I'm trying to build CAPL code to monitor Ethernet commuincation for automotive items.
I have used [on ethernetPacket *] function to capture for some/ip messages in trace.
But there were some problem when I use this function.
I think there were missing packet which I want to capture due to Baud Rate I guess
(Bause Rate: 1000Mbps)
My code like this:
on ethernetPacket *
{
data_to_be_Captured = thys.byte(05);
data_to_be_Captured2 = thys.byte(07);
sysGetVariableString(sysvar::TAP_Var::sample,buf,elcount(buf));
sysSetVariableString(sysvar::TAP_Var::sample,Char_arr);
......
}
With this Ethernet function in CAPL, It was possible to capture some pacekt.
But one of them was missing when I debug it.
I guess this issue caused by speed of transimission of Etherent packet.
Is there any way to resolve this problem?
Thanks
BR
Related
i know this forum dislikes "open" questions like this, nevertheless i'd like somebody to help untie the knot in my head, much appreciated.
The goal is simple:
read a stereo 32bit 44100 S/s I2S signal from 2 adafruit sph0645 mics
create a wav-header and store the data onto an SD-card
I've been at this for a few days now and i know that this will be much more complicated than i originally thought. Main reason: signal quality. Like most tutorials on this subject the simplest "hello world" for these mics is a looped polling for I2S-samples. Poll, fill buffer, output via serial or write to SD-card. This returns a choppy, noisy, sped up version of RL-audio. The filling of the internal DMA-buffers can be seen as constant, but the rest is mostly chaos, so
how to i sync these DMA-buffers with the rest of my code?
From experience with the STM32 HAL i'd imagine some register which can be set to throw an interrupt whenever a buffer is full, or an event which can be sent between tasks via queues. Examples on this subject either poll in a main loop with mono an abysmal sample-rate and bit depth or use pages of overkill code and never adress what it does, "just copy and it works", not good. Does the ESP32-Arduino framework provide some way to to this properly? The espressif-documentation isn't something to look forward to, since some of their I2S interface functions don't even work (if you are researching this topic as well, you too might have noticed that i2s_read only returns zeros). Just a hint into the right direction would help, i'm writing my own code anyway. Interrupts? Events? Timers? Polling for full buffers? Only you might know.
have a good one, thx
Thanks to https://github.com/atomic14/ i now have an answer for a syncing-method which works very well. This method has been tried by https://esp32.com/viewtopic.php?t=12546 who also didn't fully understand what was going on: the espressif i2s-interface offers a flag stored in an event which is triggererd every time one of the specified dma-buffers has received a full set of data, ergo, is full. It looks like this:
while(<your condition>){
i2s_event_t evt;
if (xQueueReceive(<your queue>, &evt, portMAX_DELAY) == pdPASS){
if (evt.type == I2S_EVENT_RX_DONE){
size_t bytesRead = 0;
do{
//read data via i2s_read or i2s_read_bytes
} while (bytesRead > 0);
No data is stored in this queue, but rather a flag which can then be used to synchronize dma-filling and further buffering/calculating/sending the read data.
HOWEVER this only works if you install the i2s driver in a specific setup. Instead of using
i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
in your setup, you can activate the "affinity" for events by passing a queue-handle and a lenght:
i2s_driver_install(I2S_NUM_0, &i2s_config, 4, &<your queue>);
hope this helps getting started, it sure did help me.
I use a STM32F103C8T6 as a transmitter and an Arduino Uno as a receiver.
I cannot receive the value I am interested in. I have changed delay durations after each send and also CE pulse. I sometimes get it worked on spec by playing with delay durations.
To exemplify, I add a 200ms delay after TX function is executed and receiver receives very well then I disconnect the receiver and then when I connect it again, it receives nothing but zero.
Very similar situations occur when I play with CE pulse duration.
I cannot get it worked neither with auto-ack nor simple rx-tx operation.
I would like to mention that when I change roles (TX device is Arduino and RX device is STM) everything works perfectly.
I've checked STM32 by a logic analyzer to see whether the payload is filled properly or not and could not see any problem.
After I fill the payload, I check FIFO_STATUS register and everything is fine.
After I apply a pulse for a certain duration, I check STATUS register and can see that TX_DS bit is set.
I've discovered that just applying 10us pulse on CE may not be enough. It can take up to 500us.
Then decided to set CE pin high until TX_DS bit is set, but this method also did not work.
void TX_Mode(uint8_t data2send)
{
Flush_TX();
CleanInterrupts();
SetPRIM(PRIM_TX); //set as transmitter
csn_low(); //CSN=0
HAL_SPI_Transmit(&hspi2, &COMD_W_TX_PAYLOAD, 1,150); //send command to write to payload
HAL_SPI_TransmitReceive(&hspi2, &data2send, &dummy, 1, 150); // fill the payload
while(HAL_SPI_GetState(&hspi2) != HAL_SPI_STATE_READY);
csn_high();
ChipEnable_high();
while( !(TXDS_Bit_Is_Set() )); //wait until payload is sent
ChipEnable_low();
}
I have two xbee's series 1. I have them as endpoint devices working in API mode and talking to each other. The first xbee is attached at a raspberry pi, while the other is on my pc where I see the terminal tab of XCTU program. The baud rate I use is 125000.
From raspberry pi I try to send a jpg image which is 30Kbytes. I send data frames 100 byte long (the biggest as it is said in the xbee documentation). Inside a loop I create and send the packets, I have also a cout statement that prints the loop number. Everything is fine and all bytes are sent. When I comment out the cout statement not all bytes are sent.
From what I have understood the cout statement works as a delay between packets, but I still cannot understand why is this happening as it is supposed that I use the half speed ...
I hope I was clear and look forward for a reply.
UPDATE
Just to summarize, i changed baud rate to 250000 where there is the same behavior as in 125000. I also implemented hardware flow control by checking cts signal. When xbees are in transparent mode I need a delay between sending characters at around 150us. The same goes for api mode too. The difference with 125000 baud rate in api mode was that the delay needed, was enough to be betwween each data packet, but in 250000 the delay is needed between each byte that i send. If i do the above everything goes well.
The next thing i did was to plug both xbees in my pc in transparent mode. I went to terminal tab of xctu software where i chose assemble packet and sent at around 3000 bytes to the other xbee. The result was the same. The second xbee received at about 1500 bytes and then each time that i was sending one byte from the first to the second, the "lost bytes" were being received at packets of 1000. :/
So could anyone know what am I doing wrong?
You should connect the /CTS pin from the XBee module into the Raspberry Pi, and have your routine stop sending data when the XBee de-asserts it.
At higher baud rates, it's possible to stream data into the XBee module faster than it can send to the remote module. The local XBee module uses the /CTS pin to notify the host when its buffers are almost full and the host should stop sending. People refer to this as hardware flow control.
It may be necessary to modify the serial driver on the Raspberry Pi to make use of that signal -- it should pause the transmit buffer when de-asserted, and automatically resume sending when re-asserted.
I have set up scapy on linux (raspian on RPI) for sniffing WiFi packets using WiFi adapter (b/g) in monitor mode. I am not sure if scapy by default hops on all the channels of the b/g protocol, or sticks to just one of them.
I'd like to have the capability to sniff different channels by hopping on to them, and to have capability to configure the dwell time on each channel, all using snapy. Can some one help me how to do that? Thanks a lot.
No, Scapy won't do channel hopping for you.
I don't think Scapy has a way to control your interface's channel, but you might have a job (outside your script or fork()-ed from it) that would do something like
import os
import time
chans = [1,6,11]
wait = 1
i = 0
while True:
os.system('iw dev monitor0 set channel %d' % chans[i])
i = (i + 1) % len(chans)
time.sleep(wait)
Or something with subprocess.call() instead of os.system if you prefer.
I have an Arduino with a WiFly shield, everything works perfectly!
The thing is, when I want to turn on an LED, I open in my
webbrowser:
192.168.1.120/ledon/
(I made a program which handles this URL).
But the thing is; when I make a request, I must wait 1-2 seconds before I can do another one.
So, it is very long, and if I want to control motors, it is just too long.
So, instead of using an HTTP request, I want to use something else which can be faster.
Something "super fast".
I just need to tell the Arduino:
- go direction 1
- go direction 2...
- turn on LED
- turn off LED
- tell me the light level (which return a int)
So it is just about a small amount of data.
Can you show me a way? (Telnet, UDP, OSC?)
For your arduino, have a look at just using sockets or even encoding the data in the URL requested.
You shouldnt get less than about 0.8 Seconds Lag maximum.
How big is your program for handling the Url /ledon/ ?
Using pure packets (usually TCP) from your computer to the arduino is faster sometimes..
But you may need to code a application to handle the packets on the pc.
There is the option of Javascript to parse data back and forth e.g. reading the light level and such.