out < 0)
return -1;
if (!(sc = ecrt_master_slave_config(master,
CounterSlavePos, IDS_Counter))) {
fprintf(stderr, "Failed to get slave configuration.\n");
return -1;
}
off_counter_in = ecrt_slave_config_reg_pdo_entry(sc,
0x6020, 0x11, domain1, NULL);
if (off_counter_in < 0)
return -1;
off_counter_out = ecrt_slave_config_reg_pdo_entry(sc,
0x7020, 1, domain1, NULL);
if (off_counter_out < 0)
return -1;
// configure SYNC signals for this slave
ecrt_slave_config_dc(sc, 0x0700, PERIOD_NS, 4400000, 0, 0);
printf("Activating master...\n");
if (ecrt_master_activate(master))
return -1;
if (!(domain1_pd = ecrt_domain_data(domain1))) {
return -1;
}
pid_t pid = getpid();
if (setpriority(PRIO_PROCESS, pid, -19))
fprintf(stderr, "Warning: Failed to set priority: %s\n",
strerror(errno));
printf("Starting cyclic function.\n");
cyclic_task();
return 0;
}
/****************************************************************************/