/******************************************************************************
*
* $Id$
*
* Copyright (C) 2011 IgH Andreas Stewering-Bone
* 2012 Florian Pose <fp@igh-essen.com>
*
* 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, see <http://www.gnu.org/licenses/>.
*
* ---
*
* 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 <sched.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <signal.h>
#include <rtai_lxrt.h>
#include <rtdm/rtdm.h>
#include "ecrt.h"
#define rt_printf(X, Y)
#define NSEC_PER_SEC 1000000000
RT_TASK *task;
static unsigned int cycle_ns = 1000000; /* 1 ms */
static int run = 1;
/****************************************************************************/
// 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 = {};
static uint8_t *domain1_pd = NULL;
static ec_slave_config_t *sc_dig_out_01 = NULL;
/****************************************************************************/
// EtherCAT distributed clock variables
#define DC_FILTER_CNT 1024
#define SYNC_MASTER_TO_REF 1
static uint64_t dc_start_time_ns = 0LL;
static uint64_t dc_time_ns = 0;
#if SYNC_MASTER_TO_REF
static uint8_t dc_started = 0;
static int32_t dc_diff_ns = 0;
static int32_t prev_dc_diff_ns = 0;
static int64_t dc_diff_total_ns = 0LL;
static int64_t dc_delta_total_ns = 0LL;
static int dc_filter_idx = 0;
static int64_t dc_adjust_ns;
#endif
static int64_t system_time_base = 0LL;
static uint64_t wakeup_time = 0LL;
static uint64_t overruns = 0LL;
/****************************************************************************/
// process data
#define BusCoupler01_Pos 0, 0
#define DigOutSlave01_Pos 0, 1
#define Beckhoff_EK1100 0x00000002, 0x044c2c52
#define Beckhoff_EL2004 0x00000002, 0x07d43052
// offsets for PDO entries
static unsigned int off_dig_out0 = 0;
// process data
const static ec_pdo_entry_reg_t domain1_regs[] = {
{DigOutSlave01_Pos, Beckhoff_EL2004, 0x7000, 0x01, &off_dig_out0, NULL},
{}
};
/****************************************************************************/
/* Slave 1, "EL2004"
* Vendor ID: 0x00000002
* Product code: 0x07d43052
* Revision number: 0x00100000
*/
ec_pdo_entry_info_t slave_1_pdo_entries[] = {
{0x7000, 0x01, 1}, /* Output */
{0x7010, 0x01, 1}, /* Output */
{0x7020, 0x01, 1}, /* Output */
{0x7030, 0x01, 1}, /* Output */
};
ec_pdo_info_t slave_1_pdos[] = {
{0x1600, 1, slave_1_pdo_entries + 0}, /* Channel 1 */
{0x1601, 1, slave_1_pdo_entries + 1}, /* Channel 2 */
{0x1602, 1, slave_1_pdo_entries + 2}, /* Channel 3 */
{0x1603, 1, slave_1_pdo_entries + 3}, /* Channel 4 */
};
ec_sync_info_t slave_1_syncs[] = {
{0, EC_DIR_OUTPUT, 4, slave_1_pdos + 0, EC_WD_ENABLE},
{0xff}
};
/*****************************************************************************
* Realtime task
****************************************************************************/
/** Get the time in ns for the current cpu, adjusted by system_time_base.
*
* \attention Rather than calling rt_get_time_ns() directly, all application
* time calls should use this method instead.
*
* \ret The time in ns.
*/
uint64_t system_time_ns(void)
{
RTIME time = rt_get_time_ns();
if (system_time_base > time) {
rt_printk("%s() error: system_time_base greater than"
" system time (system_time_base: %lld, time: %llu\n",
__func__, system_time_base, time);
return time;
}
else {
return time - system_time_base;
}
}
/****************************************************************************/
/** Convert system time to RTAI time in counts (via the system_time_base).
*/
RTIME system2count(
uint64_t time
)
{
RTIME ret;
if ((system_time_base < 0) &&
((uint64_t) (-system_time_base) > time)) {
rt_printk("%s() error: system_time_base less than"
" system time (system_time_base: %lld, time: %llu\n",
__func__, system_time_base, time);
ret = time;
}
else {
ret = time + system_time_base;
}
return nano2count(ret);
}
/*****************************************************************************/
/** Synchronise the distributed clocks
*/
void sync_distributed_clocks(void)
{
#if SYNC_MASTER_TO_REF
uint32_t ref_time = 0;
uint64_t prev_app_time = dc_time_ns;
#endif
dc_time_ns = system_time_ns();
// set master time in nano-seconds
ecrt_master_application_time(master, dc_time_ns);
#if SYNC_MASTER_TO_REF
// get reference clock time to synchronize master cycle
ecrt_master_reference_clock_time(master, &ref_time);
dc_diff_ns = (uint32_t) prev_app_time - ref_time;
#else
// sync reference clock to master
ecrt_master_sync_reference_clock(master);
#endif
// call to sync slaves to ref slave
ecrt_master_sync_slave_clocks(master);
}
/*****************************************************************************/
/** Return the sign of a number
*
* ie -1 for -ve value, 0 for 0, +1 for +ve value
*
* \retval the sign of the value
*/
#define sign(val) \
({ typeof (val) _val = (val); \
((_val > 0) - (_val < 0)); })
/*****************************************************************************/
/** Update the master time based on ref slaves time diff
*
* called after the ethercat frame is sent to avoid time jitter in
* sync_distributed_clocks()
*/
void update_master_clock(void)
{
#if SYNC_MASTER_TO_REF
// calc drift (via un-normalised time diff)
int32_t delta = dc_diff_ns - prev_dc_diff_ns;
prev_dc_diff_ns = dc_diff_ns;
// normalise the time diff
dc_diff_ns =
((dc_diff_ns + (cycle_ns / 2)) % cycle_ns) - (cycle_ns / 2);
// only update if primary master
if (dc_started) {
// add to totals
dc_diff_total_ns += dc_diff_ns;
dc_delta_total_ns += delta;
dc_filter_idx++;
if (dc_filter_idx >= DC_FILTER_CNT) {
// add rounded delta average
dc_adjust_ns +=
((dc_delta_total_ns + (DC_FILTER_CNT / 2)) / DC_FILTER_CNT);
// and add adjustment for general diff (to pull in drift)
dc_adjust_ns += sign(dc_diff_total_ns / DC_FILTER_CNT);
// limit crazy numbers (0.1% of std cycle time)
if (dc_adjust_ns < -1000) {
dc_adjust_ns = -1000;
}
if (dc_adjust_ns > 1000) {
dc_adjust_ns = 1000;
}
// reset
dc_diff_total_ns = 0LL;
dc_delta_total_ns = 0LL;
dc_filter_idx = 0;
}
// add cycles adjustment to time base (including a spot adjustment)
system_time_base += dc_adjust_ns + sign(dc_diff_ns);
}
else {
dc_started = (dc_diff_ns != 0);
if (dc_started) {
// output first diff
rt_printk("First master diff: %d.\n", dc_diff_ns);
// record the time of this initial cycle
dc_start_time_ns = dc_time_ns;
}
}
#endif
}
/****************************************************************************/
void rt_check_domain_state(void)
{
ec_domain_state_t ds = {};
ecrt_domain_state(domain1, &ds);
if (ds.working_counter != domain1_state.working_counter) {
rt_printf("Domain1: WC %u.\n", ds.working_counter);
}
if (ds.wc_state != domain1_state.wc_state) {
rt_printf("Domain1: State %u.\n", ds.wc_state);
}
domain1_state = ds;
}
/****************************************************************************/
void rt_check_master_state(void)
{
ec_master_state_t ms;
ecrt_master_state(master, &ms);
if (ms.slaves_responding != master_state.slaves_responding) {
rt_printf("%u slave(s).\n", ms.slaves_responding);
}
if (ms.al_states != master_state.al_states) {
rt_printf("AL states: 0x%02X.\n", ms.al_states);
}
if (ms.link_up != master_state.link_up) {
rt_printf("Link is %s.\n", ms.link_up ? "up" : "down");
}
master_state = ms;
}
/****************************************************************************/
/** Wait for the next period
*/
void wait_period(void)
{
while (1)
{
RTIME wakeup_count = system2count(wakeup_time);
RTIME current_count = rt_get_time();
if ((wakeup_count < current_count)
|| (wakeup_count > current_count + (50 * cycle_ns))) {
rt_printk("%s(): unexpected wake time!\n", __func__);
}
switch (rt_sleep_until(wakeup_count)) {
case RTE_UNBLKD:
rt_printk("rt_sleep_until(): RTE_UNBLKD\n");
continue;
case RTE_TMROVRN:
rt_printk("rt_sleep_until(): RTE_TMROVRN\n");
overruns++;
if (overruns % 100 == 0) {
// in case wake time is broken ensure other processes get
// some time slice (and error messages can get displayed)
rt_sleep(cycle_ns / 100);
}
break;
default:
break;
}
// done if we got to here
break;
}
// calc next wake time (in sys time)
wakeup_time += cycle_ns;
}
/****************************************************************************/
void my_cyclic(void)
{
int cycle_counter = 0;
unsigned int blink = 0;
// oneshot mode to allow adjustable wake time
rt_set_oneshot_mode();
// set first wake time in a few cycles
wakeup_time = system_time_ns() + 10 * cycle_ns;
// start the timer
start_rt_timer(nano2count(cycle_ns));
rt_make_hard_real_time();
while (run) {
// wait for next period (using adjustable system time)
wait_period();
cycle_counter++;
if (!run) {
break;
}
// receive EtherCAT
ecrt_master_receive(master);
ecrt_domain_process(domain1);
rt_check_domain_state();
if (!(cycle_counter % 1000)) {
rt_check_master_state();
}
if (!(cycle_counter % 200)) {
blink = !blink;
}
EC_WRITE_U8(domain1_pd + off_dig_out0, blink ? 0x00 : 0x0F);
// queue process data
ecrt_domain_queue(domain1);
// sync distributed clock just before master_send to set
// most accurate master clock time
sync_distributed_clocks();
// send EtherCAT data
ecrt_master_send(master);
// update the master clock
// Note: called after ecrt_master_send() to reduce time
// jitter in the sync_distributed_clocks() call
update_master_clock();
}
rt_make_soft_real_time();
stop_rt_timer();
}
/****************************************************************************
* Signal handler
***************************************************************************/
void signal_handler(int sig)
{
run = 0;
}
/****************************************************************************
* Main function
***************************************************************************/
int main(int argc, char *argv[])
{
ec_slave_config_t *sc_ek1100;
int ret;
signal(SIGTERM, signal_handler);
signal(SIGINT, signal_handler);
mlockall(MCL_CURRENT | MCL_FUTURE);
printf("Requesting master...\n");
master = ecrt_request_master(0);
if (!master) {
return -1;
}
domain1 = ecrt_master_create_domain(master);
if (!domain1) {
return -1;
}
printf("Creating slave configurations...\n");
// Create configuration for bus coupler
sc_ek1100 =
ecrt_master_slave_config(master, BusCoupler01_Pos, Beckhoff_EK1100);
if (!sc_ek1100) {
return -1;
}
sc_dig_out_01 =
ecrt_master_slave_config(master, DigOutSlave01_Pos, Beckhoff_EL2004);
if (!sc_dig_out_01) {
fprintf(stderr, "Failed to get slave configuration.\n");
return -1;
}
if (ecrt_slave_config_pdos(sc_dig_out_01, EC_END, slave_1_syncs)) {
fprintf(stderr, "Failed to configure PDOs.\n");
return -1;
}
if (ecrt_domain_reg_pdo_entry_list(domain1, domain1_regs)) {
fprintf(stderr, "PDO entry registration failed!\n");
return -1;
}
/* Set the initial master time and select a slave to use as the DC
* reference clock, otherwise pass NULL to auto select the first capable
* slave. Note: This can be used whether the master or the ref slave will
* be used as the systems master DC clock.
*/
dc_start_time_ns = system_time_ns();
dc_time_ns = dc_start_time_ns;
ecrt_master_application_time(master, dc_start_time_ns);
ret = ecrt_master_select_reference_clock(master, sc_ek1100);
if (ret < 0) {
fprintf(stderr, "Failed to select reference clock: %s\n",
strerror(-ret));
return ret;
}
printf("Activating master...\n");
if (ecrt_master_activate(master)) {
return -1;
}
if (!(domain1_pd = ecrt_domain_data(domain1))) {
fprintf(stderr, "Failed to get domain data pointer.\n");
return -1;
}
/* Create cyclic RT-thread */
struct sched_param param;
param.sched_priority = sched_get_priority_max(SCHED_FIFO) - 1;
if (sched_setscheduler(0, SCHED_FIFO, ¶m) == -1) {
puts("ERROR IN SETTING THE SCHEDULER");
perror("errno");
return -1;
}
task = rt_task_init(nam2num("ec_rtai_rtdm_example"),
0 /* priority */, 0 /* stack size */, 0 /* msg size */);
my_cyclic();
rt_task_delete(task);
printf("End of Program\n");
ecrt_release_master(master);
return 0;
}
/****************************************************************************/