Keil MCB517AC, User Manual

Page: 30 / 61

24 Chapter 3. Hardware
BEGIN
0: BEGIN ; No Banking
A_P[15] = A15
A_P[16] = 0
A_P[17] = 0
A_R[15] = A15
A_R[16] = 0
A_R[17] = 0
A_R17 = 0
END
1: BEGIN ; 2 Banks with a 1MBit * 8 Eprom
A_P[15] = A15 * /P6[5]
A_P[16] = A15 * P6[5]
A_P[17] = 0
A_R[15] = A15
A_R[16] = 0
A_R[17] = 0
A_R17 = 0
END
2: BEGIN ; 4 Banks with a 2MBit * 8 Eprom
A_P[15] = A15 * /P6[5]
A_P[16] = A15 * P6[5] * /P6[6] +
A15 * /P6[5] * P6[6]
A_P[17] = A15 * P6[5] * P6[6]
A_R[15] = A15
A_R[16] = 0
A_R[17] = 0
A_R17 = 0
END
3: BEGIN ; 7 Banks with a 2MBit * 8 Eprom
A_P[15] = A15 * /P6[5]
A_P[16] = A15 * P6[5] * /P6[6] +
A15 * /P6[5] * P6[6]
A_P[17] = A15 * P6[5] * P6[6] +
A15 * P6[7]
A_R[15] = A15
A_R[16] = 0
A_R[17] = 0
A_R17 = 0
END
END
END
;-------------------------------------------------------------------
This following lists the PAL equations for the 20V8 logic device at IC22.
;PALASM Design Description
;---------------------------------- Declaration Segment ------------
TITLE GAL for MCB517 Prototype board IC22
PATTERN Decoder and Boot Logic
REVISION 1.0
AUTHOR Hans Schneebauer
COMPANY Keil Elektonik GmbH
DATE 10/20/96
CHIP IC22 PALCE20V8
;---------------------------------- PIN Declarations ---------------
PIN 1..8 A[8..15] COMBINATORIAL ; INPUT
PIN 9 /PSEN COMBINATORIAL ; INPUT
PIN 10 /RSTOUT COMBINATORIAL ; INPUT
PIN 11 /RD COMBINATORIAL ; INPUT
PIN 12 GND ; INPUT