Quick Summary Of Pinouts And Connections

[ianfallon]

NOTE! ARF and Baro chips are now obsolete and replaced with the new plug in board coming Spring 2016!!

Please someone double check this for me, but here's a quick summary of pin-outs and connections in one place:

ARF

With the ARF face up (chips up) with the antenna connection at the top, pin 1 is the topmost pin on the left edge. Pin 2 is below that etc. with pin 10 the bottom-most on the same (left) edge.

PIN 1      3.3v IN - connect to any 3.3v output from Slice of POD / POD or Adafruit Baro chip VOUT, or Digole board 3.3v output.
PIN 2      TX - connect to GPIO pin 10 RX
PIN 3      RX - connect to GPIO pin 8 TX
PIN 10   GND - any GND on POD or GPIO (pins 6,9,14,20,25)


ADAFRUIT BARO

Vin 5v      Connect to any 5v output from Slice of POD board or GPIO pin 2
GND         Connect to any GND from GPIO (pins 6,9,14,20,25) or Slice of POD board etc
SDA         Connect to SDA on GPIO pin 3
SCL         Connect to SCL on GPIO pin 5


HOBBYTRONICS BARO

Vin 3v      Connect to any 3.3v from Slice of POD or POD or Adafruit Baro chip or Digole board
GND         Connect to any GND from GPIO (pins 6,9,14,20,25) or Slice of POD board etc
SDA         Connect to SDA on GPIO pin 3
SCL         Connect to SCL on GPIO pin 5


Notes

- GPIO 3.3v supply (pin 1) is NOT sufficiently powerful to use, hence the use of the POD or Digole boards.
- Take extra care with the GPIO pin numbering. It is not like regular IC numbering (down once side and up the other), instead even numbers are on one side, odd on the other.

[Ian Melville]

Can this thread be made stickie?

[neilmurg]

I've read this for the 3rd time and suddenly I understand it! I've also been staring at the baro, ARF, slice of POD and Pi and cross checking while the soldering iron sits there smoking gently. Previously I'd wondered if the Slice of POD had to fit over certain pins on the Pi. Don't judge me 
Thanks!

[Gyronaut]

Hi Ian,
I've been following the forum on whether or not it’s a good idea to install a Baro device to my PAW module. It now appears prudent to install a Baro unit even though my PAW device has been successfully built and tested.
I've decided to purchase the Hobbytronics Baro (MPL3115A2).
Regarding the method of installation for the Baro unit, would you be able to advise me on the required installation process?
My main concerns are as follows:
1.   Do I need to construct a new IDC connector with modified ribbon cable that now includes the additional wires needed for soldering to the Baro unit?
2.   Do I also need to connect the Baro unit in any way to the ARF or Digole boards?
Cheers,
Paul.

[colinmackenzie]

Hi Paul,

Not sure what your setup is, ie ARF breakout boards etc.

If it's any help, what I did...

Holding off  fitting the ARF as per Lee's advice but fitted the Hobbytronics Baro as follows:

It doesn't come with any connectors, I got some of these and broke to size: http://cpc.farnell.com/multicomp/mc34743/header-1-row-vert-24way/dp/CN14499?ost=CN14499&selectedCategoryId=

You can get various sizes I opted for the 24 way. Unfortunately the minimum you can buy is a pack of 10. I do have other uses for the remainder so I didn't mind. I didn't search ebay so you could get them there I dare say.

Next I used 10cm Female to Female jumper wires to connect the Baro to the GPIO pins. I got these http://www.ebay.co.uk/itm/331134442188?_trksid=p2060353.m2749.l2649&var=540346391389&ssPageName=STRK%3AMEBIDX%3AIT

I put some insulating tape around any parts of the Baro board that were in danger of touching any metal on the RPi and just tucked into the box.

This flexibility allows me, when the time, comes to either mount it on a breakout board with an ARF or leave as is.

Hope this makes sense.

Cheers,
Colin

[ianfallon]

Hi,

I used the Slice of Pod so I just connected more wires from it to the Baro chip.

I am not sure about this but after moving the Baro to the other side of the SOP board from the ARF it worked more reliably. Whether this was heat, RF or something else I am not sure.

[Gyronaut]

Hi,
I had assembled my PAW module in accordance with Lee’s Pilot Aware Construction Manual version 0.2. So the Ciseco ARF module and Digole regulator board are built as per the manual pictures.

As I now want to amend my completed radio module and add the Hobbytronics Baro, I estimate that I should carry out following modification work:

1.   De-solder the current modified 40pin IDC/Ribbon cable from the Digole regulator board and discard the IDC/Ribbon cable.

2.   Construct a new IDC/Ribbon cable as per manual V0.2 (with wires 2,6,8 and 10) however, add the following wires that will be used for soldering to the Hobbytronics Baro board (GND, SDA and     SCL). NOTE: GPIO 3.3v supply (pin 1) is NOT sufficiently powerful to use, hence the use of the Digole board.

Here is the big question… where on the Digole board can I solder a wire that will provide 3.3v to power the Hobbytronics Baro board?

I like like the idea of using the SOP board but as I now have the Digole built I would prefer to keep using it... unless there is a strong recommendation that I change to the SOP?

Rgds, Paul.

[ianfallon]

Sounds right - I guess the same 3.3v out from the Digole that powers the ARF?

The SOPod board has 4 advantages I like:

- no need for soldering the Digole

- no need for new GPIO connector cables as more GPIO connections are needed (I guess you could not cut the others off at the connector but you end up with a lot of cable to put somewhere in the case)

- plenty of 5v and 3.3v (and GND) solder points.

- physical board to stick things to e.g the ARF and Baro

[Gyronaut]

Okay Ian you've convinced me.

I'm not proceeding any further with modifying the IDC/Ribbon cable and Digole board but instead I'm going to order the following recommended items:
•   40pcs 10cm Jumper Wire Cable;
•   Multicomp MC34743 Board-To-Board Connectors;
•   Wirelessthings B024 Slice of Pod, RPI Stacker Adaptor;

It does appear that using the above items is less fiddly and more adaptable for future enhancements?

Many thanks,

Paul.

[ianfallon]

Bear in mind the recommendation from Lee is not to pursue the internal side of the PAW just yet though as it may change.

If you want to play and don't mind the risk of change then that's the way I'd build it at the moment.