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Explain input output control word format of 8255. Write control word of 8255 to initialize Port A as input port, Port B and C as output port, Group A and B in Mode 0.
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written 5.5 years ago by |
To do 8-bit data transfer using the Ports A, B or C, 8255 needs to be in the IO mode. The bit pattern for the control word in the IO mode is as follows:
Calculation of CWR to initialize Port A as input port, Port B and C as output port, Group A and B in Mode 0.
CWR = (90H)