Difference between revisions of "Xenomai:Blinking LEDs"

From ArmadeusWiki
Jump to: navigation, search
(Makefile)
Line 92: Line 92:
 
  XENO=$(ARMADEUS_ROOTFS_DIR)/usr/xenomai
 
  XENO=$(ARMADEUS_ROOTFS_DIR)/usr/xenomai
  
  CC= arm-linux-gcc
+
  CC:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-gcc
  LD= arm-linux-ld
+
  LD:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-ld
  CXX= arm-linux-g++
+
  CXX:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-g++
  AS= arm-linux-as
+
  AS:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-as
  NM= arm-linux-nm
+
  NM:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-nm
  AR= arm-linux-ar
+
  AR:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-ar
  SIZE= arm-linux-size
+
  SIZE:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-size
  OBJCOPY= arm-linux-objcopy
+
  OBJCOPY:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-objcopy
  
 
  EXEC=blink_led_xeno_userspace
 
  EXEC=blink_led_xeno_userspace
Line 105: Line 105:
 
  SRC= $(wildcard *.c)
 
  SRC= $(wildcard *.c)
 
  OBJ= $(SRC:.c=.o)
 
  OBJ= $(SRC:.c=.o)
EXEC= $(APPLICATIONS)
 
 
  CFLAGS=-g -W -Wall -I$(XENO)/include -I$(XENO)/include/native  -I$(XENO)/include/rtdm -D_GNU_SOURCE -D_REENTRANT
 
  CFLAGS=-g -W -Wall -I$(XENO)/include -I$(XENO)/include/native  -I$(XENO)/include/rtdm -D_GNU_SOURCE -D_REENTRANT
  LDFLAGS=-L$(XENO)/lib -Xlinker -rpath $(XENO)/lib -Xlinker $(XENO)/lib/libnative.a $(XENO)/lib/librtdm.a -     lpthread -lnative -lrtdm
+
  LDFLAGS=-L$(XENO)/lib -Xlinker -rpath $(XENO)/lib -Xlinker $(XENO)/lib/libnative.a $(XENO)/lib/librtdm.a -lpthread -lnative -lrtdm
 
  $(EXEC) : $(OBJ)
 
  $(EXEC) : $(OBJ)
 
$(CC) -o $@ $^ $(LDFLAGS)
 
$(CC) -o $@ $^ $(LDFLAGS)
Line 115: Line 114:
 
  .PHONY: all
 
  .PHONY: all
 
  all: $(EXEC)
 
  all: $(EXEC)
 +
 
  .PHONY: clean  
 
  .PHONY: clean  
 
  clean:
 
  clean:
Line 120: Line 120:
 
rm -rf $(EXEC)
 
rm -rf $(EXEC)
 
rm -f *.c~ *.h~ Makefile~
 
rm -f *.c~ *.h~ Makefile~
 +
 
  .PHONY: install
 
  .PHONY: install
 
  install: $(EXEC)
 
  install: $(EXEC)

Revision as of 10:36, 15 February 2010

This tutorial explains how to create a simple Xenomai application. This application will blink the APF9328DevFull user LED (connected to pin 31 of i.MXL portD; on the APF27 you would use pin 14 of portF).

Application code

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <signal.h>
#include <sys/mman.h>

#include <native/task.h>
#include <native/timer.h>

#define TIMESLEEP 1000000000
#define LED "/dev/gpio/PD31"

RT_TASK blink_task;
int fd;

void blink(void *arg)
{
    int iomask = 0x00;
  
    rt_task_set_periodic(NULL, TM_NOW, TIMESLEEP);
  
    while(1) {
        rt_task_wait_period(NULL);
        write(fd,&iomask,sizeof(iomask));
        iomask ^= 1;
    }
}

void catch_signal() {}

int main(int argc, char **argv)
{  
    signal(SIGTERM, catch_signal);
    signal(SIGINT, catch_signal);
  
    /* Avoids memory swapping for this program */
    mlockall(MCL_CURRENT|MCL_FUTURE);

    /* led device opening */
    if ((fd = open(LED, O_WRONLY)) < 0) {
        printf("Open error on %s\n",LED);
        exit(0);
    }
    /* Task Creation */
    rt_task_create(&blink_task, "blinkLed", 0, 99, 0);  
    rt_task_start(&blink_task, &blink, NULL);
    getchar();
    rt_task_delete(&blink_task);
    close(fd);

    return 0;
}

This source looks very like a classical Linux application with threads and nanosleep() function.
The only differences are on the task creation using Xenomai API:

  • Create a new task with stksize stack size, prio level of priority and mode type of creation:
 int rt_task_create(RT_TASK * task, const char * name, int stksize, int prio, int mode)
  • Launch the new task with entry function and cookie parameters:
 int rt_task_start (RT_TASK *task, void(*entry)(void *cookie), void *cookie)
  • set for the task periodic, idate time for the first release (time in nanoseconds)
 int rt_task_set_periodic (RT_TASK *task, RTIME idate, RTIME period)
  • To block the task during the previously set period:
 int rt_task_wait_period (unsigned long *overruns_r)

Makefile

The second step is to create a Makefile with specific Xenomai includes.

 ###### CONFIGURATION ######
 DEST_DIR=/tftpboot/local/bin
 ARMADEUS_BASE_DIR=../
 include $(ARMADEUS_BASE_DIR)/Makefile.in

 XENO=$(ARMADEUS_ROOTFS_DIR)/usr/xenomai

 CC:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-gcc
 LD:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-ld
 CXX:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-g++
 AS:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-as
 NM:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-nm
 AR:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-ar
 SIZE:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-size
 OBJCOPY:=$(ARMADEUS_TOOLCHAIN_PATH)/arm-linux-objcopy

 EXEC=blink_led_xeno_userspace

 SRC= $(wildcard *.c)
 OBJ= $(SRC:.c=.o)
 CFLAGS=-g -W -Wall -I$(XENO)/include -I$(XENO)/include/native  -I$(XENO)/include/rtdm -D_GNU_SOURCE -D_REENTRANT
 LDFLAGS=-L$(XENO)/lib -Xlinker -rpath $(XENO)/lib -Xlinker $(XENO)/lib/libnative.a $(XENO)/lib/librtdm.a -lpthread -lnative -lrtdm
 $(EXEC) : $(OBJ)
	$(CC) -o $@ $^ $(LDFLAGS)
 $(OBJ): $(SRC)
	$(CC) $(CFLAGS) -o $@ -c $<

 .PHONY: all
 all: $(EXEC)

 .PHONY: clean 
 clean:
	rm -rf $(OBJ)
	rm -rf $(EXEC)
	rm -f *.c~ *.h~ Makefile~

 .PHONY: install
 install: $(EXEC)
        mkdir $(DEST_DIR)/$(EXEC)
        echo "$(EXEC):native:!./$(EXEC);popall:control_c" > /$(DEST_DIR)/$(EXEC)/.runinfo
	cp $(EXEC) $(DEST_DIR)/$(EXEC)

 .PHONY: mrproper
 mrproper: clean
	rm -rf $(DEST_DIR)/$(EXEC)

ARMADEUS_BASE_DIR needs to be adapted to the correct path where the Armadeus buildroot is installed.
DEST_DIR assumes you used an NFS mount on /tftpboot/local as /usr/local on the board.

Compilation, installation and run

 $ make

If you setup the NFS as indicated above, you can install the application on your board with :

 $ make install

Otherwise you can manually copy blink_led_xeno_userspace exe to your board (/usr/local/bin/).

Running

On your APF, you must change directory to /usr/local/bin and type :

 # xeno-load blink_led_xeno_userspace

Links