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16 bit SPI problem

Started by deepak July 22, 2003
Hi fellows,

I am interfacing an adc manufactured by TI with MSP 430F139.The ADC 
uses SCLK from MSP to tranmit 16 bits of  A to D .data serially.
   MSP has an 8bit spi buffer so the SCLK will stop after exchanging 
8 bit until its started again.The slight delay in between in the SCLK 
exceeds the tolerable jitter limit.
   Could someone help as how to supply continuous clock from MSP.

There is one more fundamental doubt about devices that Use SPI as an 
interface: is the SCLK to be supplied continuously or only when data 
needs to be exchanged,because all data sheets show a coontinuous SCLK 
extending to infinity..?
 
Plz help
regards
deepak
 


Beginning Microcontrollers with the MSP430



>From: "deepak"
<kuldeepakasha@kuld...>
>Reply-To: msp430@msp4...
>To: msp430@msp4...
>Subject: [msp430] 16 bit SPI problem
>Date: Tue, 22 Jul 2003 15:17:15 -0000
>
>Hi fellows,
>
>I am interfacing an adc manufactured by TI with MSP 430F139.The ADC
>uses SCLK from MSP to tranmit 16 bits of  A to D .data serially.
>    MSP has an 8bit spi buffer so the SCLK will stop after exchanging
>8 bit until its started again.The slight delay in between in the SCLK
>exceeds the tolerable jitter limit.
>    Could someone help as how to supply continuous clock from MSP.
>
>There is one more fundamental doubt about devices that Use SPI as an
>interface: is the SCLK to be supplied continuously or only when data
>needs to be exchanged,because all data sheets show a coontinuous SCLK
>extending to infinity..?


It shouldn't need it. I've implemented 8-bit SPI in software, with the clock 
disabled when it isn't needed.

Leon
--
Leon Heller, G1HSM Tel: +44 1424 423947
Email:leon_heller@leon...
My web page: http://webspace.webring.com/people/jl/leon_heller/

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