How do I capture all the packets in radio range of a particular node in contiki?
While reading the contiki mailing lists and contiki github, I could read people saying something about making changes to core/dev/cc2420.c file. Some people spoke about setting or resetting values of CC2420_CONF_AUTOACK.
I nowhere found proper information regarding putting a node in promiscous mode. Please help.
I guess what you mean to do is to disable the hardware address filtering. There is a radio API for this in Contiki:
#include "dev/radio.h"
// ...
radio_value_t radio_rx_mode;
if(NETSTACK_RADIO.get_value(RADIO_PARAM_RX_MODE, &radio_rx_mode) == RADIO_RESULT_OK) {
radio_rx_mode &= ~RADIO_RX_MODE_ADDRESS_FILTER;
NETSTACK_RADIO.set_value(RADIO_PARAM_RX_MODE, radio_rx_mode);
}
You can also disable automatic acknowledgements by removing the RADIO_RX_MODE_AUTOACK bit of the rx_mode, but that's a different setting.
Related
I want to know if some API/code exists to disable a specific item in the (current) network connection properties?
If yes, could you show a working code example, explain the details, and point out some limitations (if they exist) of the technique used?
The API to disable these bindings is INetCfgBindingPath::Enable. The bindview sample illustrates how to call the API.
From Windows 8 and later, you may alternatively invoke the WMI method /root/standardcimv2/MSFT_NetAdapterBindingSettingData::Disable. Here's a line of PowerShell that illustrates how to disable the bindings from a NIC named "mb-port" to the "ms_msclient" driver (aka wkssvc):
Get-CimInstance -Namespace root/standardcimv2 -Query 'SELECT * FROM MSFT_NetAdapterBindingSettingData WHERE Name = "mb-port" AND ComponentID = "ms_msclient"' | Invoke-CimMethod -MethodName Disable
Note that the GUI is being sneaky: it merges multiple bindpaths into the same checkbox. In the example you have highlighted, there are likely 2 bindpaths from ms_msclient to the NIC: one over IPv4 and one over IPv6. The GUI disables/enables all paths when you clear/tick the checkbox. If you come in through the API and want to do the same, you'll need to enumerate all bindpaths that start from ms_msclient and go to the NIC mb-port.
I installed ROS melodic version in Ubuntu 18.04.
I'm running a rosbag in the background to mock cameras in messages rostopics.
I set the camera names in rosparams and iterated through it to capture each camera topics.
I'm using message_filter ApproximateTimeSynchronizer to get time synchronized data as mentioned in the official documentation,
http://wiki.ros.org/message_filters
But most of the time the callback function to ApproximateTimeSynchronizer is not being called/is having delay. The code snippet I'm using is given below:
What am I doing wrong here?
def camera_callback(*args):
pass # Other logic comes here
rospy.init_node('my_listener', anonymous=True)
camera_object_data = []
for camera_name in rospy.get_param('/my/cameras'):
camera_object_data.append(message_filters.Subscriber(
'/{}/hd/camera_info'.format(camera_name), CameraInfo))
camera_object_data.append(message_filters.Subscriber(
'/{}/hd/image_color_rect'.format(camera_name), Image))
camera_object_data.append(message_filters.Subscriber(
'/{}/qhd/image_depth_rect'.format(camera_name), Image))
camera_object_data.append(message_filters.Subscriber(
'/{}/qhd/points'.format(camera_name), PointCloud2)
topic_list = [filter_obj for filter_obj in camera_object_data]
ts = message_filters.ApproximateTimeSynchronizer(topic_list, 10, 1, allow_headerless=True)
ts.registerCallback(camera_callback)
rospy.spin()
Looking at your code, it seems correct. There is, however, a trouble with perhaps bad timestamps and ergo this synchronizer as well, see http://wiki.ros.org/message_filters/ApproximateTime for algorithm assumptions.
My recommendation is to write a corresponding node that publishes empty versions of these four msgs all at the same time. If it's still not working in this perfect scenario, there is an issue with the code above. If it is working just fine, then you need to pay attention to the headers.
Given that you have it as a bag file, you can step through the msgs on the command line and observe the timestamps as well. (Can also step within python).
$ rosbag play --pause recorded1.bag # step through msgs by pressing 's'
On time-noisy msgs with small payloads, I've just written a node to listen to all these msgs, and republish them all with the latest time found on any of them (for sync'd logging to csv). Not optimal, but it should reveal where the issue lies.
During my test on Pepper, I found some difficulties in realizing continuative collaborative dialog.
In particular, after about 10 minutes, it seems that the ALSpeechRecognition engine stops working.
In other words, Pepper dialog panel remains empty and/or the robot does not understand my words, even if the structure worked some minute before.
I tried to stop and restart it (i.e., the engine) via SSH terminal, by using:
qicli call ALSpeechRecognition.pause 1
qicli call ALSpeechRecognition.pause 0
It should restart the engine according to the guidelines shown here, but it does not work.
Thank you so much guys.
Sincerely,
Giovanni
According to the tutorial, starting and stopping the speech recognition engine is done by subscribing/unsubscribing it.
The recommended way to do this is unsubscribing and subscribing back to it. For me it also worked changing the speech reco language and chaging it back to the one you had previously.
Luis is right and to do so just create a function as below given and call it if ActiveListenning event comes false from ALSpeechRecognition module. Note: Use ALMemory module to get data from ALSpeechRecogntion.
asr_service = ALProxy("ALSpeechRecognition",ip,port)
memory = ALProxy("ALMemory",ip,port)
def reset():
asr_service.unsubscribe("ASR_Engine")
asr_service.subscribe("ASR_Engine")
ALS = memory.getData("ALSpeechRecognition/ActiveListening")
if ALS==False:
reset()
I would like to know which library should I use to manipulate mote leds.
I tried to use Led Contiki Module but I don't know which header file include.
Is there someone who can help me ?
Look in the platform-conf.h in eg contiki/platform/sky/. There you'll find the definitions you can use, of eg LEDS_RED.
Then, in your application,
#include "leds.h"
...
leds_on(LEDS_RED);
leds_off(LEDS_GREEN);
leds_toggle(LEDS_RED);
leds_off(LEDS_ALL);
You can look in leds-arch.h to see how the implementations sets/get LED state.
e.g. at contiki-2.7/core/dev you can find leds.c and leds.h.
In leds.c are implemented functions for accessing LEDs, e.g. leds_on(...), leds_off(...).
In leds.h are inter alia specified names of LEDs and their number values, e.g. #define LEDS_GREEN 1
To your question: #include "dev/leds.h"
I'm trying to implement a simple connection saturation algorithm for a bunch of nodes running hostapd. On having max_num_sta connections, I want hostapd to move into hidden SSID mode (ignore_broadcast_ssid=0). I have updated src/ap/beacon.c to include a simple conditional statement and recompiled successfully, but my SSID still keeps showing up when the node is "saturated":
if ( hapd->num_sta >= hapd->conf->max_num_sta){
hapd->conf->ignore_broadcast_ssid = 1;
}else{
hapd->conf->ignore_broadcast_ssid = 0;
}
Am I missing something?
You need to reload the configuration of the bss once you've edited it.
Try invoking hostapd_reload_bss (in src/ap/hostapd.c) for each defined bss. Note that if you choose to invoke hostapd_reload_config, all currently connected stations shall be deauthenticated, so don't do that.