82c55 has three state buffer, so it can be directly linked to the data bus of the system.
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The PB port of 82c55 can be set to mode 2.
A. 对
B. 错
The extended I / O occupies the address resources of the off chip data memory.
A. 对
B. 错
Mode 1 of 82c55 is unconditional input and output mode.
A. 对
B. 错
82c55 PC port can be reset by position.
A. 对
B. 错
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