Re: Confused about CPU-external.cmp

Posted by throwinshapes on
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/Confused-about-CPU-external-cmp-tp4032166p4037220.html

Should I be concerned if my implementation of CPU is passing CPU.tst, but failing CPU-external.tst?

I found this blurb on the website document for project 5 while researching this issue:
"6. The projects/05 folder contains a set of files whose names include the label “external”. These
test files are no longer in use, and will be removed from future versions of the Nand to Tetris
software suite. Therefore, you should ignore them."

The current download "Download the Nand2tetris Software Suite Version 2.6" from the website still includes the -external files.


EDIT: I found later my CPU was failing during ComputerRect.tst. Diagnosing this, I found my CPU implementation was allowing load to be enabled on the D register regardless of whether the instruction was a A or D type. I guess CPU-external.tst contains a test that finds this error, while CPU.tst does not.