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Easier Header Access

A project log for Mega-One-8-One

An Educational Implementation of the Classic 74181 Arithmetic-Logic Unit

daves-dev-labDave's Dev Lab 05/17/2018 at 22:101 Comment

As noted in the earlier log entry (1+1 Does Equal 2 !!!!), having the signal pins on the edge of the board in the same location as the status LEDs made it pretty difficult to integrate the unit into other projects. I spent some time adding a new 1x22 header to the board to facilitate integration into projects. I decided to leave out the Pn and Gn signals since it is unlikely that this design will be used to chain multiple units together. I also had expected to go to 4 layers on the PCB to make this happen, however, it became very clear that the way the schematic and gates are laid out in a semi-bus structure that it was relatively easy to add the header. I don't know if this was an intentional result from the original designers or unintentional result of the designs optimizations... new files uploaded with prototype pictures to follow! stay tune for a new project using the Mega-One-8-One as the primary ALU!

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GreenMonkeyLabs wrote 05/18/2018 at 19:59 point

Very cool, Dave!

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