DatasheetsPDF.com

TB055

Microchip Technology
Part Number TB055
Manufacturer Microchip Technology
Description PS/2 to USB Mouse Translator
Published Sep 26, 2014
Detailed Description TB055 PS/2® to USB Mouse Translator Author: Reston Condit Microchip Technology Inc. IMPLEMENTATION Hardware The PS/2 po...
Datasheet PDF File TB055 PDF File

TB055
TB055

Overview
TB055 PS/2® to USB Mouse Translator Author: Reston Condit Microchip Technology Inc.
IMPLEMENTATION Hardware The PS/2 port is a 6-pin DIN.
Only four pins are used: • • • • Ground Power Clock Data OVERVIEW This Technical Brief details the translation of a mouse to a USB mouse using the PIC16C745/765.
The PIC16C745/765 is Microchip’s low-speed USB microcontroller.
All of the USB descriptors for the mouse translator are listed in the tables in Appendix A: “Device Descriptors”.
A detailed byte-by-byte description is given for each descriptor to assist USB peripheral designers in understanding USB descriptors.
For the basics of USB descriptors, refer to TB054, “An Introduction to USB Descriptors with a Game Port to USB Game Pad Translator Example”.
PS/2® The power and ground pins are tied directly to VDD and VSS of the microcontroller.
The clock and data pins are connected to RC0 and RC1, respectively, via current limiting resistors.
The clock is driven by the PS/2 mouse regardless of the direction of the transaction.
Figure 1 shows the complete system.
Note: This Technical Brief is the second in a series of five technical briefs.
This series is meant to familiarize developers with USB.
For the best understanding of USB, read the briefs in order: TB054, TB055, TB056, TB057 and TB058.
FIGURE 1: PS/2® TO USB MOUSE TRANSLATOR HARDWARE DIAGRAM(1) C1(2) PIC16C745/765 OSC1 C2(2) XTAL PS/2® Female 100Ω 6 MHz OSC2 R1 VUSB C3 1.
5k USB Cable DD+ VSS* DD+ GND +5 VDC 200 nF Host 6 4 2 5 3 1 5 3 4 1 Clock Data RC0 RC1 C4 0.
1 µF VDD* Note 1: There are two VSS and VDD pins on PIC16C765.
2: C1 and C2 values selected according to crystal load capacitance.
 2004 Microchip Technology Inc.
DS91055C-page 1 TB055 Software PS/2 DATA FORMAT Before explaining how PS/2 mouse data is translated to USB, it is necessary to touch upon the PS/2 data format.
Data is sent via PS/2 one byte at a time regardless of direction, host-to-device or vice-versa.
The data has the following form:...


Similar Datasheet


@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site. (Privacy Policy & Contact)