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Which CPU to use?
4

Which CPU to use?

Which CPU to use?

(OP)
Hi all,

I'm stuck in a project where we need to build a fleet tracking device, based on some embedded processor.
Briefly speaking, the device will be attached to the car's dashboard.  It will keep a database with a number of geographical points, and it should play an MP3 file if the car passes near one of this locations.
To put things harder, the data base would be updated either through a cellular link, or a close range Wi-Fi/Bluetooth link.

I offered something with SBC, even a mobile phone packed together with other h/w in the same enclosure, though the client wants an embedded device with a custom board.
Considering I will need an OS, file system, MP3 decoding, and enough room for the GPS database and device drivers. I think a microcontroller is too basic for this.

OK, the question: Can you suggest me some CPU with good s/w support for OS and file system?
Assume I already have a GSM, GPS nd Wi-Fi hardware, enough external RAM/ROM, and database update is done though an existing web or FTP client.

I'd appreciate any help though I'm not familiar with high-level CPUs.  

RE: Which CPU to use?

Check out Freescale, QualComm and TI....

RE: Which CPU to use?

I think your client needs his head examinind. LOL

This is a non trivial exercise.   He really should find something off the shelf as a starting point.  Be it a cellphone/MP3 player or a WiFi tablet computer or a PDA.

But otherwise.
I'd reach for an ARM, or a dsPIC, or a 32bit PIC,- things with lots of memory and code space.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Which CPU to use?

I seem to recall that GPS chip vendors seem to favor WinCE as far as drivers go, so you may want to look at chips that will support this. I'd probably also suggest an ARM processor.

RE: Which CPU to use?

(OP)
Thanks guys. I'm going with an AVR with Linux support.

GonzaloEE

RE: Which CPU to use?

(OP)
In fact I've decided using a 32bit AVR. WinCE is certainly a good approach with good support, though my firmware team told me they feel more 'at home' with Linux.

Thanks,
GonzaloEE

RE: Which CPU to use?

Hiya-

There is a little linux product called gumstix that might
provice some basis for support.  It is a "daughterboard" approach.  The gumstix can be bought for an OEM application and has the processor (An Intel 266?) and enough ram and rom on board and I believe an I2C interface connection for basic I/O.

Opps. Sorry it's a MarvellĀ® PXA270 with XScale CPU.

More info at:

http://www.gumstix.com/platforms.html

I haven't used it yet, just looked at it.  They have little development systems that could get the software types started out and running.

Hope this helps.

  Cheers,

   Rich S.

RE: Which CPU to use?

(OP)
Thanks Richs. Those boards and CPU speed look fine for this automotive scenario.
I'm actually managing the project, so I have little input at such a technical level.  Anyway, I'm forwarding your valuable suggestion.

Thanks,
GonzaloEE  

RE: Which CPU to use?

Hi GonzaloEE-

Glad to help!  We are all in this together!  Sometimes the group input is very valuable. I know I appreciate it.  People like ItSmoked and you (and many, many others) are all certainly great resources!

Keep us posted on progress too!

 Cheers,

   Rich S.

RE: Which CPU to use?

(OP)
Agreed.  The main value of this site is just that: quick technical support without the mess of contracting consultants offline ;)

PS: Apologies to any consultants here, I respect their valuable knowledge and careers :)

Thanks,
GonzaloEE

RE: Which CPU to use?

Hiya GonzaloEE

I ran across this CPU on the piclist as off topic. The thread was "[OT] Smallest Linux Computer".  I have had no experience with this company nor the CPU mentioned in it.

But, going to the link listed below and looking at the datasheet, it might have enough for your needs running uClinux which is a non multitasking varient of linux for the smaller CPUs without memory management units (MMUs).

It *MIGHT* be something to look at, but I don't know if it's a real product, or vaporware.  I don't know if it's a flash in the pan that will be unavailable in a year or if it is second sourced.

It *IS* a 256 ball grid array (BGA) and it *IS* all on one chip.  At least it's interesting.

The link is:
 http://www.axis.com/products/dev_etrax_100lx_mcm/index.htm

  Cheers,

   Rich S.

RE: Which CPU to use?

Just in case you haven't considered it, for operating systems, you might want to consider uCOS-II.  It is a very light weight, multi threaded operating system that is relatively easilly ported to different platforms.  If you are using a PC based system, though, the porting won't be an issue for you.

I am not an expert on this OS, but I understand that it has been well tested and proven and even has an FAA and (and possibly nuclear application) suitability rating.  On top of all that, it is relatively inexpensive, especially in comparison to the "big" players.

RE: Which CPU to use?

(OP)
Thanks, Noway2. The development is currently out of my hands. I'm afraid the s/w guys are just advancing with some sort of ARM+Linux approach.
Your suggestion sounds good, though. I'll save it for future projects.

Regards,
Gonzalo

RE: Which CPU to use?

That one (the AXIS chip) has been around for quite a while. I remember seeing it years ago.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: Which CPU to use?

(OP)
Thanks Rich and Gunnar,  I'm forwarding your hints to my dev. team. The ETRAX approach is very interesting, specially for its small footprint.

The project is a fleet management system, with the added-feature that mobile devices (attached to the vehicles) must play some MP3 files while on the road, under a complex mix of location and vehicle speed conditions.
The assigned routes and audio files are uploaded to each vehicle from a fixed host in a parking garage, through a low-range wireless link (WiFi, bluetooth, etc.)
There are some 500 points per vehicle, so I'm figuring out a huge database at the host, and almost 50MB of 'music' per vehicle.
 
I have a telecom/networking background, so I suggested setting up a network, with the host and vehicles working much like any office LAN, with a fixed server, and vehicles acting like mobile laptops. This allowed us to use a more  friendly network enviroment, file sharing, etc.
The s/w guys wanted to re-cycle some of their Linux code and device drivers from other projects, where they also deployed web-servers into ARMs.  Hope this sort of 'code bank' will be enough portable to be applied on the ETRAX board.

Thanks for your suggestions!
Gonzalo





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