Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) System, I/O and Communications Functions - Manual (Page 199)

Logic Functions - Book 1
REMOTE DIGITAL OUTPUT MODULE BLOCK (RDOM)
6-21
6.4 REMOTE DIGITAL OUTPUT MODULE BLOCK (RDOM)
The remote digital output module blocks serve as the data handling blocks for the remote
digital output modules. Each block can output as many as 16 discrete values to a remote
digital output module. The RDOM block is valid for use with the following remote modules:
Module No. Type Description
ICSO O8 R1 Output 8 relay output channels 2A
ICSO O8 Y1 Output 8 transistor output channels 24VDC 2A
ICSK 20 F1 Input/Output 12 non-isolated 24VDC input channels and 8 isolated relay
output channels
ICSC 08 L1 Input/Output 8 user-configurable channels for 24VDC input or 24VDC
500mA transistor output
The RDOM block provides its outputs to the CS-31 bus via a Remote I/O Interface (RIO)
Module installed in the instrument. The instrument database must have one RDOM block for
each remote digital output module on the CS-31 bus. The RDOM can be connected using the
RIO block MODOUT to this blocks MODIN connection.
Block outputs are the data, data quality, and active and unacknowledged status of the block’s
diagnostic error. A functional block diagram of a RDOM block is shown in Figure 6-8. The
displays, which are used to configure this block, are shown in Figures 6-9, 6-10, and 6-11.
6.4.1 Remote Digital Output Module Block Operation
The RDOM blocks are data repositories for the instrument. All remote digital output values
are buffered in one of five possible task state tables. Process input and output routines use
these tables to pass data between the module blocks which run at the 50ms base scan rate
and the process algorithm blocks which run at the configured scan group interval. All valid
remote output values are written to the interface module during each 50ms base scan cycle.
The interface module then distributes the values to the bus connected remote digital output
modules.
Remote digital output module blocks generate a diagnostic error based upon an
unsuppressed I/O mismatch condition or remote module error. Events are reported for
switching the block mode to auto or manual, and for the diagnostic errors.
During a warm start condition, a pre-run read is performed to determine if the module is
performing a power restart. If power is restarted, the result is sent to the module, result quality
is marked bad and track status is set to track. If power is not restarted, the result is initialized
to the previous value, result quality is marked good, and track status is set to track.
During a cold or frozen start condition, the result is set depending on the configuration of the
Restart Output attribute (False, True, or Previous) where previous indicates the previous
database value.