power management

[adumas]

Hi... I have a picaxe 28x1 circuit that captures temperature readings and displays it on a 4-digit display via a max 7219 chip.

I would like to only display the information only periodically, e.g., every minute or so.

Can I use the sleep command in such a way that the LED is powered only when the picaxe chip "comes to life"...

Presently I have the Max chip sharing the same power rails as the picaxe chip.

Hope this message is clear...

 

[LizzieB]

The datasheet http://www.maxim-ic.com.cn/pdfserv/en/ds/MAX7219-MAX7221.pdf is your friend. If you read it you will see that the 7219 has a shutdown mode in which it uses just 150 microamps, so all you have to do is send it the shutdown code before you put the picaxe to sleep, and send it a normal mode code to wake it up when the picaxe wakes up.

 

[adumas]

That's it... I missed the info on the sheet... I was thinking the answer was more on the picaxe side...

It works wonderfully now... Thanks for your reply.