MICROPROCESSOR 8255
ARCHITECTURE OF 8085
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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BSR mode
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Mode 0 of I/O mode
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Mode 1 of I/O mode
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Mode 2 of I/O mode
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Detailed explanation-1: -Explanation: In mode 0, any port can be used as input or output and output ports are latched.
Detailed explanation-2: -8255 PPI in Mode-0 In mode 0 each group can be used as input or output. Port A, port B and port C can be used as input or output. Port C has the specialty that it can be divided in to two nibbles upper and lower. Both upper and lower can now be programmed to use as input or output.
Detailed explanation-3: -There are two basic operational modes of 8255: Bit Set/Reset mode (BSR mode). Input/Output mode (I/O mode).
Detailed explanation-4: -The port C upper and port C lower can be used in combination as an 8-bit port C. Both the port C are assigned the same address. Thus one may have either three 8-bit I/O ports or two 8-bit and two 4-bit ports from 8255. All of these ports can function independently either as input or as output ports.