CB34-EX Hardware Changes

Changes from H/W Rev. 1.3 to 1.5 (1.4 was used in internal development):
1.  Modified to be DeviceNet compliant
2.  Replaced discontinued Philips PCA82C251T CAN transceiver with DeviceNet-compliant TI SN65HVD252D CAN transceiver
3.  Replaced 5-pin terminal strip JP1 with DeviceNet-compatible gold-pin version
4.  Added microSD memory card slot
5.  Added external reset switch (reset via pin-hole)

Changes from H/W Rev. 1.5 to 1.6
1.  Added support for dual RS-485 configuration (in this configuration, half duplex is the only RS-485 configuration available on the DB9 connector - the TSTRIP5 connector can be configured for either half duplex or full duplex)