module chipsel
title 'RAMCS/CS8019AS/BAS-BA(0-3)'
U1 device 'P16V8R';

clk   pin 1;
bas   pin 2;
a9,a10,a11,a12,a13,a14,a15   pin 3,4,5,6,7,8,9;
ba0,ba1,ba2,ba3   pin 19,18,17,16;
cs8019,ramlcs,ramhcs   pin 15,14,13;
bcs   pin 12;
oe   pin 11;

H,L,C,Z,X=1,0,.C.,.Z.,.X.;
ba=[ba3,ba2,ba1,ba0];
adr=[a15,a14,a13,a12,a11,a10,a9];

equations
	ramlcs=a15;
	ramhcs=a15&a14&a13&a12&a11&a10&a9#!a15;
	cs8019=!(a15&a14&a13&a12&a11&a10&a9);
	
	ba3:=bcs&ba2#!bcs&ba3;
	ba2:=bcs&ba1#!bcs&ba2;
	ba1:=bcs&ba0#!bcs&ba1;
	ba0:=bcs&bas#!bcs&ba0;
	
	"oe=0;
test_vectors
	(adr->[ramlcs,ramhcs,cs8019])
	^h7F->[1,1,0];
	^h0F->[0,1,1];
	^h40->[1,0,1];
test_vectors
	([clk,bcs,bas]->ba)
	[C,0,1]->[X,X,X,X];
	[C,1,0]->[X,X,X,0];
	[C,1,1]->[X,X,0,1];
	[C,1,0]->[X,0,1,0];
	[C,1,1]->^b0101;
	[C,1,1]->^b1011;
	[C,1,0]->^b0110;
	[C,1,0]->^b1100;
	[C,1,1]->^b1001;
	[C,0,0]->^b1001;
	[C,0,1]->^b1001;
end chipsel;