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flotulopex
- 14th December 2006, 16:46
Hello,

I'm using a 16F88 and an LCD display.

Is it possible to switch OFF the LCD display during sleep mode to drop the power consumption even more?

If yes, how?
Archangel
- 14th December 2006, 17:21
Hi Roger,
sure it's possible, just power your LCD from a pic pin, you might have to use a switching transistor, and you might not. How much current does your display draw when in full display minus backlight, and how much does it draw when all blank? It may not be worth the effort, I have seen LCDs powered by very small batteries for very extended times.
JS
Acetronics2
- 14th December 2006, 17:27
Hello,


If yes, how?

Just apply Power through a Pic PIN when NOT asleep ... and think to change the pin level BEFORE entering sleep !!!

La Pallice book 34, chapter 9,10 and 11 !!!

Alain
flotulopex
- 14th December 2006, 17:49
Okay,

I should have think about such a simple solution...

"La Pallice", do you mean the Compiler's Manual?

Thank you.
Acetronics2
- 15th December 2006, 06:45
Okay,


"La Pallice", do you mean the Compiler's Manual?

Thank you.

No,Flotul ...

The man who wrote around year 1700 ... , between others: " a quarter before he died, he was still alive ..."

Alain
sougata
- 16th December 2006, 05:40
Hi,

If you are powering your LCD you need to re-initialize the LCD. PBP would do that for you when it encounters the next LCDOUT instruction. All you need to do is

FLAGS=0

This will guide PBP LCD library that the LCD has not yet been initialized.
flotulopex
- 16th December 2006, 07:35
I don't understand.


If you are powering your LCD...

Do you mean this if I power the LCD through a PIC's Pin ?

Shall I set FLAG=0 when I come back from sleep mode?
Ioannis
- 16th December 2006, 09:11
Look at page 93 of the latest manual. It is FLAGS (with S) not FLAG.

If you power down your LCD, also set FLAGS=0. Before using any LCDout commands.

Ioannis
flotulopex
- 16th December 2006, 10:23
Thank you.

I found it now too...

Didn't think this was important.
sougata
- 16th December 2006, 11:22
Hi,

I hope that it is clear now. And thanks Ioannis for marking flutoplex's mistake.
Ioannis
- 16th December 2006, 11:39
Hi Sougata,

you are welcome. A simple typo mistake can lead to many hours of wasted time. Been there before....

Ioannis