OPTO 22 BD-DEVNET, Руководство пользователя

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DEVICENET INFORMATION
BD-DEVNET User’s Guide 3-1
DEVICENET INFORMATION
DEVICENET INFORMATION
DATA ACCESS
DeviceNet reads and writes access the adapter data buffers. The buffers are open
collector inverting drivers with inverting input bus transceivers providing data read
capability. For a bit to act as an input, the corresponding output data buffer bit must have
a zero written to it. This causes the open collector driver to be turned OFF, and the
physical I/O bit will be pulled high by a pull-up resistor. External signals may then pull the
input signal to ground, which will be read as a logic 1.
No status information is available for either the inputs or outputs.
The I/O drivers are fully compatible with Opto 22 I/O modules.
DEVICENET MODEL
The BD-DEVNET (16-bit Opto 22 Digital Adapter) device operates as a slave on the DeviceNet
network. The unit supports Explicit Messages and Polled I/O Messages of the predefined
master/slave connection set. It does not support the Explicit Unconnected Message Manager
(UCMM).