I am designing a battery powered device that needs to access a large EPROM ,  an
 LCD,  4 switches, and
an RTC.
Due to few IO lines I need to have discrete logic that lets me set the address
 lines on the EEPROM
serially and lets me read the data serially.
I have looked at using two '164s and 1 '165 respectively.  Is there a lower
 power way to do this?
I know I can reduce the power drain substantially on the EPROM by toggling its
 Chip Enable line only
when I need it.
(Microchip 27C256)

I am thinking about hooking up the four switches to B4-B7 and letting the
 interrupt pull us out of
SLEEP mode.  (I will also use a WDT so that we can give the update to the LCD
 often enough.)

I have been thinking about hooking the switches to ground and using the internal
 pull-ups.  However, I
know that this increases power consumption.  Does anyone know how much?  Any
 ideas on a better way to
do this?

I will be using a PIC 16F84.  Am I better off running it at a higher frequency
 and running less or at a
slower frequency running more?

I am not concerned about the RTC (1202) because it is pretty low power and the
 RST line on it takes
care of your power management.

For the LCD, I am connecting to a HD4470 part.  I am concerned about the high
 current drain that this
has.  Does anybody know anything I can do to reduce its power consumption when
 it doesn't need to
display anything?  Does turning off the Display (with that command) help?

I have never done a device before where power was important.  (Normally I just
 use a walwart. ;-) )
What is a good low-power way to condition the battery power?

What type of battery power would people recommend?  (4 or 5 C batteries?)

If anyone has any other advice (or good web sites to point me to) about power
 conservation, then I
would appreciate it.


Thanks,

Alan G. Smith

+---------------------------------------------------------
| Alan G. Smith
| ags@poboxes.com
| http://www.innovatus.com/ags