General Array Logic Equations; U10 Address Decoder - ZiLOG eZ80L92 User Manual

Appendix A

General Array Logic Equations

This appendix shows the equations for disabling the Ethernet signals pro-
vided by the U10 and U15 General Array Logic (GAL) devices.

U10 Address Decoder

//`define idle
//`define state1
//`define state2
//`define state3
®
// FOR eZ80 Development Platform Rev B
// This PAL generates 4 memory chip selects
module l92_decod(
nCS_EX, //Enables Extension Module's Memory when Low
nFL_DIS, //when Low WEB Module Flash is disabled (nDIS_FL=0),
//when High nDIS_FL depends upon state of nmemenX
nCS0,
A7, //A23
A6, //A22
A5, //A21
A4, //A20
A3, //A19
A2, //A18
A1, //A17
A0, //A16
nCS2,
nEX_FL_DIS, //disables Flash on the expansion module, when Low
nEM_EN, //enables Development Platform LED and
//the general-purpose port.
nDIS_FL, //disables E-NET Module Flash when Low
nL_RD, //enables local data bus to be read by CPU
nmemen1,
UM012906-0103
2'b00
2'b01
2'b11
2'b10
PRELIMINARY
eZ80L92 Development Kit
User Manual
General Array Logic Equations
77