Reading and Writing integers to EEPROM

[ionize]

In the attached program, I've got most issues sorted, today, however, I found out that I didn't account for reading and writing numbers (which are minutes) up to 1440 to the EEPROM. Researching how to do it has left me confused (easy to do these days). The examples I have looked at are: http://www.matrixtsl.com/mmforums/viewt ... 26&t=15107 and http://www.matrixtsl.com/mmforums/viewt ... 26&t=11343. For starters, I'm Not sure how breaking the number into high byte and low byte is done when it can be changing up or down.
Please show me how to do it.
Many thanks to everyone for all the previous hints and helps.

Scott

[medelec35]

Hi Scott,
Have you read this thread?

I'm Not sure how breaking the number into high byte and low byte is done when it can be changing up or down.

Breaking up can be done just before the saving to EEPROM & combining can be so as soon as both addresses containing High and low bytes are retrieved.

Martin

[ionize]

Thanks Martin,
I'm trying to wrap my head around it.
Scott

[medelec35]

Hi Scott,
Your welcome.
If you give it a go, then post flowchart, I will take a look at it for you.
I can also get it working then repost (if not already working).

Martin

[ionize]

I think I added the code right but now the display is blanked or displays garbage from the start. Haven't had that problem before no matter how bad my code was. The rest of the program works as before. It works, I think, in simulation where the display can be seen but you cannot see whats in the EEPROM anymore like you could in V5. I know its the code corrupting because if I take it out, the OLED works fine. I can't see where the conflicts are.
Thanks,
Scott

[medelec35]

Hi Scott,

but you cannot see whats in the EEPROM anymore like you could in V5.

You can, you just select View menu then Console.
There will be an eeprom tab:

EEPROM Contents.png

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As for your flowchart:
You are using a discussion branch (If OX_Ontime > 255) before reading from EEPROM.
You will need to read from EEPROM first.
The way I would do it is:

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Read highbyte from EEPROM

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Read Lowbyte from EEPROM

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If highbyte = 255 && Lowbyte = 255

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Yes:  OX_Ontime = 0

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No: OX_Ontime = ByteLow+(ByteHigh << 8) 

This is because if EEPROM has not been used all the default values are 255
I would use shift 8 places (<<8) rather than *256 as its more efficient.
I would also suggest the you select the eeprom component on the dashboard, right select properties, then remove all contents from 'Initial Values'.

[ionize]

I should have known EEPROM was improved just like everything else.
I believe I added your suggestions correctly and now it simulates well but won't compile: I get: error: invalid pragma DATA argument 'MX_UINT16'
when trying to write to the chip. Since the chart simulates, I don't have a clue on where this is or what it is. Any ideas, fixes, laughter?
Thanks,
Scott

[medelec35]

Hi Scott,

won't compile: I get: error: invalid pragma DATA argument 'MX_UINT16'

That will be caused by an invalid entry in the

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Initial Values 

of the EEPROM properties.
Just click on the initial values entry box and make sure all data have been removed.
It looks like something is left within the box but it's invisible:

EEPROM1.png

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As you can see I have highlighted it.

Any ideas, fixes, laughter?

No laughter as something like like is very difficult to spot!

Another thing is you can't palace EEPROM, PWM or components with delays (including delays that would be used within a components) within interrupts.
If you do then you will get a stack corruption warning.
If ignored and the hardware appears to work, than at some point the hardware will fail.

Martin

[ionize]

Well, I think I can put this baby to bed! It's working well now, thank you so much Martin. Your direction and advice as always, spot on.
All Hail THE PROFESSOR!
Scott

[medelec35]

Thanks Scott,
I'm glad you are happy with the way it's all working.
Also thanks for the compliment, although there are people on these forums who are more like a professor than I am.