User`s guide

Does the device need to be backward-

compatibility with an existing host PC

application?

Use the device class for which

the original host application

was designed.

Decide between CDC and MSC based on criteria in Table I.

YES

Is the device a mouse, keyboard,

or other peripheral in which the

host operating system recognizes

and interacts with the device?

Use HID. (In MSP430's API,

µ^,/-d]]}vo_)

YES

Is the required bandwidth under 64KB/

sec?

Use HID. (In MSP430's API,

µ^,/-]_, to create

an unformatted datastream.)

YES

Does the device type

have a strong association with a

particular class? (PHD class for medical; CCID

class for smart card; Imaging

class for cameras; etc.)

Use the expected device class.

YES

dZo]]}vv}v]^Pvoµ}_.

www.ti.com

MSP430 USB Software Design

Sometimes the choice of device class is clear. In other cases, the application can be considered general

purpose, giving the developer options. Although there are many ways to approach this decision, one way

is shown in Figure 11.

Figure 11. Example Process for Deciding on a USB Device Class

For general-purpose use, HID-Datapipe should be considered, because of its combination of silent loading

on the host (easy for the end user) and its small footprint and simplicity on the MSP430 MCUs, which

speeds development. Coding of a corresponding host application is made easier with the MSP430 Java

HID Demo App.

SLAA457A–September 2013–Revised May 2014 Starting a USB Design Using MSP430™ MCUs

Submit Documentation Feedback