Neil:
this is what I would do.
instead of using 84 and ltc1298  use pic16c(71)or 711

setup reference voltage ( external  connect  to  +6 v )
when analog input voltage =  4  your ADC adres register = 0x40 (64) I think
when analog input voltage = 6  your ADC adres register = 0xFF (255)
you can use XOR or SUB even bit test instructions to determine start and end

I also have that little board with real time clock and ADC chip on it
the thing is why use 2 chips if you can use just one. you can still use
the same board  without ADC chip.
a few weeks ago I have done a project with pressure sensors which is
similar to what you are trying to do except when the pressure reaches to
50 PSI turns the timer on.Total sensors I had 6 I used 2 ( 71 )


Andre Abelian



Undetermined origin c/o LISTSERV administrator wrote:

> I have a need for measuring voltages between 4 & 6V DC. Does anyone have
> any pointers so I can get started. The reason behind this is to measure
> voltage and temperature inside my PC. I've been having trouble with
> voltages on my PC and would like to shutdown the system when things get
> way out of line.
>
> The 16F84 will communicate with the PC via RS232, it will use a DS1802
> and an LTC1298 ADC. The ADC is already on a Micromint PICSTICK I have.
>
> Thanks
>
> --
> Neil Cherry     http://home.att.net/~ncherry    ncherry@worldnet.att.net



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