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[SOLVED] interfacing 18F46k22 with i/o expander mcp23s17

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deeplearns

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Hi Guys
I am trying to interface 18F46k22 with 2 MCP23S17 .I am using MIKROC compiler .
I was able to cummunicate with one of them using the in built io-expander and spi library .But the problem arises when i use two i/o expander only one of them works.
Thus i tried to write a function on my own for the same .as i assumed they may require two different CS line .I was again able to do well with one expander at a time but not both .
I gave VCC to Reset pin when using my code .

My qestion is can a single CS line be used with multiple I/O expanders ?

Can i use MIKROC inbuilt library for two I/O expander ?
 

deeplearns

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well i found out that 2 i/o expanders would require 2 separate cs lines ..the address decoder functionality wont help.. may be i am doing some thing wromng .
 

Jestin_cubetech

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unused Address lines must be connected to 10K pullup resistor
 

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