74181 ALU design on Altera MAX II CPLD

74181 is 4-bit arithmetic and logic unit introduced by Texas Instruments in March 1970 and it is known for being the first ALU in a single package. This chip is no longer in manufacturing but still, it is quite popular in CA (computer architecture) courses in many colleges.

To test the behavior of this 4-bit ALU we decided to construct it on Altera MAX II CPLD. For this project, we choose EPM240T100C5 CPLD and logic design is implemented using Altera Quartus II. For logic design, we refer to Fairchild Semiconductor’s DM74LS181 datasheet. This setup is tested on basic EPM240 series development board with some mechanical switches and couple of LEDs.

74181 4-bit ALU test setup with the EPM240T100C5 development board.

There are several test circuits available for 74181 ALU and our test setup is partially based on Electronics for Your (EFY) 1997 article. In another test setup, we use HEF4040 to drive, A and B operands of this ALU.

The test setup attached to this article is the minimum configuration which anyone can build with a small number of commonly available electronic components.

All the downloadable content related to this project are available at google drive.

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