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NEW_GUY
Joined: 31 Aug 2012 Posts: 10 Location: India
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Interrupt driven SPI with multiple slaves |
Posted: Mon Sep 10, 2012 9:46 pm |
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Hello folks,
I am trying some impish things, but they really proper ways to study the protocols like SPI.
I am working with SPI which works fine with 1 slave at regular timer 0 1 msec interrupt, but when I adds the second slave then neither of them works...
I think they might have timing issues, OR the CS may not be in sync with the h/w SPI interrupt.
A little help would be good,
Thank you. |
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Gabriel
Joined: 03 Aug 2009 Posts: 1067 Location: Panama
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Posted: Tue Sep 11, 2012 12:37 pm |
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in SPI you have 4 control lines:
SDI: Common to all slaves
SDO: Common to all slaves
CLK: Common to all slaves
CS: independant for each slave
so if you have 3 slaves you will share SDI, SDO,and CLK... but your will need a SEPARATE IO for each CS line of each slave...
G. _________________ CCS PCM 5.078 & CCS PCH 5.093 |
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bkamen
Joined: 07 Jan 2004 Posts: 1615 Location: Central Illinois, USA
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Posted: Thu Sep 13, 2012 10:57 pm |
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As a comment from an onlooker, that original post is pretty incoherent.
I can't stress enough that a forum like this needs really clear explanation of terms and problems.
If we have a hard time interpreting your request/problem/question, you will most likely get the wrong answer to that request for help.
As the old saying goes, "Garbage in, garbage out".
-Ben _________________ Dazed and confused? I don't think so. Just "plain lost" will do. :D |
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