YASKAWA VIPA SPEED7 - SFC 14 - DPRD_DAT - Read Consistent Data

The return value contains an error code if an error is detected when the function is being
processed.
If no error did occur, then RET_VAL contains the length of the data that was transferred.
The amount of read data for a DP slave depends on the diagnostic
status.
More detailed information about general error information is to be found at the beginning
of this chapter.
The SFC 13 specific error information consists of a subset of the error information for
SFC 59 RD_REC.
More detailed information is available from the help for SFC 59.
14.1.12 SFC 14 - DPRD_DAT - Read consistent data
The SFC 14 DPRD_DAT (read consistent data of a DP norm slave) reads consistent data
from a DP norm slave. The length of the consistent data must be three or more than four
bytes, while the maximum length is 128Byte. Please refer to the manual of your specific
CPU for details. Input parameter RECORD defines the target area where the read data is
saved when the data transfer has been completed without errors. The length of the
respective target area must be the same as the length that you have configured for the
selected module.
If the module consists of a DP-norm slave of modular construction or with multiple DP-
identifiers, then a single SFC 14 call can only access the data of a single module / DP-
identifier at the configured start address.
SFC 14 is used because a load command accessing the periphery or the process image
of the inputs can read a maximum of four contiguous bytes.
Consistent data
Consistent data is data, where the contents belongs to the same category and that may
not be separated. It is, for instance, important that data returned by analog modules is
always processed consistently, i.e. the value returned by analog modules must not be
modified incorrectly when it is read at two different times.
Parameters
Parameter Declaration Data type Memory block Description
LADDR INPUT WORD I, Q, M, D, L,
constant
Configured start address of the receive data buffer
of the module from which the data must be read
RET_VAL OUTPUT INT I, Q, M, D, L The return value contains an error code if an error
is detected when the function is being processed
RECORD OUTPUT ANY I, Q, M, D, L Target area for the user data that was read. The
length must be exactly the same as the length that
was configured for the selected module. Only data
type BYTE is permitted.
RET_VAL (Return value)
Error information
Description
Definition
RET_VAL (Return value)
VIPA SPEED7
Integrated Standard
System Functions > SFC 14 - DPRD_DAT - Read consistent data
HB00 | OPL_SP7 | Operation list | en | 18-30 659