Author Topic: Write Memory  (Read 10837 times)

PLY

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Write Memory
« on: July 16, 2002, 06:28:18 AM »
HI ! I want to write memory in arear at not clear if power OFF.Then ON power the old data not clear.
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »

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Re: Write Memory
« Reply #1 on: July 16, 2002, 08:46:33 AM »
Do you mean you want to write to the non-volatile memory? You can use the SAVE_EEP command to save the data to EEPROM memory. These will not be lost after power off. When power on, read the data back using the LOAD_EEP command. There are 1700 words (16-bit) available in the M-series PLC which can be used to store non-volatile data. Note that reading and writing to EEPROM are slow and there is a fixed life cycle (about 100,000 erase/write cycles) so you should exercise necessary caution when using the EEPROM memory.
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »
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whenry

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Re: Write Memory
« Reply #2 on: July 15, 2003, 12:09:34 PM »
What constitutes a write cycle.  

1.   If I save 8 pieces of data to 8 memory locations locations using one custom function, does that constitute 8 write cycles.  

2.  Everytime A new or updated program is loaded into the PLC is that just one write cycle, or are the number of program words counted?

« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »

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Re: Write Memory
« Reply #3 on: July 15, 2003, 12:36:57 PM »
Write cycles is per memory location. So if you write 8 data to 8 different locations, each location only undergoes 1 write cycle.

When you transfer program to the PLC, each complete transfer is considered 1 cycle.

Anyway, the program EEPROM and data EEPROM occupies different memory locations so they are independent of each other.
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »
Email: support@triplc.com
Tel: 1-877-TRI-PLCS