Minor changes in minimal example.
/******************************************************************************
*
* RTAI sample for the IgH EtherCAT master.
*
* $Id$
*
* Copyright (C) 2006 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
* as published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* 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 right to use EtherCAT Technology is granted and comes free of
* charge under condition of compatibility of product made by
* Licensee. People intending to distribute/sell products based on the
* code, have to sign an agreement to guarantee that products using
* software based on IgH EtherCAT master stay compatible with the actual
* EtherCAT specification (which are released themselves as an open
* standard) as the (only) precondition to have the right to use EtherCAT
* Technology, IP and trade marks.
*
*****************************************************************************/
// Linux
#include <linux/module.h>
// RTAI
#include "rtai_sched.h"
#include "rtai_sem.h"
// EtherCAT
#include "../../include/ecrt.h"
#include "../../include/ecdb.h"
/*****************************************************************************/
// RTAI task frequency in Hz
#define FREQUENCY 10000
#define INHIBIT_TIME 20
#define TIMERTICKS (1000000000 / FREQUENCY)
/*****************************************************************************/
// RTAI
RT_TASK task;
SEM master_sem;
cycles_t t_last_cycle = 0, t_critical;
// EtherCAT
ec_master_t *master = NULL;
ec_domain_t *domain1 = NULL;
// data fields
void *r_ana_out;
// channels
uint32_t k_pos;
ec_pdo_reg_t domain1_pdos[] = {
{"2", Beckhoff_EL4132_Output1, &r_ana_out},
{}
};
/*****************************************************************************/
void run(long data)
{
while (1) {
t_last_cycle = get_cycles();
rt_sem_wait(&master_sem);
ecrt_master_receive(master);
ecrt_domain_process(domain1);
rt_sem_signal(&master_sem);
// process data
//k_pos = EC_READ_U32(r_ssi_input);
rt_sem_wait(&master_sem);
ecrt_domain_queue(domain1);
ecrt_master_run(master);
ecrt_master_send(master);
rt_sem_signal(&master_sem);
rt_task_wait_period();
}
}
/*****************************************************************************/
int request_lock(void *data)
{
// too close to the next real time cycle: deny access...
if (get_cycles() - t_last_cycle > t_critical) return -1;
// allow access
rt_sem_wait(&master_sem);
return 0;
}
/*****************************************************************************/
void release_lock(void *data)
{
rt_sem_signal(&master_sem);
}
/*****************************************************************************/
int __init init_mod(void)
{
RTIME tick_period, requested_ticks, now;
printk(KERN_INFO "=== Starting EtherCAT RTAI sample module... ===\n");
rt_sem_init(&master_sem, 1);
t_critical = cpu_khz * 1000 / FREQUENCY - cpu_khz * INHIBIT_TIME / 1000;
if (!(master = ecrt_request_master(0))) {
printk(KERN_ERR "Requesting master 0 failed!\n");
goto out_return;
}
ecrt_master_callbacks(master, request_lock, release_lock, NULL);
printk(KERN_INFO "Creating domain...\n");
if (!(domain1 = ecrt_master_create_domain(master))) {
printk(KERN_ERR "Domain creation failed!\n");
goto out_release_master;
}
printk(KERN_INFO "Registering PDOs...\n");
if (ecrt_domain_register_pdo_list(domain1, domain1_pdos)) {
printk(KERN_ERR "PDO registration failed!\n");
goto out_release_master;
}
printk(KERN_INFO "Activating master...\n");
if (ecrt_master_activate(master)) {
printk(KERN_ERR "Failed to activate master!\n");
goto out_release_master;
}
printk("Starting cyclic sample thread...\n");
requested_ticks = nano2count(TIMERTICKS);
tick_period = start_rt_timer(requested_ticks);
printk(KERN_INFO "RT timer started with %i/%i ticks.\n",
(int) tick_period, (int) requested_ticks);
if (rt_task_init(&task, run, 0, 2000, 0, 1, NULL)) {
printk(KERN_ERR "Failed to init RTAI task!\n");
goto out_stop_timer;
}
now = rt_get_time();
if (rt_task_make_periodic(&task, now + tick_period, tick_period)) {
printk(KERN_ERR "Failed to run RTAI task!\n");
goto out_stop_task;
}
printk(KERN_INFO "=== EtherCAT RTAI sample module started. ===\n");
return 0;
out_stop_task:
rt_task_delete(&task);
out_stop_timer:
stop_rt_timer();
out_release_master:
ecrt_release_master(master);
out_return:
rt_sem_delete(&master_sem);
return -1;
}
/*****************************************************************************/
void __exit cleanup_mod(void)
{
printk(KERN_INFO "=== Stopping EtherCAT RTAI sample module... ===\n");
rt_task_delete(&task);
stop_rt_timer();
ecrt_release_master(master);
rt_sem_delete(&master_sem);
printk(KERN_INFO "=== EtherCAT RTAI sample module stopped. ===\n");
}
/*****************************************************************************/
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Florian Pose <fp@igh-essen.com>");
MODULE_DESCRIPTION("EtherCAT RTAI sample module");
module_init(init_mod);
module_exit(cleanup_mod);
/*****************************************************************************/