DM163010 Microchip Technology, DM163010 Datasheet - Page 15

• Manufacturer Part Number: DM163010
• Description: BOARD DEMO PICDEM USB
• Manufacturer: Microchip Technology

Specifications of DM163010

• Processor To Be Evaluated: PlC16C745/765
• Interface Type: USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

©
2001 Microchip Technology Inc.
By following these steps, the hardest part of the development can be com-
1.5.1.1
When you start developing your application, make sure that your data require-
1.5.1.2
The most difficult part of any USB application is determining what the device
1.5.1.3
The report descriptor allows HID devices to communicate to the host. The
1.5.1.4
The next step is to add your specific hardware and software. Carefully study
pleted right away on known good hardware (the PICDEM™ USB). After the
application is communicating to the PC correctly, the application specific
hardware and software can be developed.
ments fit the USB specification. A low speed device is limited to 2 channels of
communication (end points), with each channel limited to 800 bytes per
second. The most common mistake is to assume that the entire 1.5 Mbs is
available for your application.
descriptors should be. Every USB device communicates its requirements to
the host through a process called enumeration. During enumeration, the
device descriptors are transferred to the host and the host assigns a unique
address to the device. The descriptors are described in detail in Chapter 9 of
the USB 2.0 specification. Bundled with the USB tools CD, a descriptor tool is
provided to assist you in creating your own descriptors.
report descriptor communicates the exact packet format of your data. This is
where the PC determines how large your packets will be. Report descriptors
range from the very specific (a multi-function joystick) to the very generic (a
specialized communications device for your application). Tools are available
to assist you in creating your report descriptors. The descriptor tool, which is
bundled in your kit, will have report descriptor capabilities with a future revi-
sion. After the report descriptor is written make sure that it is working with the
PC by using PC analysis tools. These are available from the USB-IF web site
for the PC, and Apple Computer for Macintosh machines. Use simple
counters and other dummy data to test report descriptor traffic. After the com-
munications link is working, it will be much easier to develop the rest of the
application.
the schematic in this guide and use the same circuitry for the USB connec-
tions. The circuitry will never change for this device. When your hardware is
built, you can be confident that your communications code will work because
it was developed on the development system with the same communications
circuitry.
Getting Started with the PICDEM™ USB
Describing the Application
Creating the Descriptors
Developing the Rest of the Application
Debugging the Report Descriptor
DS41174A-page 11