Iperf3 testing LTE speed - maximize

i've been asked to run LTE on iperf3, the result is quite bad with low kpi, do you know how to maximize the speed, until reach enough kpi?

Can you give details about your configuration ? Is it an LTE dongle you're testing with ?

Try NTTTCP-for-Linux, or netperf?
ntttcp-for-linux: https://github.com/Microsoft/ntttcp-for-linux
netperf: http://www.netperf.org/netperf/

Related

How to get a UART communication at 12 Mbps in linux (Raspbian)?

I am currently working on a Raspberry pi (Jessie Stretch), the issue is that I want to connect two FTDI FT2232H serially at 12 Mbps, but because 12Mbps is not a standard speed Raspbian does not allow me to add that baud rate. I would like to know if someone has transmitted at that speed or if someone knows how to achieve the Bit rate of 12 Mbps with the maximum baud rate in Raspbian (4,000,000) .
PS: I changed the UART clock to 64,000,000, modified the "termbits.h" library and created termios structures, but nothing worked.
Thanks.
The data sheet for the FT2232H does advertise it supports 12 Mbaud (not 12Mbps). But it looks like it comes in different modules with support for RS232, RS422, and RS485. The most typical being RS232.
I've never heard of anyone operating a RS232 connection at 120000000 baud. The typical maximum that almost everything supports is 115200. The highest I've seen is 921600. Typical RS232 cables started running into interference issues at the higher baud rates.
I suspect the 12Mbaud spec is for RS422/RS485 operation which requires different cabling and is designed for higher speeds.
If you're using an FT2232H with RS232, the speeds you're looking for are likely unrealistic. If you're using it with RS422/RS485 you can probably get there, but it will be a much more specialized endeavor. It does look like Linux does support RS485. But there's not nearly as much documentation out there as for RS232.
Can you provide any more information about the USB adapters you're using?

Linux/Qt auto detect baud rate?

I'm in a situation where we are hooking up to a device that may speak a variety of different baud rates depending on model. Some of which may be non-standard, like 10000, but that's another problem for another day.
Ideally I could use Qt to auto detect the baud rate, but from my research that's likely not possible for a few reasons, which I'm okay with. However, is there any native Linux based method to auto detect the baud rate of the connected device? Even a 3rd party open source application could suffice.
Linux serial drivers don't support autobauding, because most hardware doesn't support it, because there's no agreement on how it might work. It's highly application-specific.
If you're using FTDI serial adapters, then most of them support the bit-bang mode, and you should use them as a digital oscilloscope in such a mode to get a bitstream that's very easy to autobaud on.
On other devices, the simplest way towards autobauding is to set the device to 2-3x the highest baudrate you expect, then treat the input data like a chunked digital oscilloscope, taking account of error bits, and use heuristics to detect the baud rate. It will succeed in a surprising number of cases, but you must get the statistical model of the data source right. I don't know of any pre-canned solutions for that.
Some additional kernel support could be had to better timestamp the input from the UART (whether hardware or USB) and thus decrease the uncertainity in your data and thus the number of samples you need to take to detect baud.
Some of which may be non-standard, like 10000, but that's another problem for another day.
No biggie. I figured it out 16 years ago :) This is the answer you're looking for. If you think that the API is sick as in very, very sick, then you'd be right.

Impinj Speedway reader does not enable antenna

I am testing a Speedway reader 420 with a guard minirail antenna connected to Port 1.
The problem is that I cannot get this to work. When I telnet to the Speedway reader, and issue the "show rfid stat" command, I get this status:
> show rfid stat
Status='0,Success'
LastStatisticReset='4024'
ReaderOperationalStatus='enabled'
ReaderAdministrativeStatus='enabled'
Antenna1AdministrativeStatus='enabled'
Antenna2AdministrativeStatus='enabled'
Antenna3AdministrativeStatus='enabled'
Antenna4AdministrativeStatus='enabled'
Antenna1OperationalStatus='disabled'
Antenna2OperationalStatus='disabled'
Antenna3OperationalStatus='disabled'
Antenna4OperationalStatus='disabled'
I think this is the problem. Antenna1OperationalStatus appears disabled.
Any help about this, please?
Thanks
Jaime
I happend to me yesterday.
In my case was the physical antenna connection.
Try monitoring the antenna status while you sloooowly plug the antenna. In my case I got it connected with 4 turns, no less, no more. After realizing that it was the plug, I just needed to replace it.
I hope it helps. I took me 0.5 day of work to figure it out.

USB-Serial communication giving strange output

I'm trying to get data from a mercury analyzer (Seefelder-Messtechnik Hg Analyzer 3000) that gives output to a 9-pin R232 serial port to my OSX 10.10 laptop.
I've followed the steps described here to install the PL-2303 driver:
http://pbxbook.com/other/mac-tty.html
The device manual (http://www.seefelder-messtechnik.com/V71-3-02-21e.pdf) lists the communication protocol as "9600 Baud, 8 data bit, 1 stop bit, no log,
no parities".
I attempt to read from the device by using the 'screen' command:
screen /dev/tty.usbserial 9600
The result is a string of seemingly non-sensical characters that print to the screen in a regular interval:
�8b4����b��8b48bs��8G�8b�8���8������8����< 8�8��b��KW��\b����8b����b� �b�b����KW�K �8b��\G�� �<���8�8b�"��΁�[؁��؉���bG�3�ˁ�G��\K��[W�pb�8��΁8ʱ�\pa���ʁ�c t��8�h¡�38b�8�q�؁����\�8���bS�8b8�8�q���X��8��<��£8���2�8�����ؖ�ؖ�ؖ�8bS��\�܉�ؖ����[S�8��s���fq�8�����������8fq����������S�܊��b���b�؉����\���S��K���ݎ����S��b��b��S����S�\������KS��S�؊��\S�1S�\b�S�؉�\�ذ����KS�\����S����bS�؉�����1S�؊��[؂����ز������؉\�؂��ز��\����i���$\�$���\��8���$��\�\����܂�زXk�B��7��\k�\X�<��8Xkz��Yj��L�������H�\���]j�،k:��Yj�؈��
I've also tried using 'minicom' rather than screen, and get a different ("?]???ܰ??Yk??2"), but also non-sensical result. I saw that there was another SO query similar to mine that remains unsolved: weird characters displayed during serial communication OSX
Any tips? It looks to me that I'm not interpreting the output correctly, but I don't know what to try next.
The solution was to read from the machine at a higher baud rate (~57600), despite what the manual and online reference said. Reading at 57600 baud made the result plain-text and usable. Thanks for your ideas!
I've followed the steps described here to install the PL-2303 driver
I've also had occasional electrical ground problems with Prolific USB-RS232 adapters. Problem would manifest as garbled data that looked similar to a baud rate issue or what you posted.
You can check if it's a ground issue by measuring for continuity between the ground pin (pin #5) on the DE-9 (aka DB-9) side of the Prolific adapter and the ground pin of the USB side (pin #4, "far left", of the A connector). You'll probably measure infinite resistance with a multimeter. Try the same with a FTDI USB-RS232 adapter, and instead I get a dead short between the ground pins as expected.
Be sure to plug the instrument's and PC's power supplies into the same power strip.
As a last resort try grounding the instrument's chassis/case with the PC using copper wire

how to get the cpu's currentClockSpeed, minClockSpeed, maxClockSped

Can i get the cpu's currentClockSpeed, minClockSpeed, maxClockSped.
I have use wmi to do this,but i think the result is not good.
There are no minClockSpeed,and the currentClockSpeed and maxClockSped have the same value,
The currentClockSpeed never changed.My pc's cpu is I5-2300.it support the turbo boost.
Any help will be appreciated.
Up,i can not get the minClockSpped value.
the currentClockSpeed and the maxclockSpeed have the same value in destop pc.

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