The CANA-232/CANA-485 are a family of...


The CANA-232/CANA-485 are a family of...
A T7 CAN network consists of a host computer (PC, PLC or microcontroller), a single CANA-232/CANA-485 adapter, cables and T7 inclinometers. Power to each T7 is supplied over the network cable. T7s are connected together as a daisy chain with or without stubs. The CAN adapter can be placed anywhere along the length of the daisy chain. The last T7 device on the daisy chain needs a “terminating” cable which has a built in termination resistor (see “Related Products & Accessories” at the bottom of this page). The CAN adapter has a built in termination resistor that can be jumpered in or out using JP1. Typically, the CAN adapter is at one end of the network, so the jumper should be added to include the termination resistor. If the CAN adapter is placed in the middle of the daisy chain, the jumper should be removed (no termination resistor). In this case a “terminating” cable must be used for the T7s at both ends of the daisy chain. See the sample diagrams below:


The CANA-232/CANA-485 are a family of adapter boards/modules that allow a host PC, PLC or microcontroller to communicate with a network of up to 64 US Digital T7 inclinometers. The CAN adapter is only needed to communicate with the USD-CAN interface version of the T7. The RS232 version of the T7 can connect to a RS232 port without an adapter.
The CAN adapter serves as a command translator between a host serial port and the USD-CAN bus used by the T7 network. RS-232 or RS-485 can be used on the host side, depending on the type of adapter used. The adapter frees the user from a complicated network interface on the host side. A host can access every T7 on the network by sending/receiving simple serial port commands to/from the CAN adapter. The underlying serial commands used by both adapter boards are identical. For example, to read the angle from a particular T7, the host simply sends a serial command to the CANA-232/CANA-485 adapter which contains the command type and the address of the destination T7. The CAN adapter board translates the serial port commands from the host to the USD-CAN protocol and handles all network functions (access, error correction, etc) to access an T7 on the network. Conversely, the CAN adapter also translates the reply data from the T7 and sends the data back to the host on the serial bus. As a result, the CAN adapter makes it very easy for a user to read/write data to network of T7s.
The host side serial interface used by the CAN Adapter is fully documented so that users can write their own serial port command software. A set of simple functions are provided in the included Windows DLL that allow users to read and write data to a network of T7s. A Windows demo application is also included that can display the angles and temperature, as well as setting operating modes, orientation, zero position, damping / averaging time, direction, and more for every T7 on the network.