Author Topic: DM430E Persistent (non-volatile) display log  (Read 524 times)

Offline JHansonHere

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DM430E Persistent (non-volatile) display log
« on: September 27, 2023, 04:18:09 PM »
I need to have a page with a scollable log of 100 String entries that will not erase after power cycle. Non-volatile memory only stores a single integer value at a time. I think a value of U8 would be fine for each of the 100 logs. I know I could combine to get 4 values per Non-volatile memory location using a U32, but that isn't ideal.

Would 25 non-volatile memory values (U32 [4 combined U8 values]) for the 100 entries and 1 non-volatile memory value for the current head of the log be the best way to make this work for the DM430E?

Then feed the 25 values into a PLC unit that converts the values into an array in the correct order to use for the lookup table to generate the log?

Any suggestions or other ideas would be greatly appreciated. This feels like a very clunky way to build a persistent log.

Offline pinias

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Re: DM430E Persistent (non-volatile) display log
« Reply #1 on: September 28, 2023, 02:40:12 AM »
it seems what you want is to store values at the DM430,  so a non volatile memory will work- U32.

on the other hand you said the PLC will use it as a lookup table to generate the log- I do not understand this part...if I would have values stored at the display certainly my controller will look for those and use them to perform some sort of logic.

what exactly you mean by saying  "a PLC unit that converts the values into an array in the correct order to use for the lookup table to generate the log?" :o

Regards

Offline JHansonHere

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Re: DM430E Persistent (non-volatile) display log
« Reply #2 on: September 28, 2023, 08:06:45 PM »
By PLC Unit, I meant a POU with Structured text to take in the variable for the Current Head of the log, and parse in all the values to put in an array of U8 values representing each of the fails or messages for the log.

Then a second POU with the new log array as the input. Use that array to build the log for the display of the String messages/status.