Dragon Board mezzanine sensor Adapter


#1

Hi!

I just bought the dragon board mezzanine sensor kit (http://www.96boards.org/products/mezzanine/grove-starter-kit/). I followed the guide listed here: http://linaro.co/sensorkitpdf

But I seem to feel the the low speed connector on the mezzanine sensor shield and on the base board are the same electronically since the primary reason I chose to buy this board was because I needed to easily access the uart pins, tx,rx as I was attaching an external GPS to the dragon board.

So would anyone be able to tell me about the different between the low speed 40 pin expansion connector on the mezzanine shield and the one on the dragon board base itself?

Thanks
G


#2

I received mine too. Looking at the schematics https://github.com/96boards/96boards-sensors/raw/master/Sensors.pdf

The signal coming from the DragonBoard are level shifted to different level by the TXB0108 and TXS0108 (U4, U5) or BSS138 (Q2, Q3, Q4 , Q5).
So we can use them to interface most of electronic sensors which usually use 5 or 3.3 VDC.
You have to use the level shifted signal in the Mezzanine connectors. (G1, G2, G3, etc…)

For the UART, I think you will still need an adaptor like FTDI or else but you can link it directly to the Connector P2.

The signal 96Boards LS Connector from the DragonBoard and the Mezzanine does not change.

Hope my comment will help.
Jean-Marc


#3

Followup:
Looking deeper at the schematics I noticed that UART0 is used to deal with the AVR (Arduino programming) and the UART1 is connected to the mezzanine microUSB.
So sorry, forget my comment regarding the FTDI, and try to use the UART1 on MicroUSB.

Jean-Marc