Help with a ADC0834
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I have an ADC0834 4 channel ADC that I want to use to monitor 4 different
temperature probes. After looking through the data sheets, I still don't
understand how the different channels are selected. Has anyone worked with one
of these or know how this is done?
Hank
temperature probes. After looking through the data sheets, I still don't
understand how the different channels are selected. Has anyone worked with one
of these or know how this is done?
Hank
Comments
The channel selection is made with the DI pin on the 0834. The
addressing tables in the National data sheet show the bit
combinations for the channel selection. The timing tables show
how the bits are transmitted.
Four wires are needed for the stamp connection: DI, DO, CS,
and CLK. The code for a BS2 looks something like this
' adc_chan is %1100, %1101, %1110, or %1111 for channels
' 0 through 3 in single-ended mode
' first select the channel
shiftout di_pin, clk_pin, msbfirst, [noparse][[/noparse]adc_chan]
' then read the data
shiftin do_pin, clk_pin, msbpost, [noparse][[/noparse]data\8]
Marylou
_______________________________________
--- In basicstamps@y..., "rcvehicles" <rcvehicles@y...> wrote:
> I have an ADC0834 4 channel ADC that I want to use to monitor 4
different temperature probes. After looking through the data sheets, I
still don't understand how the different channels are selected. Has
anyone worked with one of these or know how this is done?
>
> Hank
Hank
Original Message
From: "zonie999" <apstumpf@u...>
To: <basicstamps@yahoogroups.com>
Sent: Friday, January 11, 2002 1:16 AM
Subject: [noparse][[/noparse]basicstamps] Re: Help with a ADC0834
> Hank,
>
> The channel selection is made with the DI pin on the 0834. The
> addressing tables in the National data sheet show the bit
> combinations for the channel selection. The timing tables show
> how the bits are transmitted.
>
> Four wires are needed for the stamp connection: DI, DO, CS,
> and CLK. The code for a BS2 looks something like this
>
> ' adc_chan is %1100, %1101, %1110, or %1111 for channels
> ' 0 through 3 in single-ended mode
> ' first select the channel
> shiftout di_pin, clk_pin, msbfirst, [noparse][[/noparse]adc_chan]
> ' then read the data
> shiftin do_pin, clk_pin, msbpost, [noparse][[/noparse]data\8]
>
> Marylou
I forgot to mention that the 0834 chip must be enabled with with the
CS pin.
low cs_pin
shiftout di_pin, clk_pin, msbfirst, [noparse][[/noparse]adc_chan]
shiftin do_pin, clk_pin, msbpost, [noparse][[/noparse]data\8]
high cs_pin
Marylou
______________________________________
--- In basicstamps@y..., "rcvehicles" <rcvehicles@y...> wrote:
> Thanks Marylou, I'll give that a try.
>
> Hank
>
>
>
Original Message
> From: "zonie999" <apstumpf@u...>
> To: <basicstamps@y...>
> Sent: Friday, January 11, 2002 1:16 AM
> Subject: [noparse][[/noparse]basicstamps] Re: Help with a ADC0834
>
>
> > Hank,
> >
> > The channel selection is made with the DI pin on the 0834. The
> > addressing tables in the National data sheet show the bit
> > combinations for the channel selection. The timing tables show
> > how the bits are transmitted.
> >
> > Four wires are needed for the stamp connection: DI, DO, CS,
> > and CLK. The code for a BS2 looks something like this
> >
> > ' adc_chan is %1100, %1101, %1110, or %1111 for channels
> > ' 0 through 3 in single-ended mode
> > ' first select the channel
> > shiftout di_pin, clk_pin, msbfirst, [noparse][[/noparse]adc_chan]
> > ' then read the data
> > shiftin do_pin, clk_pin, msbpost, [noparse][[/noparse]data\8]
> >
> > Marylou