WiFi connection is not working

[DVE]

Hi all,

I bought Red Pitaya board today, was going to start it... And the problem is, I don't have ethernet connection, only WiFi.
It's a bit disappointing that there is no manual on the redpitaya.com, in the wiki I also find nothing (maybe it is somewhere, but it's good hidden).
The STORE button is much more visible btw

I connected remotely to RP via USB cable.
So, the question is: what files I need to create to establish WiFi connection to my router?
Now I have this:

1) lsusb
Bus 001 Device 002: ID 148f:5370 Ralink Technology, Corp. RT5370 Wireless Adapter
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Looks like, adapter is working.

I created files:
2) sudo nano /etc/network/inferface
auto wlan0
iface wlan0 inet dhcp
pre-up wpa_supplicant -B -D wext -i wlan0 -c /etc/network/wpa_supplicant.conf
post-down killall -q wpa_supplicant
udhcpc_opts -t7 -T3
Is this file and path ok? Lots of parameters, I don't understand (t7, T3, etc).

3) sudo nano /etc/network/wpa_supplicant.conf
network={
ssid="my SSID_here"
scan_ssid=1
proto=WPA2 RSN
key_mgmt=WPA-PSK
pairwise=CCMP TKIP
group=CCMP TKIP
psk="my pass here"
}
Is this file and path ok?

So, the final result after sudo reboot: nothing.

iwconfig gets this:
wlan0 IEEE 802.11bgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=20 dBm
Retry short limit:7 RTS thr:off Fragment thr:off

ip addr show:
wlan0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
link/ether 00:13:ef:c0:1f:58 brd ff:ff:ff:ff:ff:ff
Why "DOWN", btw?

ifup wlan0:
ifup: command not found

What I'm doing wrong?
Thanks.

PS: Addition - I tried to add "/etc/wpa_supplicant/wpa_supplicant.conf", and getting the error: "Error writing /etc/wpa_supplicant/wpa_supplicant.conf: Read-only file system".
Which file path is correct?

Addition-2: I tried this manual http://www.rs-online.com/designspark/as ... 20v1.0.pdf
There is no /etc folder at SD card root. File system was changed in newer versions?

[pavel]

Hi,

What SD card image are you using?

Right now, the SD card images available from http://redpitaya.com/quick-start have a compatibility problem. Hopefully, they'll be soon fixed by the Red Pitaya developers. Because of this problem, I had to temporary remove all my applications from the Red Pitaya application marketplace.

As a workaround, I’d suggest to use the Debian based SD card images from the following links:
http://pavel-demin.github.io/red-pitaya ... -ecosystem
http://downloads.redpitaya.com/downloads/0.95

Normally, it should be enough to replace the content of /etc/network/interfaces.d/wlan0 with the following lines:

Code: Select all

allow-hotplug wlan0
iface wlan0 inet dhcp
  wpa-ssid MYSSID
  wpa-psk MYPSKHASH
  wpa-group CCMP

Commands to restart wlan0 with the Debian based (0.95) images are:

Code: Select all

ifdown wlan0
ifup wlan0

Best regards,

Pavel

[DVE]

Thanks, man! 0.95 version works.

This is my config:
1) /etc/network/interfaces.d/wlan0
allow-hotplug wlan0

# For dynamic
#iface wlan0 inet dhcp
# For static
iface wlan0 inet static
address 192.168.2.100
netmask 255.255.255.0
gateway 192.168.2.254

wpa-conf /etc/network/wpa_supplicant.conf

2) /etc/network/wpa_supplicant.conf
network={
ssid="TP-LNK450-1"
psk="xxxxxx"
}

[DVE]

Small additional question.

1) I tried to start application from the web interface (Oscilloscope, Generator) with 0.95 and got the message like "Licence error" and "work in demo mode".
Is 0.95 is not compatible with Bazaar now? I need only 0.96 for it?

2) I want to test HDSDR receiver, but it's not comfortable to reinstall all SD-card image.
Is it possible to download only linux binaries for 0.95 and launch them?

Thanks.

[pavel]

In 0.95, the "pro" applications aren't free and require a license. In 0.96, they work without license. But 0.96 currently doesn't work with the SDR applications.

You can also try my Debian based SD card image from http://pavel-demin.github.io/red-pitaya ... -ecosystem. It's based on 0.95 and includes the oscilloscope application that works without license. This image also comes with more Linux drivers than the original 0.95 image. For example, it works with USB audio cards.

I've just put back all my SDR applications to the Red Pitaya application market place. So, you can install and run them via the on-board web interface.

I want to test HDSDR receiver

The SDR receiver project is outdated. Please use the SDR transceiver project. It also works as a receiver and can be used with HDSDR .

[DVE]

It works, and HDSDR is working with transceiver app. Thanks for the good job

[DVE]

Its a pity to say, but WiFi is almost useless for the Red Pitaya.

I have the router in the same room, so there are no problems with signal strength. And when using Spectrum Analyzer, the image refresh rate is about 2-3s, its absolutely not comfortable.
With HDSDR maximum spectrum width is 100KHz, if I set more, there are clicks and sound lags.

I have 10Mbps with a speedtest.net even with the internet connection, so WiFi speed is enough. Ping to the Red Pitaya is 1-4ms, it looks also ok. So, I don't understand why it is so slow.

[pavel]

Its a pity to say, but WiFi is almost useless for the Red Pitaya.

With HDSDR maximum spectrum width is 100KHz, if I set more, there are clicks and sound lags.
I have 10Mbps with a speedtest.net even with the internet connection, so WiFi speed is enough. Ping to the Red Pitaya is 1-4ms, it looks also ok. So, I don't understand why it is so slow.

It really depends on application and on quality of the WiFi equipment connected to Red Pitaya.

If an application requires more network bandwidth than your WiFi equipment can provide, then of course there will be problems.

If you have only 10 Mbit/s then I'd say that your WiFi equipment works in the 802.11g mode. Could you please check that your WiFi adapter and WiFi access point support 802.11n?

I have a router that supports 802.11n and the maximum transfer rates that I obtained with three different Wi-Fi adapters are between 36 Mbits/s and 48 Mbits/s. You can find more details in this post

SDR transceiver with the 100 kSPS sample rate requires network bandwidth of slightly more than 6.1 Mbit/s (100000 * 64 / 1024 / 1024). So, indeed 100 kSPS should be OK but 200 kSPS is too much for your 10 Mbit/s WiFi connection.

I've just tested SDR transceiver with TL-WN722N (Atheros AR9271 chipset, external antenna) and my 802.11n router. 500 kSPS works fine. 1250 kSPS is not usable with my WiFi connection.

[DVE]

I use chinese 802.11n usb dongle on Red Pitaya. Speedtest-cli shows 3.8/1.6 MBit UL/DL on Red Pitaya and 9/3 MBit on desktop (it's the internet speed, LAN speed of course higher - I don't know how to measure it).
I think 3.8MBit is anyway enough to show spectrum analyser data faster than 1 image per second?

There is more interesting problem with WiFi. When I use HDSDR transceiver, its slow but it's working. When I use HPSDR transceiver and PowerSDR, WiFi stop working after 1-2 minutes - no ping, no internet. PowerSDR spectrum refresh is about 1fps, so it looks like, it fills all channel bandwidth with packets, and connection became broken.

PS: About the connection speed, did a measure today:
iperf3 -c 192.168.2.100
[ 4] 0.00-1.01 sec 328 KBytes 2.68 Mbits/sec
[ 4] 1.01-2.00 sec 368 KBytes 3.03 Mbits/sec
[ 4] 2.00-3.00 sec 313 KBytes 2.56 Mbits/sec
[ 4] 3.00-4.00 sec 633 KBytes 5.19 Mbits/sec
[ 4] 4.00-5.00 sec 154 KBytes 1.27 Mbits/sec
[ 4] 5.00-6.01 sec 290 KBytes 2.36 Mbits/sec
[ 4] 6.01-7.00 sec 185 KBytes 1.52 Mbits/sec
[ 4] 7.00-8.00 sec 300 KBytes 2.46 Mbits/sec
[ 4] 8.00-9.00 sec 38.2 KBytes 313 Kbits/sec
[ 4] 9.00-10.00 sec 540 KBytes 4.43 Mbits/sec

Its not perfect, but not too bad. I think even 2MBit bandwidth should be enough to display Spectrum Analyser data, now its totally unusable - 1s data, 2s freezing, 1s data, 2s freezing.
How much data block is needed to send a spectrum line with 800px width?