diff --git a/milkymist/asmicon/multiplexer.py b/milkymist/asmicon/multiplexer.py
index 6ab16a4dd..f3d5ffbfd 100644
--- a/milkymist/asmicon/multiplexer.py
+++ b/milkymist/asmicon/multiplexer.py
@@ -29,7 +29,7 @@ class _CommandChooser:
 		self.want_reads = Signal()
 		self.want_writes = Signal()
 		# NB: cas_n/ras_n/we_n are 1 when stb is inactive
-		self.cmd = CommandRequestRW(self.requests[0].a.bv.width, self.requests[0].ba.bv.width, tagbits)
+		self.cmd = CommandRequestRW(len(self.requests[0].a), len(self.requests[0].ba), tagbits)
 	
 	def get_fragment(self):
 		comb = []
@@ -102,7 +102,7 @@ class _Datapath:
 	def get_fragment(self):
 		comb = []
 		sync = []
-		tagbits = self.hub.tag_call.bv.width
+		tagbits = len(self.hub.tag_call)
 		
 		rd_valid = Signal()
 		rd_tag = Signal(BV(tagbits))
@@ -169,7 +169,7 @@ class Multiplexer:
 		
 		# Command choosing
 		requests = [bm.cmd for bm in self.bank_machines]
-		tagbits = self.hub.tag_call.bv.width
+		tagbits = len(self.hub.tag_call)
 		choose_cmd = _CommandChooser(requests, tagbits)
 		choose_req = _CommandChooser(requests, tagbits)
 		comb += [
diff --git a/milkymist/dfii/__init__.py b/milkymist/dfii/__init__.py
index 4bf28af75..3f6c7a0ad 100644
--- a/milkymist/dfii/__init__.py
+++ b/milkymist/dfii/__init__.py
@@ -16,11 +16,11 @@ class PhaseInjector:
 		self._command = RegisterFields("command",
 			[self._cs, self._we, self._cas, self._ras, self._wren, self._rden])
 		
-		self._address = RegisterField("address", self.phase.address.bv.width)
-		self._baddress = RegisterField("baddress", self.phase.bank.bv.width)
+		self._address = RegisterField("address", len(self.phase.address))
+		self._baddress = RegisterField("baddress", len(self.phase.bank))
 		
-		self._wrdata = RegisterField("wrdata", self.phase.wrdata.bv.width)
-		self._rddata = RegisterField("rddata", self.phase.rddata.bv.width, READ_ONLY, WRITE_ONLY)
+		self._wrdata = RegisterField("wrdata", len(self.phase.wrdata))
+		self._rddata = RegisterField("rddata", len(self.phase.rddata), READ_ONLY, WRITE_ONLY)
 	
 	def get_registers(self):
 		return [self._command,