Keil MCB167-NET, Руководство пользователя

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MCB167-NET Board User’s Guide 17
PAL Equations
This following lists the PAL equations for the 20V8 logic device at IC12.
;PALASM Design Description
;---------------------------------- Declaration Segment ------------
TITLE
GAL for MCB167NET Prototype board
PATTERN Decode Logic for Ethernet Controller
REVISION 1.0
AUTHOR
Hans Schneebauer
COMPANY Keil Elektonik GmbH
DATE 09/30/99
CHIP IC15 PALCE20V8
;---------------------------------- PIN Declarations ---------------
PIN
1 UNUSED1 COMBINATORIAL ; INPUT
PIN 2..6 A[8..12] COMBINATORIAL ; INPUT
PIN 7 /RD COMBINATORIAL ; INPUT
PIN 8 /WRL COMBINATORIAL ; INPUT
PIN 9 /WRH COMBINATORIAL ; INPUT
PIN 10 /RSTOUT COMBINATORIAL ; INPUT
PIN 11 /CS2 COMBINATORIAL ; INPUT
PIN 12 GND ; INPUT
PIN 13 UNUSED2 COMBINATORIAL ; INPUT
PIN 14 UNUSED3 COMBINATORIAL ; INPUT
PIN 15 RESET COMBINATORIAL ; OUTPUT
PIN 16 /IOW COMBINATORIAL ; OUTPUT
PIN 17 /IOR COMBINATORIAL ; OUTPUT
PIN 18 /MEMW COMBINATORIAL ; OUTPUT
PIN 19 /MEMR COMBINATORIAL ; OUTPUT
PIN 20 AEN COMBINATORIAL ; OUTPUT
PIN 21 /REFRESH COMBINATORIAL ; OUTPUT
PIN 22 /SBHE COMBINATORIAL ; OUTPUT
PIN 23 UNUSED4 COMBINATORIAL ; INPUT
PIN 24 VCC ; INPUT
;----------------------------------- Boolean Equation Segment ------
EQUATIONS
RESET = RSTOUT
SBHE
= WRH + RD
AEN = 0
REFRESH = 0
IF (A[11..8] = #b0011) THEN ; If in Range 0300H - 03FF -> IO Interface
BEGIN
IOR = RD * CS2
IOW = (WRL + WRH) * CS2
MEMR = 0 ; MEMR always inactive
MEMW = 0 ; MEMW always inactive
END
ELSE ; If in Range 0 - 02FF or 0400 - 0FFF
BEGIN ; -> Memory Interface
IOR = 0 ; IOR always inactive
IOW = 0 ; IOW always inactive
MEMR = RD * CS2
MEMW = (WRL + WRH) * CS2
END
;-------------------------------------------------------------------