diff --git a/sunspec/core/modbus/client.py b/sunspec/core/modbus/client.py
index c05bdf2..9f01134 100755
--- a/sunspec/core/modbus/client.py
+++ b/sunspec/core/modbus/client.py
@@ -26,6 +26,7 @@
 import struct
 import serial
 import sys
+import time
 
 try:
     import xml.etree.ElementTree as ET
@@ -34,6 +35,10 @@
 
 import sunspec.core.modbus.mbmap as mbmap
 
+
+deadtime_clock = getattr(time, 'monotonic', time.clock)
+
+
 PARITY_NONE = 'N'
 PARITY_EVEN = 'E'
 
@@ -56,6 +61,16 @@ class ModbusClientTimeout(ModbusClientError):
 class ModbusClientException(ModbusClientError):
     pass
 
+
+def wait_until(target, clock):
+    while True:
+        remaining = target - clock()
+        if remaining > 0:
+            time.sleep(remaining)
+        else:
+            break
+
+
 def modbus_rtu_client(name=None, baudrate=None, parity=None):
 
     global modbus_rtu_clients
@@ -148,6 +163,8 @@ def __init__(self, name='/dev/ttyUSB0', baudrate=9600, parity=None):
         self.timeout = .5
         self.write_timeout = .5
         self.devices = {}
+        self.deadtime = 44 / int(self.baudrate)
+        self.last_receive_completion = -self.deadtime
 
         self.open()
 
@@ -235,32 +252,40 @@ def _read(self, slave_id, addr, count, op=FUNC_READ_HOLDING, trace_func=None):
                 s += '%02X' % (ord(c))
             trace_func(s)
 
+        wait_until(
+            target=self.last_receive_completion + self.deadtime,
+            clock=deadtime_clock,
+        )
+
         self.serial.flushInput()
         try:
             self.serial.write(req)
         except Exception as e:
             raise ModbusClientError('Serial write error: %s' % str(e))
 
-        while len_remaining > 0:
-            c = self.serial.read(len_remaining)
-            if type(c) == bytes and sys.version_info > (3,):
-                temp = ""
-                for i in c:
-                    temp += chr(i)
-                c = temp
+        try:
+            while len_remaining > 0:
+                c = self.serial.read(len_remaining)
+                if type(c) == bytes and sys.version_info > (3,):
+                    temp = ""
+                    for i in c:
+                        temp += chr(i)
+                    c = temp
 
-            len_read = len(c);
-            if len_read > 0:
-                resp += c
-                len_remaining -= len_read
-                if len_found is False and len(resp) >= 5:
-                    if not (ord(resp[1]) & 0x80):
-                        len_remaining = (ord(resp[2]) + 5) - len(resp)
-                        len_found = True
-                    else:
-                        except_code = ord(resp[2])
-            else:
-                raise ModbusClientTimeout('Response timeout')
+                len_read = len(c);
+                if len_read > 0:
+                    resp += c
+                    len_remaining -= len_read
+                    if len_found is False and len(resp) >= 5:
+                        if not (ord(resp[1]) & 0x80):
+                            len_remaining = (ord(resp[2]) + 5) - len(resp)
+                            len_found = True
+                        else:
+                            except_code = ord(resp[2])
+                else:
+                    raise ModbusClientTimeout('Response timeout')
+        finally:
+            self.last_receive_completion = deadtime_clock()
 
         if trace_func:
             s = '%s:%s[addr=%s] <--' % (self.name, str(slave_id), addr)
@@ -354,6 +379,11 @@ def _write(self, slave_id, addr, data, trace_func=None):
                 s += '%02X' % (ord(c))
             trace_func(s)
 
+        wait_until(
+            target=self.last_receive_completion + self.deadtime,
+            clock=deadtime_clock,
+        )
+
         self.serial.flushInput()
         try:
             if sys.version_info > (3,):
@@ -362,25 +392,28 @@ def _write(self, slave_id, addr, data, trace_func=None):
         except Exception as e:
             raise ModbusClientError('Serial write error: %s' % str(e))
 
-        while len_remaining > 0:
-            c = self.serial.read(len_remaining)
-            if type(c) == bytes and sys.version_info > (3,):
-                temp = ""
-                for i in c:
-                    temp += chr(i)
-                c = temp
-            len_read = len(c);
-            if len_read > 0:
-                resp += c
-                len_remaining -= len_read
-                if len_found is False and len(resp) >= 5:
-                    if not (ord(resp[1]) & 0x80):
-                        len_remaining = 8 - len(resp)
-                        len_found = True
-                    else:
-                        except_code = ord(resp[2])
-            else:
-                raise ModbusClientTimeout('Response timeout')
+        try:
+            while len_remaining > 0:
+                c = self.serial.read(len_remaining)
+                if type(c) == bytes and sys.version_info > (3,):
+                    temp = ""
+                    for i in c:
+                        temp += chr(i)
+                    c = temp
+                len_read = len(c);
+                if len_read > 0:
+                    resp += c
+                    len_remaining -= len_read
+                    if len_found is False and len(resp) >= 5:
+                        if not (ord(resp[1]) & 0x80):
+                            len_remaining = 8 - len(resp)
+                            len_found = True
+                        else:
+                            except_code = ord(resp[2])
+                else:
+                    raise ModbusClientTimeout('Response timeout')
+        finally:
+            self.last_receive_completion = deadtime_clock()
 
         if trace_func:
             s = '%s:%s[addr=%s] <--' % (self.name, str(slave_id), addr)