Using The Ps/2 Keyboard Interface - XESS XStend Manual

019- NET A4
020- NET A5
021- NET A6
022- NET A7
023- NET A8
024- NET A9
025- NET A10
026- NET A11
027- NET A12
028- NET A13
029- NET A14
030- #
031- # XS95 BOARD RAM CONTROL PINS
032- NET OE_
033- NET CE_
034- #
035- #
036- # XSTEND BOARD CONNECTIONS
037- #
038- # VGA CONNECTIONS
039- NET VSYNC_
040- NET HSYNC_
041- NET RED1
042- NET RED0
043- NET GREEN1
044- NET GREEN0
045- NET BLUE1
046- NET BLUE0
047- #
048- # PUSHBUTTON SWITCH CONNECTIONS (ACTIVE-LOW)
049- NET PUSH_RESET_

3.3 Using the PS/2 Keyboard Interface

This example creates a circuit that accepts scan codes from a keyboard attached to the PS/2
interface of the XStend Board and displays it on the LEDs. In addition, if a scan code for one of
the keys '0'—'9' arrives, then the numeral will be displayed on the right LED display of the
XStend Board. The ABEL code for this example is shown in Listing 19; Listing 20 and Listing
21 show the UCF files for using the XS40 and XS95 Boards with the XStend Board,
respectively.
The design files for this example should be found in C:\XST-PROJ\EXP3. The steps for
compiling and testing the design using an XS40 combined with an XStend Board are as follows:
• Synthesize the ABEL code in the EXP3.ABL for an XC4005XL FPGA.
• Compile the synthesized netlist using the EXP3_40.UCF constraint file.
• Mount an XS40 Board in the XStend Board and attach the downloading cable from the
XS40 to the PC parallel port. Apply 9VDC though jack J9 of the XS40. Place shunts on
jumpers J4, J7, and J8 to enable the LEDs. Place a shunt on jumper J11 to keep the XStend
codec disabled. Attach a keyboard to the PS/2 connector of the XStend Board.
LOC=P79;
LOC=P82;
LOC=P83;
LOC=P84;
LOC=P58; # UPPER BYTE OF ADDRESS
LOC=P56;
LOC=P54;
LOC=P55;
LOC=P53;
LOC=P57;
LOC=P61;
LOC=P62; # ACTIVE-LOW OUTPUT ENABLE
LOC=P65; # ACTIVE-LOW CHIP ENABLE
LOC=P24;
LOC=P15;
LOC=P14;
LOC=P18;
LOC=P17;
LOC=P19;
LOC=P23;
LOC=P21;
LOC=P10;