DeviceNet Master Protocol API

DeviceNet-Master Dual-Port Memory • 41
Slave State
The slave state field is available for master implementations only. It indicates whether the master is in
cyclic data exchange to all configured slaves. In case there is at least one slave missing or if the slave
has a diagnostic request pending, the status is set to FAILED. For protocols that support non-cyclic
communication only, the slave state is set to OK as soon as a valid configuration is found.
Status and Error Codes
Code (Symbolic Constant) Numerical Value Meaning
RCX_SLAVE_STATE_UNDEFINED 0x00000000 UNDEFINED
RCX_SLAVE_STATE_OK 0x00000001 OK
RCX_SLAVE_STATE_FAILED 0x00000002 FAILED (at least one slave)
Others are reserved
Table 21: Status and Error Codes
Slave Error Log Indicator
The error log indicator field holds the number of entries in the internal error log. If all entries are read
from the log, the field is set to zero.
Note: This function is not yet supported.
Number of Configured Slaves
The firmware maintains a list of slaves to which the master has to open a connection. This list is
derived from the configuration database created by SYCON.net (see 6.1). This field holds the number
of configured slaves.
Number of Active Slaves
The firmware maintains a list of slaves to which the master has successfully opened a connection.
Ideally, the number of active slaves is equal to the number of configured slaves. For certain Fieldbus
systems it could be possible that the slave is shown as activated, but still has a problem in terms of a
diagnostic issue. This field holds the number of active slaves.
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Edition 3 – API:DeviceNet-Master#EN– 2009/01