Mitsubishi L Series User Manual page 197

(40)CH Head pointer (Un\G1090 to Un\G1093)
The buffer memory address where the oldest data is stored can be checked in CH
Un\G44999). The difference between the buffer memory address where the oldest data is stored and the start
address in CH Logging data (Un\G5000 to Un\G44999) is stored.
When the value of CH2 Head pointer (Un\G1091) is 8551
Ex.
● The value in CH Head pointer (Un\G1090 to Un\G1093) is fixed to 0 since the oldest data is stored in the start address
of CH Logging data (Un\G5000 to Un\G44999) while the data of first 10000 points is logged from the logging is stated.
After the 10001st data, the place of CH
● When CH Logging hold request (Un\G1008 to Un\G1011) is turned ON (1) → OFF (0), CH
to Un\G1093) is cleared to zero.
(41)CH Latest pointer (Un\G1098 to Un\G1101)
The buffer memory address where the latest data is stored can be checked in CH
Un\G44999). The difference between the buffer memory address where the latest data is stored and the start
address in CH Logging data (Un\G5000 to Un\G44999) is stored.
When the value of CH2 Latest pointer (Un\G1099) is 8550
Ex.
Oldest data
● CH
Latest pointer (Un\G1098 to Un\G1101) increases one by one each time data is stored from the logging starts.
● When CH Logging hold request (Un\G1008 to Un\G1011) is turned ON (1) → OFF (0), CH
to Un\G1101) is cleared to zero.
CH2 Logging data
Un\G15000
Latest data Un\G23550
Un\G23551
Un\G24999
Latest pointer (Un\G1090 to Un\G1093) increases one by one.
CH2 Logging data
Un\G15000
Un\G23550
Un\G23551
Un\G24999
Logging data (Un\G5000 to
Oldest data
23551 = 15000 + 8551
Head pointer (Un\G1090
Logging data (Un\G5000 to
Latest data
23550 = 15000 + 8550
Latest pointer (Un\G1098
APPENDICES
A
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