Sample: ExternalAccessory Framework

[sleepless]

The attached sample shows how you can read NMEA GPS data from the Tom Tom Car Kit.

I needed to get at the raw GPS data rather than relying on the Core Location framework's highly filtered data.

Since it took a bit of noodling to figure this out, I thought others might find this useful as a general example on how to get at data via the accessory port or via Bluetooth.

Note: This works only with Made for iPod accessories; you cannot get a serial stream from a random Bluetooth or cable accessory... Sadly

[boostedz06]

thanks

[dp1098]

Your code works great but I am having trouble making the GPS data available to other applications vice the internal A-GPS. I know there is a way to take external location data and have it published to other apps using the Core Location framework - I just don't know how.

Any thoughts or ideas would be greatly appreciated. Thanks in advance.

[thephotographer]

sleepless, Can you 100% confirm that you can only use made for ipod accessories? is there really no way to use any gps receiver via bluetooth?Did you find that in apple documentation or via personal experimentation and experience?

I have had someone ask me about making an iPad application that can use a gps input from an external GPS receiver. It cant be a made for ipad gps receiver such as tomtom due to accuracy required. the customer needs the application to be accurate to about 2cm. the gps receivers we will use can output the gps stream in a number of different formats, out via bluetooth, serial, or ethernet.

i was thinking as a last resort if bluetooth cant work, i could plug the gps receiver into a wifi access point and have the ipad connect to the nmea stream over wifi. hopefully there wont be much latency

[dcool]

Originally Posted by thephotographer

sleepless, Can you 100% confirm that you can only use made for ipod accessories? is there really no way to use any gps receiver via bluetooth?Did you find that in apple documentation or via personal experimentation and experience?

With iOS 5.1, you can use CoreBluetooth.framework without MFI licence, but it works only with Bluetooth 4.0 (BLE) hardware.

There is very interesting article about it:
CoreBluetooth, Low-Energy connector framework for iOS5 - iOS-Blog