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FEZ Cobra II - RedPine Signals 9110 Wifi


#1

Hi guys,

I just received my first FEZ Cobra II (Rev B) - Wifi version, and I was experimenting with the builtin wifi module.

I am using the 2013-02-14 SDK, the G120 firmware is 4.2.9.0
RS9110 firmware version Number is 4.4.5
RS9110 driver version Number is 4.4.5

As I was about to join my network (SecMode 2) with a 34 chars password, I am getting this exception:

#### Exception System.IndexOutOfRangeException - 0xa9000000 (1) ####
#### Message: 
#### GHI.Premium.Net.RS9110Helper::JoinRequest [IP: 0000] ####
#### GHI.Premium.Net.RS9110Helper::Join [IP: 001c] ####
#### GHI.Premium.Net.WiFiRS9110::Join [IP: 008b] ####
#### GadgeteerApp1.Program::ProgramStarted [IP: 0114] ####
#### GadgeteerApp1.Program::Main [IP: 0015] ####
#### Exception GHI.Premium.Net.NetworkInterfaceExtensionException - 0x00000000 (1) ####
#### Message: 
#### GHI.Premium.Net.WiFiRS9110::Join [IP: 00e7] ####
#### GadgeteerApp1.Program::ProgramStarted [IP: 0114] ####
#### GadgeteerApp1.Program::Main [IP: 0015] ####

A first chance exception of type ‘GHI.Premium.Net.NetworkInterfaceExtensionException’ occurred in GHI.Premium.Net.dll

In a unsecured (SecMode 0) network, the Join returns without any exception.

Can this be because of the length of the password? The maximum for WPA2 is 64 chars. Is it possible for you to give it a try?
I can’t change this PSK right now, I will run some tests later with shorter PSK’s to see if this problem goes away.

Thank you very much.


#2

Can you post your code please?

By the way there is a newer hot fix firmware:

http://www.tinyclr.com/forum/topic?id=11074


#3

32 characters is the limit on the password length. I will forward this to the appropriate person to look into this further in the future.


#4

@ Architect - Thanks for the new firmware info.

The code is pretty much the same as in http://www.tinyclr.com/codeshare/entry/671 with the difference of the SSID value, password and without the T35 code.

Also changed the wifi object creation with this:

        wifi = new GHI.Premium.Net.WiFiRS9110(Microsoft.SPOT.Hardware.SPI.SPI_module.SPI2, GHI.Premium.Hardware.G120.Pin.P1_10, GHI.Premium.Hardware.G120.Pin.P2_11, GHI.Premium.Hardware.G120.Pin.P1_9, 4000);

I get the pins from the board schematics and I believe it is ok (it works anyway). Probably there is a better way of creating this class…


#5

@ Steven - That explains… Thank you.

PS: pretty fast response :slight_smile:


#6

@ Steven - Sorry to bother you guys. I think you are doing a terrific job, and I know that there are many other issues that you are working on with much higher priority, but can you give me an hint if you are going to change this password length limitation, and if so, when?

From what I’ve read from the net (http://en.wikipedia.org/wiki/Wi-Fi_Protected_Access#Security) using a simple google query (https://www.google.com/#q=wpa-psk+maximum+length) they all say that the wpa-psk key can be from 8 to 63 printable ASCII chars or 64 hex. So, why a 32 char limitation?

My problem is that no one here where I work wants to change the psk length. The other ssid’s are either with longer psk’s or with 802.1X (EAP). If only I could enter the AES 256bit directly, I could do the key derivation calculations myself.

Is there a way to enter the AES 256bit key directly?

I really don’t know what to do from now on. Can you please give me an hint of your plans about this? Thank you guys @ GHI.


#7

Unfortunately, to be honest, this is not going to change for a long time, maybe not at all. While this is simple, this requires intensive work and it maybe related to limitation on the redpine module itself, which is outside our control.

That said, we see your need and we will see what we can do to solve this, just can’t promise at this point :slight_smile:


#8

@ Gus - Hi Gus.

You are right about this being a limitation on the module itself. With your answer, I started looking for manuals for the redpine module and found a sentence in a manual that says this about the psk length: “A maximum of 63 bytes is supported in firmware version 4.5.0 and upwards. For earlier versions, a maximum of 32 bytes is supported”.

I’ll just have to convince my colleagues to create a new ssid with a 32 chars or less psk…

Thanks again for your time.