Addresses Allocated To Slave Units - Omron CS1W-CRM21 Operation Manual

Exchanging Data with the CPU Unit
Remote I/O Communications Operation When a Communications Error Occurs
Communications Error Input Data Zero Clear Mode
5-1-4

Addresses Allocated to Slave Units

If ESTP (Communications Error Communications Stop Mode) is turned ON on
the DIP switch on the front of the Master Unit, all remote I/O communications
will stop when an communications error occurs at any Slave Unit. (The Com-
munications Error Communications Stop Flag at status bit 02 also will turn
ON.) If ESTP is set to OFF, remote I/O communications continue.
When the cause of the communications error is removed, the Slave Unit is
automatically restored in the network. There is no need to restart or to cycle
the power to the Master Unit.
Input Data Zero Clear Mode can be set from the CX-Integrator for communi-
cations errors. If a communications error occurs for a Slave Unit in this mode,
all input data for that Slave Unit is cleared to zeros. If Input Data Zero Clear
Mode is not set, then the input data is held for the Slave Unit even if a commu-
nications error occurs. This can be used, for example, to suppress triggering
operations when communications errors have occurred in systems where ON
input data signals are used as triggers for operation.
• Each Slave Unit is allocated memory in the Special I/O Unit area of the
CIO Area (CIO 2000 to CIO 2959) in the CPU Unit, in order of node
address (fixed) and from the following beginning address. (See note.)
Beginning address: CIO 2000 + (10 x unit number)
(The "unit number" is the number by which the CPU Unit identifies
Special I/O Units (from 0 to 95). It is set on the rotary switch on the
front of the Master Unit.)
Note When the communications mode number is set to 8 (software set-
ting), the first address can be set to any address in the CPU Unit's
CIO, WR, HR, or DM Area). (The number of allocated nodes can
also be specified.) Even in this case, however, the node address or-
der is fixed.
• The area after the Output Area (the area allocated to Output Slave Units)
is the Input Area (the area allocated to Input Slave Units). Within each of
these areas, the allocated addresses are determined in ascending order
of node addresses.
Section 5-1
103