12 thoughts on “Telit module Flash Memory PROGRAM/ERASE CYCLES per BLOCK parameter”
GM862 modules use M36W0R6040T1ZAQ Flash Memory
IT has 100,000 PROGRAM/ERASE CYCLES per BLOCK. (look attach)
Do you use same memory for GL865.
If not what type of Flash memory this module have?
The number of cycles is the same for GL865, 100K. There are several suppliers involved, for more details on this matter please make use of your direct contact to Telit.
Let me ask another question, related to this matter. Is there a way to minimise wear of the FLASH cells, by declaring certain Python variables go into RAM, instead of FLASH memory?
Of course you then lose the RAM contents in case of power loss, but in actual cases many variables with short lifetime would not suffer from this fact. Instead, one could declare the more critical values only to go to the FLASH memory space, thereby reducing overall FLASH usage.
Regards,
Tom
But Tom, aren’t all variables in RAM, or maybe you are referring to something else?
Well, good point, hopefully so. But I remember reading somewhere in Telit´s documentation, something like "do not use as a data logger" or similar. Can you explain why this warning was issued?
Tom
Yes indeed is written, but talks about the persistent data storage, for example keeping GPS tracks or monitoring values logs; depending of how fast and how much data is written, it may be or not feasible. In any case a replaceable memory will save the module and can add other benefits as well.
From Easy Script in Python:
NOTE:
It is highly recommended not to use the module as a data logger since all flash memories have limited number of writing and deleting cycles.
"for example keeping GPS tracks or monitoring values logs"
I agree, and want to abstain from doing so, knowing very well that FLASH memories have limits on write cycle endurance.
But you just earlier said that all variables are kept in RAM. So is this warning about file operations, or how do I manage which data goes to RAM and what goes to FLASH, if any variables or data at all go to FLASH, when written?
That was originally my point, how to be sure NOT to stress the FLASH memory.
Thanks, Tom
Nothing goes to flash memory unless you use file operations, runtime variables are kept in RAM.
Very good, thanks! This is now crystal clear.
Tom
Another question on this stopic. In short: it is not totally clear is it safe to use commands that stores their parameters in NVM often.
GM862 modules use M36W0R6040T1ZAQ Flash Memory
IT has 100,000 PROGRAM/ERASE CYCLES per BLOCK. (look attach)
Do you use same memory for GL865.
If not what type of Flash memory this module have?
The number of cycles is the same for GL865, 100K. There are several suppliers involved, for more details on this matter please make use of your direct contact to Telit.
Let me ask another question, related to this matter. Is there a way to minimise wear of the FLASH cells, by declaring certain Python variables go into RAM, instead of FLASH memory?
Of course you then lose the RAM contents in case of power loss, but in actual cases many variables with short lifetime would not suffer from this fact. Instead, one could declare the more critical values only to go to the FLASH memory space, thereby reducing overall FLASH usage.
Regards,
Tom
But Tom, aren’t all variables in RAM, or maybe you are referring to something else?
Well, good point, hopefully so. But I remember reading somewhere in Telit´s documentation, something like "do not use as a data logger" or similar. Can you explain why this warning was issued?
Tom
Yes indeed is written, but talks about the persistent data storage, for example keeping GPS tracks or monitoring values logs; depending of how fast and how much data is written, it may be or not feasible. In any case a replaceable memory will save the module and can add other benefits as well.
From Easy Script in Python:
"for example keeping GPS tracks or monitoring values logs"
I agree, and want to abstain from doing so, knowing very well that FLASH memories have limits on write cycle endurance.
But you just earlier said that all variables are kept in RAM. So is this warning about file operations, or how do I manage which data goes to RAM and what goes to FLASH, if any variables or data at all go to FLASH, when written?
That was originally my point, how to be sure NOT to stress the FLASH memory.
Thanks, Tom
Nothing goes to flash memory unless you use file operations, runtime variables are kept in RAM.
Very good, thanks! This is now crystal clear.
Tom
Another question on this stopic. In short: it is not totally clear is it safe to use commands that stores their parameters in NVM often.
GL868-DUAL, 10.00.186. Modem is controlled by Python script. Depending on config file script runs AT+CGCLASS, AT+SCFG, AT#SMSAT… with different parameters at startup. Modem is scheduled to reboot 4 times per day. Is this algorythm safe for module? From here http://www.telit.com/en/services/technical-forum/technical-forum.php?p_id=331&f_ac=thread&f_thread=274&suche=CME%20Error%2023 it follows that answer is "Rather yes than no" but I’m not sure.
So your module writes some values 4 times a day? You don’t have to worry for such usage.
Thank you for reply, Cosmin.