U15 address decoder – Zilog eZ80F92 User Manual
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eZ80F92 Development Kit
User Manual
Appendix A
UM013911-0607
77
//Flash enabled if this is
0
//wire nDIS_FL = (nFL_DIS) ? ~nEXP_EN : ~(nFL_DIS);
wire nDIS_FL = nFL_DIS & nEXP_EN; //if either of them is 0
Flash
//is disabled
assign nCS_EX = (nEX_FL_DIS) ? nEXP_EN : ~(nEX_FL_DIS);
assign nL_RD =
~((nmemen1==0)|(nmemen2==0)|(nmemen3==0)|(nmemen4==0)|(nEM_EN=
=0)|(nCS_EX==0));
assign nmemen4 = ~((nCS2==0)&({A7,A6,A5,A4,A3}==5'h17));
assign nmemen3 = ~((nCS2==0)&({A7,A6,A5,A4,A3}==5'h16));
assign nmemen2 = ~((nCS2==0)&({A7,A6,A5,A4,A3}==5'h15));
assign nmemen1 = ~((nCS2==0)&({A7,A6,A5,A4,A3}==5'h14));
assign nEM_EN =
~((nCS2==0)&({A7,A6,A5,A4,A3,A2,A1,A0}==8'h80));
endmodule
U15 Address Decoder
`define
anode
8'h00
`define
cathode
8'h01
`define
latch
8'h02
// FOR eZ80 Development Platform Rev B
// This PAL generates signals that control Expansion
// Module access, LED and Port A emulation
// This device is a GAL22LV10-5JC (5ns tpd) or
// equivalent with Package = 28 pin PLCC
//
//