ABB AC500-S Safety User Manual page 309

Table 87: FB name: SF_FLASH_READ
Name Data type
VAR_INPUT
EN BOOL
NB WORD
SEG BYTE
BNR WORD
SM DWORD
VAR_OUTPUT
2020/06/19
NOTICE!
Access to the flash memory is only possible using the function blocks
SF_FLASH_WRITE, SF_FLASH_DEL and SF_FLASH_READ.
NB blocks are read starting at block BNR within segment SEG and stored
starting at address SM.
32 binary data or 16 word data or 8 double word data are read per block.
One block contains 38 bytes:
– 32 bytes of data
– 4 bytes for CRC checksum
– 1 byte as "written" identifier
– 1 byte for alignment
Ä Table 88 "Structure of one of the flash memory segments with user data"
on page 310
Reading a data set is triggered once by a FALSE/TRUE edge at input EN. If no
error occurred while reading the data, output DONE is set to TRUE and the out-
puts ERR and ERNO are set to FALSE. The data set is stored beginning at the
defined start flag SM.
Storing the data set can take several CPU cycles.
If an error occurs during reading, DONE and ERR are set to TRUE and data
from SM are equal to 0. The error type is indicated at output ERNO.
Initial value
FALSE
16#0000
16#00
16#0000
16#00000000
3ADR025091M0208, 12, en_US
AC500-S libraries > SafetyExt_AC500_V22.lib
Description, parameter values
Activation of the FB using a positive edge
The following applies:
● EN = FALSE/TRUE edge: Reading the data set is
carried out once.
● EN = TRUE: The function block is not processed,
i.e. it does not change its outputs anymore.
Number of data set blocks (decimal 1 ... 1724)
Input NB is used to specify the number of blocks con-
tained in the data set. 32 byte data or 16 word data
or 8 double word data are read per block.
Valid values: 1 ... 1724
Example:
● SM = ADR(%MW0.0) and NB = 1: Data are
stored at %MW0.0 to %MW0.15 (1 block = 16
word data)
● SM = ADR(%MW0.0) and NB = 2: Data are
stored at %MW0.0 to %MW0.31 (2 blocks = 32
word data)
ID number of the data segment (16#01 or 16#02)
Starting block number in the flash memory data seg-
ment (decimal 0 ... 1723)
Destination address for the read data set (address of
the first variable where the data are placed)
Configuration and programming
309