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Art
- 25th May 2013, 16:19
Hi Guys,
I want to interface an 8 bit pic to the iPhone over bluetooth using a keyboard interface,
so a pic connected to a BT keyboard chip can send text strings and press enter.
In case you didn't know, that's how the iCade joystick communicates with iPhones.

Any recommendations for a bare bluetooth keyboard chip that can be soldered by a Human?
(ie. not a BGA, and available in small quantities).

I actually want to connect an external GPS device to a pic,
then the pic to the bluetooth keyboard, which is paired with the iPhone.
Cheers, Art.

prstein
- 25th May 2013, 22:59
Hello Art,

Although I would LOVE to be proven wrong, I don't believe what you are seeking is possible using an un-jailbroken iPhone. My understanding is that Apple only allows "approved" devices to connect via Bluetooth. An extra chip, supplied by Apple, adds something or other to the Bluetooth protocol that allows communication to occur. We investigated adding iPhone support for a product last year; our conclusion was that we would have to limit it to Android and Windows phone.

Again, if I am demonstrably wrong on this it would make my day (and make customers very happy).

Best Regards,
Paul

Art
- 26th May 2013, 01:30
I connected a Sony bluetooth keyboard to my iPhone yesterday,
and before that, some other cheap knockoff bluetooth keyboard.
Works with iPad as well.

prstein
- 26th May 2013, 02:42
Hello Art,

I am cautiously encouraged...8v) A quick google indicates that BT keyboards use the HID protocol. I've only used SPP (serial port profile), and SPP may be the problem with Apple. (See http://support.apple.com/kb/HT3647)

It appears the SparkFun sells a BT module that is hand solderable, and supports both HID and SPP: https://www.sparkfun.com/products/10823.

Might have to get one of those myself!

Best Regards,
Paul

Art
- 26th May 2013, 03:40
BT keyboards WERE closed, but Apple opened up to them around iOS 4 (don't quote me on that though).
The iPad would have created the expectation that a BT keyboard be functional.
BT keyboards definately work now... it's how the iCade joystick interacts with iDevices.
The iDevice thinks the iCade is a BT keyboard... I'm certain of this.

When you move the joystick UP, it sends a "W" character just as a keyboard would,
and it's up to the app developer who wants to support the iCade joystick to interpret
the characters as joystick movement (but there are already open libraries for this).
I'm sure you could just use a BT keyboard to play games with iCade support if it
weren't for the fact that the iCade sends another character when any button is released.

You can get MFI approved BT GPS devices, but that's different.
I just want to dodgy up my own GPS to send via any old keyboard chip.
NMEA sentences don't use any non-ASCII values, so everything the GPS sends
can be represented by keyboard key strokes.
It's a pity a fully functional serial port couldn't work this way.

The new Air Console device looks promising though.

I'm glad I've inspired you.
Maybe you will do the work of testing the thing out, and I'll definitely follow! :D

I do have info on the deal with Apple supported serial adapters such as those
supplied by Redpark for use with the Get Console app.
It's bad :( No other Apple approved developer can use it, even if someone totally figures it out!
There is another serial cable for controlling telescopes, and it's more or less the same hardware
with some firmware mod just to make the distinction between that cable, and any other, just so
the Redpark cable, and Skywire cable are not interchangeable... otherwise they certainly would be.
Sux eh?

The Redpark one works well with it's app.
I can even program a new message on my 144 LED message scroller I posted here,
using nothing other than my iPhone!
Totally sux that the s port is right there, but you can't use it.

prstein
- 26th May 2013, 05:37
I'm glad I've inspired you.
Maybe you will do the work of testing the thing out, and I'll definitely follow! :D

Ha! I was hoping that *you* would do testing and figure it out for *me*!

And please don't tell my wife I may have admitted to being wrong about something...wouldn't want to raise her expectations.

Best Regards,
Paul

Art
- 26th May 2013, 07:13
Lol, if you have an iPad, and the USB camera connection kit,
it also works with wired USB keyboards right out of the box.. totally undocumented.
Some keyboards fail because they require too much power.

Art
- 5th June 2013, 09:03
I had a look at the data sheet, oh my, I think for a one-of project it would be simpler
to destroy the smallest bluetooth keyboard I can find.
There is an IC about that can make the keyboard switch connections directly,
I think it's called a lateral switch, and an IC has ten of them.

It might pay to just connect the numeric keys and enter, and just send all data as one checksummed slab of numeric data.
If I make this thing, it will end up a rather large GPS. The GPS is a serial GPS mouse that requires power.

Charlie
- 5th June 2013, 12:43
Hi Art. I'm not interested in starting a platform war here, but if you are keen to develop apps, particularly with custom hardware, you might find Android less painful as the platform is pretty much completely open. I programmed a PIC to measure temperature with a DS18B20, send serial data to a VERY cheap RS232 Bluetooth adapter, receive and display on my phone with an app I wrote... all in just a couple hours, and everything done in Basic. The iPhone is cool and was the first in the space, but there is little to distinguish the platforms today, other than openness (and cost). You might want to have a look at least, and come to your own conclusion.

Art
- 5th June 2013, 13:17
It is my intention to write for both,
but right now I'm already committed, and have apps in their app store.

This project is just a little thing for me personally.