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[on:]

Hello,

i know, there is the GSP-Shield for about $55.

I recently saw this article about the iPhone:
http://www.isuppli.com/Teardowns/News/Pages/iPhone-4-Carries-Bill-of-Materials-of-187-51-According-to-iSuppli.aspx

According to them, the iPhone does have a Broadcom BCM4750 GPS-Module for about $1.75.

I couldn't found a datasheet yet, but the Broadcom Website says:
"Host communication via two-wire UART, I²C-compatible Broadcom Serial Control (BSC), or SPI with baud rates as low as 9.6 Kbps"

This should be possible for the arduino, shouldn't it?

[Reply #1 on:]

Nobody?

[Reply #2 on:]

These models can provide 10 Hz positions updates, over serial interface.

This thread might be a starting point.

[Reply #3 on:]

Broadcom BCM4750 GPS-Module for about $1.75

The article doesn't explicitly state whether that price is for quantities of one or for commercial quantities of tens or hundreds of thousands. I presume it is commercial quantities.

Pete

[Reply #4 on:]

You are right, el_supremo!
Even though the price might be for commercial quanitites, i assume single quanititys would be under $10, which would be a real alternative to the GPS shield.

We just have to figure out:

- Who is selling them?

- Whats exactly in the datasheet?
(Does it return a position over serial, or complex raw satellite data?)

I took a few google searches, but couldn't find something useable yet.

[Reply #5 on:]

This appears to be the RF receiver, not a full GPS engine.  The website says:

Broadcom provides a software library that realizes the GPS navigation solution in the host using minimum resources and with no real time requirements.

So, it's RF and maybe DSP hardware, but it leaves it to the host microcontroller to do the heavy lifting.  This is probably why the battery dies so fast when I use the GPS on my iPhone.   This sort of solution makes sense if you care less about power consumption or development time than the per-unit production price.

An 8 bit microcontroller like the arduino doesn't have enough horsepower to do the heavy lifting.

-j

[Reply #6 on:]

These [Locosys] models can provide 10 Hz positions updates, over serial interface.

SparkFun sells the Locosys LS20031 module for $59.95.  The lowest retail I can find is $49.00. Pretty far from $1.75.