diff --git a/python/src/trezorlib/debuglink.py b/python/src/trezorlib/debuglink.py
index df84f23b4..f9e948bf1 100644
--- a/python/src/trezorlib/debuglink.py
+++ b/python/src/trezorlib/debuglink.py
@@ -89,12 +89,20 @@ class DebugLink:
 
     def read_pin_encoded(self):
         state = self.state()
+        if state.matrix is None:
+            raise RuntimeError("PIN matrix does not exist (are you running Trezor T?)")
+        if state.pin is None:
+            raise RuntimeError("PIN is not set")
         return self.encode_pin(state.pin, state.matrix)
 
     def encode_pin(self, pin, matrix=None):
         """Transform correct PIN according to the displayed matrix."""
         if matrix is None:
             matrix = self.state().matrix
+            if matrix is None:
+                # we are on trezor-core
+                return pin
+
         return "".join([str(matrix.index(p) + 1) for p in pin])
 
     def read_recovery_word(self):
@@ -228,8 +236,11 @@ class DebugUI:
             # This will also freeze on old bridges, where Read and Write are not
             # separate operations, because it relies on ButtonAck being sent without
             # waiting for a response.
-            self.debuglink.wait_layout()
-            self.debuglink.press_yes()
+            layout = self.debuglink.wait_layout()
+            if layout.text == "PinDialog":
+                self.debuglink.input(self.get_pin())
+            else:
+                self.debuglink.press_yes()
         elif self.input_flow is self.INPUT_FLOW_DONE:
             raise AssertionError("input flow ended prematurely")
         else:
@@ -243,10 +254,10 @@ class DebugUI:
             # respond with correct pin
             return self.debuglink.read_pin_encoded()
 
-        if self.pins == []:
+        try:
+            return self.debuglink.encode_pin(next(self.pins))
+        except StopIteration:
             raise AssertionError("PIN sequence ended prematurely")
-        else:
-            return self.debuglink.encode_pin(self.pins.pop(0))
 
     def get_passphrase(self, available_on_device):
         return self.passphrase
@@ -425,10 +436,7 @@ class TrezorClientDebugLink(TrezorClient):
         """Respond to PIN prompts from device with the provided PINs.
         The sequence must be at least as long as the expected number of PIN prompts.
         """
-        # XXX This currently only works on T1 as a response to PinMatrixRequest, but
-        # if we modify trezor-core to introduce PIN prompts predictably (i.e. by
-        # a new ButtonRequestType), it could also be used on TT via debug.input()
-        self.ui.pins = list(pins)
+        self.ui.pins = iter(pins)
 
     def use_passphrase(self, passphrase):
         """Respond to passphrase prompts from device with the provided passphrase."""