--- nand.py-
+++ nand.py
@@ -388,6 +388,53 @@
 			new_pin_conn(self, self.dec_d, 0, n1, 'out', direc='from_in_obj')
 			new_pin_conn(self, self.dec_u, n1, n1, 'out', direc='from_in_obj')
 
+class ROM_D1(Obj):
+	def __init__(self, parent, abit_n, dlst=(), name='rom_d1', latency=10):
+		Obj.__init__(self, parent, name)
+		self.dbgout(dlst)
+		self.n = abit_n
+		for i in range(abit_n):
+			Pin( self, name_i('A', i), 'L' )
+		n1 = abit_n - 1
+		msb = getattr( self, name_i('A', n1) )
+		msb.conn = DECODER(self, 1, 'deco', latency).inp_0
+
+		if abit_n == 1:
+			dlst_v = lambda i: dlst[i] if i < len(dlst) else -1
+			dlst_b = lambda i: bool( dlst_v(i) & 1 )
+			Pin(self, 'p0', dlst_b(0) ).conn = AND(self, 'and_d', latency).inp_a
+			Pin(self, 'p1', dlst_b(1) ).conn = AND(self, 'and_u', latency).inp_a
+		
+			en_d = self.and_d.inp_b
+			en_u = self.and_u.inp_b
+			out_d = self.and_d.out
+			out_u = self.and_u.out
+		else:
+			half = 1 << n1
+			ROM_D1(self, n1, dlst[ :half ], 'rom_d', latency)
+			ROM_D1(self, n1, dlst[ half: ], 'rom_u', latency)
+			Joint_N(self, n1, 'jt_n')
+			self.jt_n.new_pin_conn(self.rom_d, 'A')
+			self.jt_n.new_pin_conn(self.rom_u, 'A')
+			self.jt_n.new_pin_conn(self, 'A', n1, direc='from_targ')
+
+			en_d = self.rom_d.en
+			en_u = self.rom_u.en
+			out_d = self.rom_d.D_0
+			out_u = self.rom_u.D_0
+
+		self.deco.out_0.conn = en_d
+		self.deco.out_1.conn = en_u
+
+		OR(self, 'or_', latency).out.conn = AND(self, 'and_out', latency).inp_a
+		out_d.conn = self.or_.inp_a
+		out_u.conn = self.or_.inp_b
+
+		Pin(self, 'en', 'L').conn = Joint(self, 'jt').new_pin()
+		self.jt.new_pin().conn = self.deco.en
+		self.jt.new_pin().conn = self.and_out.inp_b
+		self.and_out.out.conn = Pin(self, 'D_0', 'L')
+
 class CLK(Obj):
 	def __init__(self, parent, hz=1.0, name='clk', pos=(0,0), lamp_name=None):
 		Obj.__init__(self, parent, name, None, pos)