Parameter Settings; Performance Values - Mitsubishi Electric MELSEC iQ-F Series Manual

Precautions
• Only the Value string whose uType (type of Value), s32Key (Key string), and uDepth (depth of hierarchy) completely match
those specified in pb_st30Member (member list) is acquired. Partially matched strings are not acquired.
• Special characters including escape sequences are not supported. A Value string including any special character may not
be acquired correctly. The JSON string supports 0x00 and 0x20 to 0x7E.
• "true", "false", and "null" are identified only by their first character. For numerical values, e, +, -, and the position and
number of periods are not checked.
• When the target Value string has 64 characters or more, 63 characters from the beginning are stored.
• If the target Value string is not found or is an object (pb_st30Member.uType (type of Value in member list) is K1), NULL is
stored in s64Value (Value string) of pb_st30Member (member list).
• Even if uType (type of Value) of pb_st30Member (member list) is K1 (Object), configure the settings for s32Key (Key string)
and uDepth (depth of hierarchy) of pb_st30Member (member list) because of influence on search results of this FB.
• Set pb_st30Member (member list) according to the JSON string sequence. Otherwise, the Value string may not be
acquired correctly.
• Store a NULL-terminated ASC string in the Key string.
• Any string with the multidimensional array or nested array is not acquired.
• Any independent JSON string (array, string, numerical value, true, false, null) constructed only with the following strings is
not supported.
Input type
Array alone
String alone
Numerical value alone
Boolean value alone
Null alone

Parameter settings

Parameter settings are not required for this FB.

Performance values

Module
FX5S CPU module
FX5UJ CPU module
FX5U/FX5UC CPU
*1*2
module
*1 When the program capacity is set to 128K steps, the processing speed may become slow.
*2 The standard area is used for labels.
3 DETAILS OF FB LIBRARIES
14
3.1 M+StrProcessing_JSONDeserialize_F (Acquisition of JSON String)
Example
[1, "a"]
"ab"
2
true
null
Measurement condition
Number of Number of
members characters in
JSON string
1 100
15 1000
30 16383
1 100
15 1000
30 16383
1 100
15 1000
30 16383
Processing time Maximum scan time
837.000ms 21.800ms
1670.000ms 24.500ms
64100.000ms 70.500ms
708.000ms 18.400ms
1440.000ms 21.200ms
59900.000ms 64.500ms
586.000ms 15.200ms
1190.000ms 17.900ms
50800.000ms 55.400ms
Number of scans
37 scans
97 scans
1123 scans
37 scans
97 scans
1123 scans
37 scans
97 scans
1123 scans