diff --git a/pymlac/Ptp.py b/pymlac/Ptp.py
deleted file mode 100644
index fb67f7f..0000000
--- a/pymlac/Ptp.py
+++ /dev/null
@@ -1,94 +0,0 @@
-#!/usr/bin/python
-
-"""
-Emulate the Paper Tape Punch (PTP).
-"""
-
-
-from Globals import *
-
-
-class Ptp(object):
-
-    # define various internal states
-    MOTOR_ON = 1
-    MOTOR_OFF = 0
-    DEVICE_NOT_READY = 0
-    DEVICE_READY = 1
-    PTP_CHARS_PER_SECOND = 30
-    DEVICE_NOT_READY_CYCLES = int(CYCLES_PER_SECOND / PTP_CHARS_PER_SECOND)
-
-    # module-level state variables
-    motor_state = MOTOR_OFF
-    device_state = DEVICE_NOT_READY
-    filename = None
-    open_file = None
-    cycle_count = None
-
-
-    def init(self):
-        """Initialize the punch."""
-
-        self.motor_state = self.MOTOR_OFF
-        self.device_state = self.DEVICE_NOT_READY
-        self.filename = None
-        self.open_file = None
-
-    def mount(self, ptp_filename):
-        """Mount a file on the punch."""
-
-        self.motor_state = self.MOTOR_OFF
-        self.device_state = self.DEVICE_NOT_READY
-        self.filename = ptp_filename
-        self.open_file = open(self.filename, 'w')
-
-    def dismount(self):
-        """Dismount the file from the punch."""
-
-        self.motor_state = self.MOTOR_OFF
-        self.device_state = self.DEVICE_NOT_READY
-        if self.open_file:
-            self.open_file.close()
-        self.filename = None
-        self.open_file = None
-
-    def start(self):
-        """Start the punch motor."""
-
-        self.motor_state = self.MOTOR_ON
-        self.device_state = self.DEVICE_NOT_READY
-        self.cycle_count = self.DEVICE_NOT_READY_CYCLES
-
-    def stop(self):
-        """Stop the punch motor."""
-
-        self.motor_state = self.MOTOR_OFF
-        self.device_state = self.DEVICE_NOT_READY
-
-    def write(self, ch):
-        """Punch an 8 bit value to the tape file."""
-
-        print('PTP.write: ch=%s (%d)' % (type(ch), ch))
-
-        self.device_state = self.DEVICE_NOT_READY
-        self.cycle_count = self.DEVICE_NOT_READY_CYCLES
-        self.open_file.write(str(ch))
-
-    def tick(self, cycles):
-        """Move the state of the punch along."""
-
-        print('PTP: tick() called, cycles=%s, self.cycle_count=%s' % (str(cycles), str(self.cycle_count)))
-
-        if self.motor_state == self.MOTOR_OFF or not self.open_file:
-            self.device_state = self.DEVICE_NOT_READY
-            return
-
-        self.cycle_count -= cycles
-        if self.cycle_count <= 0:
-            self.device_state = self.DEVICE_READY
-
-    def ready(self):
-        """Get the punch state."""
-
-        return self.device_state == self.DEVICE_READY
-
diff --git a/pymlac/Ptr.py b/pymlac/Ptr.py
deleted file mode 100644
index 656b5e9..0000000
--- a/pymlac/Ptr.py
+++ /dev/null
@@ -1,124 +0,0 @@
-#!/usr/bin/python
-
-"""
-Emulate the imlac Paper Tape Reader (PTR).
-
-We take some pains to closely emulate the *real* PTR device, even
-including misuse, such as no tape mounted.  This means we must tell
-the PTR object how many CPU cycles have passed (tick()).
-"""
-
-from Globals import *
-
-
-class Ptr(object):
-
-    # number of chars per second we want
-    CharsPerSecond = 300
-
-    # duty cycle for PTR is 30% ready and 70% not ready
-    ReadyCycles = int((CYCLES_PER_SECOND / CharsPerSecond) / 0.7) / 25
-    NotReadyCycles = int((CYCLES_PER_SECOND / CharsPerSecond) / 0.3) / 25
-
-    # no tape in reader, return 0377 (all holes see light)
-    PtrEOF = 0377
-
-    # module-level state variables
-    motor_on = False
-    device_ready = False
-    open_file = None
-    filename = None
-    at_eof = True
-    value = PtrEOF
-    cycle_count = 0
-
-
-    def __init__(self):
-        """Initialize the paertape reader device."""
-
-        self.motor_on = False
-        self.device_ready = False
-        self.open_file = None
-        self.filename = None
-        self.at_eof = True
-        self.value = self.PtrEOF
-        self.cycle_count = 0
-
-    def mount(self, fname):
-        """Mount papertape file on the reader device."""
-
-        self.motor_on = False
-        self.device_ready = False
-        self.cycle_count = self.NotReadyCycles
-        self.filename = fname
-        self.open_file = open(self.filename, 'rb')
-        self.at_eof = False
-        self.value = None
-
-    def dismount(self):
-        """Dismount a papertape file."""
-
-        self.motor_on = False
-        self.device_ready = False
-        if self.filename:
-            self.open_file.close()
-            self.open_file = None
-        self.filename = None
-        self.at_eof = True
-        self.value = self.PtrEOF
-
-    def start(self):
-        """Turn papertape reader motor on."""
-
-        self.motor_on = True
-        self.device_ready = False
-        self.cycle_count = self.ReadyCycles
-
-    def stop(self):
-        """Stop reader motor."""
-
-        self.motor_on = False
-        self.device_ready = False
-        self.cycle_count = self.ReadyCycles
-
-    def read(self):
-        """Read papertape value."""
-
-        return self.value
-
-    def eof(self):
-        """Return reader EOF status."""
-
-        return self.at_eof
-
-    def tick(self, cycles):
-        """Called to push PTR state along.
-
-        cycles  number of cycles passed since last tick
-        """
-
-        # if end of tape or motor off, do nothing, state remains unchanged
-        if self.at_eof or not self.motor_on:
-            return
-
-        self.cycle_count -= cycles
-        if self.cycle_count <= 0:
-            if self.device_ready:
-                self.device_ready = False
-                self.cycle_count += self.NotReadyCycles
-            else:
-                self.device_ready = True
-                self.cycle_count += self.ReadyCycles
-                self.value = self.open_file.read(1)
-                if len(self.value) < 1:
-                    # EOF on input file, pretend end of tape
-                    self.at_eof = True
-                    self.value = self.PtrEOF
-                else:
-                    self.value = ord(self.value)
-
-    def ready(self):
-        """Test if reader is ready."""
-
-        return self.device_ready
-