Interlink Electronics VersaPad USB - Manual (Page 18)

USB VersaPad®
Integration Guide
www.interlinkelectronics.com
16
7.0 USB Information
Communication from the host to the microprocessor is done via USB and:
 Uses the low speed USB standard
 Is compatible with any USB 1.1 or 2.0 host
 Enumerates as a HID device
 Uses the standard Windows mouse driver
The microprocessor reports data to the host at a rate of 50 reports/sec.
7.1 Device PID and VID
 IC’s Product ID (PID): 0x0001
 Interlink
Electronics’ Vendor ID (VID): 0x214A
7.2 Data Packet
The data packet from the chip is organized as.
 Byte
0
o Bit 0 is the Left Button status
o Bit 1 is the Right Button status
o Bit 2 is the Middle button status
 Byte 1 reports the X direction. The values range from -127 to +127 counts.
 Byte 2 reports the Y direction. The values range from -127 to +127 counts.
7.3 USB Suspend Mode
The module will respond to suspend command from the host by entering ‘sleep mode’ until
awakened by the host. While in suspend mode, the chip will go into a low current draw
mode.
7.4 Operating Voltage and Current
The USB VersaPad is bus powered; therefore, it operates at 5V. Under normal operation,
the device draws approximately 15mA. During suspend mode the chip enters a low current
mode. In this mode the chip will draw no more than 25nA.