Robox Controls are equipped with retentive memory.

It is divided into three well-defined areas: user, parameters and alarm history.

The default size of the user area, which includes 2500 NVR(4 Bytes), 2500 NVRR(8 Bytes), 24 NVSR(128 Bytes) and 20480 Bytes of user structs, is 53,552 Bytes.

In case the user increases this area, such as by increasing the number of registers or the size of the retentive user structs, it automatically increases to 64,900 Bytes.

RTE at switch on generates alarm 9000 if the sum of space occupied by NVR, NVRR, NVSR and retentive user structs exceeds 64900 Bytes. The registers are reset to zero but if you return to the previous configuration, the value of the registers is restored.

RTE at switch on generates 9001 alarm if:

•The sum of the space occupied by NVR, NVRR, NVSR, and retentive user structs has been increased but without exceeding the default size of 53,552 Bytes. If you return to the previous configuration, the value of the registers is not lost. The registers however, are reset only after resetting the alarm

•The sum of the space occupied by NVR, NVRR, NVSR, and Retentive User Structs was decreased and the previous size of the same retentive memory was no larger than the default size (53,552 Bytes). Despite having configured less NVR, NVRR, NVSR and retentive user structs the area size still remains the same unless explicit DEFAULT_K_ON_PS command in override.cfg file. If you revert to the previous configuration, the value of the registers is not lost. The registers however, are reset only after resetting the alarm

RTE at switch on generates alarms 1, 9003, 3 if the sum of space occupied by NVR, NVRR, NVSR and retentive user structs has been increased exceeding the default size of 53,552 Bytes. The registers are reset to zero and the previous value lost forever (even by restoring the previous configuration).

RTE at switch on generates alarms 9005, 9002, 9004 if the sum of the space occupied by NVR, NVRR, NVSR and Retentive User Structs has been decreased and the previous size of the same retentive memory was greater than the default size (53.552 Bytes). If you return to the previous configuration, the value of the registers is not lost. The registers however, are reset only after resetting the alarm.

NOTE: From RTE 34.24.11, in case of memory loss, after resetting its alarms, memory copy is performed in /DUMP/ equivalent to that generated RQ_RETMEM_SAVE.

NOTE: Through the PFID and TSRPF keywords, it is possible to monitor the duration of the power failure signal and the time used by RTE to save the entire storage.

NOTE: Through the MREPORT command, information about the current memory allocation can be viewed.

Subdivision of retentive memory

User area

This is where the following are stored:

•NVR

•NVRR

•NVSR

•User-defined Structs RETENTIONAL

•Persistent Global Variables

Parameter Area.

For exclusive use by RTE.

Parameter registers (retentive predefined variables) are stored in it.

Alarm history area.

In it the alarm history is stored as a circular buffer.

The default size is 500.

The user can increase the buffer size (from project configurator). The number of entries is limited by RTE (with warning in the report) taking into account the limits of available retentive memory.

Example