单片机毕业设计外文翻译单片机AT89C51(2)

单片机毕业论文的外文翻译

八路智能抢答器的设计

Pin Configurations

Pin Description

VCC：Supply voltage.

GND：Ground.

Port 0：Port 0 is an 8-bit open-drain bi-directional I/O port. As anoutput port, each pin can sink eight TTL inputs. When 1sare written to port 0 pins, the pins can be used as highimpedanceinputs.

Port 0 may also be configured to be the multiplexed loworderaddress/data bus during accesses to external programand data memory. In this mode P0 has internalpullups.

Port 0 also receives the code bytes during Flash programming,and outputs the code bytes during programverification. External pullups are required during program verification.

Port 1：Port 1 is an 8-bit bi-directional I/O port with internal pullups.The Port 1 output buffers can sink/source four TTL inputs.When 1s are written to Port 1 pins they are pulled high bythe internal pullups and can be used as inputs. As inputs,Port 1 pins that are externally

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