8 Channel 1-Wire Master for the B+

[repton]

I've just built up the first of the PCBs for my 8 Channel 1-Wire Master for the B+. It's electrically identical to my existing RPI3 board with physical changes to fit the B+ format. Please forgive the 26way GPIO connector as I don't have any 40way ones yet.

Paul

[dan3008]

thats handy, I've never considered using RJ45 and cat5/5e/6 cables for sensors and the like

keep up the good work

[AndrewS]

I have no interest in 1-Wire myself, but I was curious to see a USB socket mounted to the board!

So I had a look at your website and I see you're using this purely as an 'external power input' socket. However in that case, why are you using a USB A socket (which is used by host devices, i.e. the ones normally supplying the power) rather than a USB B socket (which is used by slave devices, i.e. the ones normally consuming the power)

[repton]

However in that case, why are you using a USB A socket (which is used by host devices, i.e. the ones normally supplying the power) rather than a USB B socket (which is used by slave devices, i.e. the ones normally consuming the power)

No reason really other than I guess that I happened to have some USB-A sockets kicking around when I made the first prototype of the original RPI3 a couple of years ago and it stuck. I've had a couple of people as why I don't use a Micro-USB like the RasPi itself too and my answer to that is that I worry that they're not mechanically strong enough and given I'm not short of PCB space I have decided to stick with the bigger socket. That said I do realise that with a couple of million RasPis out there using Micro-USB for power that I'm probably worrying for no reason.

Paul

[fruit-uk]

I have lots of USB A leads accumulated over the years but only a few micro USB so I'm quite happy with the choice of socket on my RPI3. The plugs are a lot easier to solder too!

[AndrewS]

However in that case, why are you using a USB A socket (which is used by host devices, i.e. the ones normally supplying the power) rather than a USB B socket (which is used by slave devices, i.e. the ones normally consuming the power)

No reason really other than I guess that I happened to have some USB-A sockets kicking around when I made the first prototype of the original RPI3 a couple of years ago and it stuck.

Heh, I wondered if it might be something like that

I have lots of USB A leads accumulated over the years

But how many of those are USB-A -> USB-A, which is presumably what this board needs? (and of course are totally against the USB spec, since you should never connect a host device directly to another host device)

The plugs are a lot easier to solder too!

Well, that's what full-size USB-B sockets are for
http://en.wikipedia.org/wiki/Usb#Connector_types

But the RPI3 board has obviously developed it's own "standard" and if all the users are happy there's no point changing it now
Apologies for the "intrusion".

[repton]

Apologies for the "intrusion".

No apology needed, I'm always up for constructive suggestions

Paul

[repton]

I've now got some 2x20 headers in stock and a batch of the PCBs made and these are now on sale:

http://www.sheepwalkelectronics.co.uk/p ... ucts_id=67

As you can see from the below photos they fit perfectly on both the A+ and B+.

RPI3v2-Amed.jpg (47.79 KiB) Viewed 3417 times

RPI3v2-Bmed.jpg (44.77 KiB) Viewed 3417 times

Paul

[stevegarratt]

Hi Paul,

I'm looking to use your products in a store monitoring application but some of the devices I want to use are i2c. Is it possible to run i2c together with the 1-wire by modifying the boards a little perhaps.

I've submitted a contact request on the Sheepwalk site but not had a reply yet.

Steve

[james-at-lo-tech]

IIRC some IBM laptops use USB-A for power input (coloured yellow I think).

[DougieLawson]

IIRC some IBM laptops use USB-A for power input (coloured yellow I think).

No they don't.

The Lenovo laptops (IBM sold out laptops to Lenovo many years ago) normally run on a 19V barrel plug. The yellow socket is an always on USB so you can charge your phone

[james-at-lo-tech]

My mistake - the plug just looks similar at a glance (see here).