DV164126 Microchip Technology, DV164126 Datasheet - Page 26

• Manufacturer Part Number: DV164126
• Description: KIT DEVELOPMENT USB W/PICKIT 2
• Manufacturer: Microchip Technology

Specifications of DV164126

• Main Purpose: Interface, USB 2.0 Slave
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: PIC18F13K50, PIC18F14K50
• Primary Attributes: Full Speed (12Mbps), MCU Based
• Secondary Attributes: 4 Labs: Enumeration, HID Mouse, HID Keyboard, CDC Serial Emulator
• Silicon Manufacturer: Microchip
• Silicon Core Number: PIC18F14K50, PIC18F13K50
• Core Architecture: PIC
• Core Sub-architecture: PIC18
• Silicon Family Name: Piccolo
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

Low Pin Count USB Development Kit User’s Guide
2.6
DS41356B-page 22
PROJECT LAB 3 (HID KEYBOARD)
12. Disconnect the PICkit 2 and connect the Low Pin Count USB Demo Board to the
13. The device should enumerate and the LEDs on the board flash in accordance
14. Pressing the push button should start and subsequently stop the mouse pointer
The user is encouraged to experiment with this application by altering the length of time
that the mouse pointer moves until a directional change or altering the values in the
ROM signed char dir_table[]={-4,-4,-4, 0, 4, 4, 4, 0};
In this lab, the PIC18F14K50 is implemented as a HID keyboard device. The ADC
peripheral is configured to perform conversions on the voltage level present on the port
pin connected to the potentiometer on the Low Pin Count USB Development Board.
The value in the ADC result register is then used to create a numeric value between 4
and 29 that will display an alphabetic character between ‘a’ and ‘z’ on the Host PC
screen (refer to HID Usage Tables document Section 10 “Keyboard/Keypad Page”
(0x07)). As the potentiometer is rotated, the character outputted to the screen will
change accordingly. The user should note that this application could be applied to a
data logger application with the potentiometer on the Low Pin Count USB Development
Board simulating a mixed signal interface to monitor an off-chip application. The data
generated and transmitted via the USB could be connected and interpreted by a
Graphical User Interface on the Host PC to monitor real-time application behavior or
used to store essential data for later analysis.
2.6.1
The keyboard()is the user-defined function that is called from ProcessIO() to
parse the data received from the ADC module, transmit the numeric value along the
USB and display the appropriate character on the screen. This function is implemented
as a state machine. The state diagram for this function is shown in Figure 2-5.
A word of caution, this HID device has the potential to be harmful if a key combination
is used that initiates a Windows
the transmitting buffer contains only keycodes that the user is confident will not
produce any harmful key combinations.
Host PC port.
with the BlinkUSBStatus() discussed in the self-directed course.
moving in a circle on the Host PC screen.
Overview of the HID Keyboard Firmware
®
shortcut. Great care should be taken to ensure that
CAUTION
CAUTION
© 2009 Microchip Technology Inc.