4 write lock (write-protect) function, Write lock (write-protect) function -5 – Yokogawa FVX110 User Manual
Page 68
<9. In-Process Operation>
9-5
IM 01S01C01-01EN
9.4 Write lock (Write-protect)
function
The FVX110 is provided with a write lock (write-
protect) function to restrict write operations to
blocks and prevent inadvertent writing of parameter
data. To enable this function, use the write lock
switch (Hard W Lock) or the WRITE_LOCK (index
1034) (Soft W Lock).
The CPU assembly of the FVX110 is provided with
a write lock switch (switch 2 in Figure 9.5). Setting
switch 2 to On activates the write lock function, to
prevent changes to block parameters of WRITE_
LOCK_LEVEL (index 1064). Table 9.4 shows how
WRITE_LOCK_LEVEL relates to the block targeted
by write lock. In the factory default setting, WRITE_
LOCK_LEVEL is “2” (preventing writing to the LCD
transducer block, resource block and function
block). To enable the switch lock function, set "Hard
W Lock” (bit 4) of FEATURE_SEL (index 1018) to
“1” (On). (The factory default for “Hard W Lock” (bit
4) is “0” (Off).
Table 9.4
Relationship between WRITE_LOCK_
LEVEL and block targeted by write lock
WRITE_LOCK_
LEVEL
Block targeted by Write lock
0
All parameters for the LCD
transducer block and FEATURE_
SEL and WRITE_LOCK_
LEVEL parameter settings for
FEATURE_SEL
1
All parameters for the LCD
transducer block and resource
block
2
(Factory default)
All function block parameters
in addition to WRITE_LOCK_
LEVEL “1”
3
MIB and VCR in addition to
WRITE_LOCK_LEVEL “2”
When the write lock switch is disabled, set 2
(enabled) for WRITE_LOCK (index 1034) of the
resource block to enable the write lock function. To
enable the write lock function using the WRITE_
LOCK setting, FEATURE_SEL (index 1018) of
the resource block must be returned to its factory
default. (In the factory default setting, “Hard W
Lock” (bit 4) is “0” (Off and “Soft W Lock” (bit 3) is
“1” (On).
Table 9.5
FEATURE_SEL, write lock switch and
WRITE_LOCK parameter relationship
FEATURE_SEL
Write
lock
switch
WRITE_LOCK
Hard
W
Lock
(bit4)
Soft
W
Lock
(bit3)
0
(OFF)
0
(OFF)
Disabled
Unavailable
(“1” (Write lock
disabled)
1 (ON)
1 (Write lock disabled)
(Factory default)
2 (Write lock enabled)
1 (ON) 0
(OFF)
Enabled
Unavailable
(depends on write lock
switch)
* When “Hard W Lock” and “Soft W Lock” are both 1 (On), the
“Hard W Lock” setting takes precedence and “Soft W Lock” is
automatically set to 0 (Off).
1
2
O
N
O
N
"OFF" during operation
WRITE LOCK
Amplifier Assembly
F0905.ai
Figure 9.5
WRITE_LOCK Switch