Toshiba 6F3B0253 user manual Operating System Overview

6F3B0253

5. Operating System Overview

Special register SW55 is used to specify the number of Data registers to be stored in the EEPROM. The allowable setting value is 0 to 2048.

The table below shows the correspondence between the SW55 value and Data registers saved in the EEPROM.

SW55 setting	Range of Data registers saved	Remarks
value	in EEPROM
0	None
1	D0000 only
2	D0000 to D0001
3	D0000 to D0002
:	:
2047	D0000 to D2046
2048	D0000 to D2047	Default value
Others	D0000 to D2047	Regarded as 2048

When the EEPROM Write command is executed, the T1-16S checks the value of SW55 and saves the Data registers into the EEPROM depending on the SW55 value. The value of SW55 itself is also saved in the EEPROM.

At the initial load or the EEPROM Read command is executed, the T1-16S checks the value for SW55 in the EEPROM and transfers the corresponding number of data to the Data registers of the RAM.

NOTE

(1)The EEPROM has the life limit for writing. It is 100,000 times. Pay attention not to exceed the limit. If the number of execution of EEPROM Write command exceeds 100,000 times, EEPROM alarm flag (S007) comes ON.

(2)Even in RUN mode, the EEPROM Write command can be executed. However, in this case, only the user program is written into the EEPROM. (D register data and setting information are not saved.)

(3)The data in the EEPROM can also be read or written by using the program instruction (FUN236 XFER instruction).

(4)When the EEPROM writing is executed by the XFER instruction in the user program, T1-16S does not update the internal EEPROM write counts. Therefore the EEPROM alarm flag (S007) will not correspond to this operation. Pay attention to the life limit of the EEPROM.

68 T1-16S User’s Manual