Verison 1.0.3 Release

Based on Buildbotics 0.4.14

src/py/bbctrl/I2C.py

@@ -0,0 +1,91 @@
+################################################################################
+#                                                                              #
+#                This file is part of the Buildbotics firmware.                #
+#                                                                              #
+#                  Copyright (c) 2015 - 2018, Buildbotics LLC                  #
+#                             All rights reserved.                             #
+#                                                                              #
+#     This file ("the software") is free software: you can redistribute it     #
+#     and/or modify it under the terms of the GNU General Public License,      #
+#      version 2 as published by the Free Software Foundation. You should      #
+#      have received a copy of the GNU General Public License, version 2       #
+#     along with the software. If not, see <http://www.gnu.org/licenses/>.     #
+#                                                                              #
+#     The software is distributed in the hope that it will be useful, but      #
+#          WITHOUT ANY WARRANTY; without even the implied warranty of          #
+#      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU       #
+#               Lesser General Public License for more details.                #
+#                                                                              #
+#       You should have received a copy of the GNU Lesser General Public       #
+#                License along with the software.  If not, see                 #
+#                       <http://www.gnu.org/licenses/>.                        #
+#                                                                              #
+#                For information regarding this software email:                #
+#                  "Joseph Coffland" <joseph@buildbotics.com>                  #
+#                                                                              #
+################################################################################
+
+import errno
+
+try:
+    try:
+        import smbus
+    except:
+        import smbus2 as smbus
+except:
+    smbus = None
+
+
+class I2C(object):
+    def __init__(self, port, disabled):
+        self.port = port
+        self.i2c_bus = None
+        self.disabled = disabled or smbus is None
+
+
+    def connect(self):
+        if self.disabled: return
+        if self.i2c_bus is None:
+            try:
+                self.i2c_bus = smbus.SMBus(self.port)
+
+            except OSError as e:
+                self.i2c_bus = None
+                if e.errno == errno.ENOENT: self.disabled = True
+                else: raise type(e)('I2C failed to open device: %s' % e)
+
+
+    def read_word(self, addr):
+        self.connect()
+        if self.disabled: return
+
+        try:
+            return self.i2c_bus.read_word_data(addr, 0)
+
+        except IOError as e:
+            self.i2c_bus.close()
+            self.i2c_bus = None
+            raise type(e)('I2C read word failed: %s' % e)
+
+
+    def write(self, addr, cmd, byte = None, word = None, block = None):
+        self.connect()
+        if self.disabled: return
+
+        try:
+            if byte is not None:
+                self.i2c_bus.write_byte_data(addr, cmd, byte)
+
+            elif word is not None:
+                self.i2c_bus.write_word_data(addr, cmd, word)
+
+            elif block is not None:
+                if isinstance(block, str): block = list(map(ord, block))
+                self.i2c_bus.write_i2c_block_data(addr, cmd, block)
+
+            else: self.i2c_bus.write_byte(addr, cmd)
+
+        except IOError as e:
+            self.i2c_bus.close()
+            self.i2c_bus = None
+            raise type(e)('I2C write failed: %s' % e)