Logging Read Function - Mitsubishi Electric MELSEC iQ-R Series User Manual

Logging read function

More than 1000 points of logging data can be stored by transferring the device data to the file register of the CPU module
without stopping logging. This function reduces the takt time in a test demanding high-speed conversion.
Overview of the logging read function
After logging starts, an interrupt request is sent to the CPU module and an interrupt program is executed every time the preset
number of data to be read is logged.
A temperature input module has 16 points of the interrupt factor (SI) to correspond to the logging reading of each channel.
For the setting of interrupt pointers, refer to the following.
Setting interrupt pointers
Assign the interrupt factors (SI) of a temperature input module and interrupt pointers of the CPU module using the interrupt
pointer setting of the engineering tool.
The interrupt function must be set when the logging read function is used.
Starting the logging read function
To use the logging read function, set Enable (0) to 'CH1 Loading interrupt enable/disable setting' (Un\G544) and set a number
of logging points to generate an interrupt in 'CH1 Logging read points setting value' (Un\G545). This function starts when
'Operating condition setting request' (Y9) is turned on and off.
■The number of logging read points
Set a value whose integral multiple is 1000 in 'CH1 Logging read points setting value' (Un\G545). The setting range is from 1
to 1000. When a value whose integral multiple is not 1000 is set, the number of the actual logging read points is forced to
become a maximum value whose integral multiple is 1000 within the set value. The value of the number of logging read points
is stored in 'CH1 Logging read points monitor value' (Un\G440).
A value of CH1 Logging read points setting value
100
90
110
650
400
Data checking method
■Current logging read pointer
• The head pointer read from CH1 Logging data (Un\G10000 to Un\G10999) with the interrupt processing is stored in 'CH1
Current logging read pointer' (Un\G438).
• The default value of 'CH1 Current logging read pointer' (Un\G438) is -1.
• Every time the same number of data as the value stored in CH1 Logging read points monitor value (Un\G440) is logged, a
value calculated by the following formula is stored in 'CH1 Current logging read pointer' (Un\G438).
CH1 Current logging read pointer = CH1 Latest pointer - CH1 Logging read points monitor value + 1
■Previous logging read pointer
• 'CH1 Current logging read pointer' (Un\G438) at the timing when the previous read pointer detection interrupt occurs is
stored in 'CH1 Previous logging read pointer' (Un\G439).
• The default value of 'CH1 Previous logging read pointer' (Un\G439) is -1.
• 'CH1 Previous logging read pointer' (Un\G439) is used to detect the overlap of the logging read pointer detection interrupt
processing.
A value of CH1 Logging read points monitor value
100
50
100
500
250
1 FUNCTIONS
53
1.10 Logging Function
1