Canada
Asked — Edited
Resolved Resolved by bookmaker32!

V4 Always Disconnects When Adding A Dc-Ss503v100 Compass

The V4 always disconnects when adding the compass, adding the compass via the ARC or by accessing with a i2CWrite or i2Cread from a script. Same on all three i2C ports.

Am connected to the 3.3v on the ss503 , have 20k pull ups on scl and sca and the wire length is @ 2cm.

The only way to re-establish the connection is to cycle the power on the V4.

Debug seems to indicate a timeout of some sort, but don't think the V4 should disconnected because of an i2c error .

Any suggestions or fixes , DJ, any ideas,

Thanks....

debug as follows,

Monday 29 September 2014 2:46 PM - Connected Monday 29 September 2014 2:46 PM - Setting battery monitor voltage: 6.6 Monday 29 September 2014 2:46 PM - Setting battery protection: True Monday 29 September 2014 2:46 PM - Setting i2c rate: 100000 Monday 29 September 2014 2:47 PM - Comm Err: System.IO.IOException: Unable to read data from the transport connection: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags) at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) --- End of inner exception stack trace --- at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.IO.Stream.ReadByte() at EZ_B.EZB.(Int32 , Byte[] ) Monday 29 September 2014 2:47 PM - BbytesToExpect: 8 Monday 29 September 2014 2:47 PM - ? Received: Monday 29 September 2014 2:47 PM - Disconnected


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United Kingdom
#1  

As mentioned by DJ the other day...

Quote:

The ARM chip being used on the ezb is not as friendly toward i2c devices as the microchip PIC was. With the ARM, if the i2c is not responsive it will lock up. Silly I know, but that's how it was physically designed by STM Electronics.

So, the EZ-B V4 will lock up when it encounters an I2C error, I presume this is why it's locking up. Check your wiring etc. (I2C and these compass modules are very temperamental at the best of times too)

PRO
Canada
#2  

Hi @Andre,

I just had the SS503 compass working on my desk.

Just as rich mentioned the EZ-B I2C circuitry will lock up if I2C communication isn't established and the Red LED by the reset button on the EZ-B will stay on until you reset power.

For my setup I had 3cm long wires, and no pullups (as the SS503 has 4.7kohm pullups on board already) and I used the right most I2C port which has traces closest to the ARM chip.

You can try using the 3 different I2C ports on the EZ-B to selectively tune the capacitance on the SDA and SCL lines and see which port might work better for you.

Hope that helps!

#3  

I haven't had time to try it yet but I was going to go with UART rather than i2X thinking it may be more stable. The manual says it can do either. Actually I am stalling hoping DJ would come through with the compass accelerometer he said was on the list. UART Compass

Canada
#4  

Chucked the i2c idea, going to the iPhone sensor streamer instead.