PCB Help & General Circuit Design

[bogusbob1234]

Working on Devoloping a custom Device for the GP2x handheld.

It's uses are a wireless internet provider an SD storage device and have portable power. It Needs to act as a USB hub with these devices "plugged" in. (will be hardwired)

Heres what I need to know. SD to USB.... What do you need , IE.. controllers what else? Also can be purchased in small quantites at mouser or digikey.

 

[MacGyverS2000]

Do you have a specific question? We're not here to put together a design for you... unless you intend to hire one of us.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[itsmoked]

Agreed Dan.

Also you need the file system firmware. SD's want to talk a certain way about the file structure. It would be easiest to locate a package that lets you use SPI to talk to an SD controller that talks to the actual SD. Then you can use any SD, and when plugged into a PC it can directly read and write the same files.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[GonzaloEE]

Agreed. You will hardly find whole projects here for free.

Anyway, you may start with a USB controller, a CPU and your SD memory. Allegro has some SPI/USB converter ICs to pass USB traffic to CMOS levels.
For CPU, you might use any cheap PIC, some AVR/ATmel, ARM or something that suits better your design.
As said before with SD memories, you need some firmware 'drivers' on CPU to drive it and deal with filesystem.

Regards,
Gonzalo

 

[hcooperCO]

You can do a USB to SD interface in a single PIC procesor, and yes it can be bought at digikey.

Course you will need some software. But its out there...just need to look for it.

 

[GonzaloEE]

You may also try the FT232BM from FTDI, an USB-to-serial converter IC. It could save you some code lines (USB driver) for your uC.

Good Luck!
Gonzalo

 

[automatic2]

you'll need a usb peripheral controller, and software to implement the mass storage protocol. Luckily, most manufacturers build single solution chips. I use the 8051 Atmel devices. They also provide plenty of software examples for USB implementation.

You might want to consider the compact flash for speed reasons.