module top (
input IACK,
input RW,
input REROM,
input AS,
input A12,
input A13,
input A14,
input A15,
input A16,
input A17,
input A18,
input A19,
input A20,
input A21,
input A22,
input A23,
output ~q7,
output ~q6,
output ~q5,
output ~q4,
output ~q3,
output ~q2,
output ~q1,
output ~q0
);
assign ~q7 = (RAM Select)
(~IACK & REROM & ~AS & ~A21 & ~A22 & ~A23)
;
assign ~q6 = ($FDF000 to $FDFFFF) (Peripheral Select)
(~IACK & REROM & ~AS & A12 & A13 & A14 & A15 & A16 & ~A17 & A18 & A19 & A20 & A21 & A22 & A23)
;
assign ~q5 = ($FD0000 to $FD3FFF) (EEPROM Select)
(~IACK & REROM & ~AS & ~A14 & ~A15 & A16 & ~A17 & A18 & A19 & A20 & A21 & A22 & A23)
;
assign ~q4 = (External Peripherals Enabled)
(~A21 & ~A22 & ~A23) | (RAM Space)
(A17 & A18 & A19 & A20 & A21 & A22 & A23) | (ROM Space)
(~A14 & ~A15 & A16 & A18 & A19 & A20 & A21 & A22 & A23) | (EEPROM Space)
(A12 & A13 & A14 & A15 & A16 & A18 & A19 & A20 & A21 & A22 & A23) | (Peripheral Space)
(AS) |
(~REROM) |
(IACK)
;
assign ~q3 = (Unused)
(~IACK & REROM & ~AS & ~A12 & A13 & A14 & A15 & A16 & ~A17 & A18 & A19 & A20 & A21 & A22 & A23)
;
assign ~q0 = (ROM Select) ($FE0000 When Not REROM, $000000 when REROM)
(~IACK & RW & ~AS & A17 & A18 & A19 & A20 & A21 & A22 & A23) |
(~IACK & RW & ~REROM & ~AS & ~A17 & ~A18 & ~A19 & ~A20 & ~A21 & ~A22 & ~A23)
;
endmodule
