USB stacks for embedded micros

If you are not familiar with the details of interfacing to USB you may find our Embedded USB tutorial helpful.

Using a USB software stack allows your embedded application to....

Device Stack	Link to a PC that can control your device and exchange data with it using USB pipes
	Appear to a PC as a Thumb Drive, Serial device or a Mouse
Host Stack	Control a network of up to 127 devices
	Use a Thumb Drive as data storage that is then PC readable
	Use USB devices that conform to the USB standard ( eg Keyboard, Printer, Serial or Mass Storage)
OTG	The On-The-Go standard allows your device to decide if it is going to act as a Slave or as the Networks Host

New product range to receive literature  fill in request
 

These software stacks are from Micro Digital and they may be purchased separately to keep cost low or together for use in OTG controlled dual role devices. FAT32 file handling software is available for creating Thumb Drive based applications.

Written in ANSI C for portability.

Available for ARM, ColdFire, PPC and x86 processors

Fully compliant with the USB 2.0 specification

Support all 4 data transfer mechanisms ( Control, Bulk, Isochronous and Interrupt)

Run standalone, under smx or portable to other OSs

Support a wide range of on and off chip USB interfaces

Class drivers are available for Mass storage, HID, Printers, Audio, Modem, Hubs and Serial devices

Evaluation versions are available for a number of popular boards

New interfaces are being added rapidly so if you do not see the one you need do call us

The Code space figures are for a CISC processor RISC is typically ~20% greater
Data space for the Host stack is much larger for UHCI interface

Interfacing to a Thumb Drive / Memory Stick

The most common question we get is "What do I need if I am going to interface my micro to a Thumb drive ? " but often the problem needs some clarification.

There are two possible scenarios.....

1) The questioner is building a product that already has some local storage and the device will itself be connected via USB to a PC and will appear to the PC as a Thumb Drive.  To do this you need a Device stack and a FAT file system.

2) The questioner is building a product that requires some mass storage which can also be used as a mechanism for transferring data from or too a PC.  USB on the product enables cheap and portable Thumb Drives to be used.  To do this you need a Host stack and FAT32 File System 

The smxFS file system provides a way of handling mass storage that is Windows compatible (FAT16,32,VFAT) including long names. It uses the "standard" C API (fopen,fread etc) for ease of programming and is re-entrant so safe for use on multi-tasked embedded systems. Its code and data  footprints are ~12K/7K respectively.  Depending on the USB Host controller we have timed writes at 300KBytes - 7Mbytes/sec and reads at 300KBytes - 10MBytes/sec

We have packages that include Host or Device stacks integrated with FAT file systems to simplify adding this functionality to USB enabled embedded systems.

Demos available on common EVBs

We have a large number of preconfigured demonstration systems that run on the most popular evaluation boards please copy the board number and use our contact page to tell us which you would like and we will be happy to supply you with a copy