Odd BREAK key problem

[Dr Memory]

I tried to find an answer to this, as there are many keyboard issue threads, but was unable to.  If this has already been solved, please direct me to the correct thread, or at least something resembling the title of said thread.

 

I have an 800XL whose BREAK key works in programs, such as the REV. A version of SUPER SALT.  It also works in BASIC, in the sense that it makes a new line happen and aborts the current line.

 

It does not work in the built-in self-test.  What the heck?  How can that even be?

 

I tried swapping the 4051s and cleaning the ribbon connector but neither had any effect.  And honestly, this was already a very clean connector.  It's a Type 5 keyboard and seems to be in really good condition except for this problem.

 

I found several threads where people had the opposite problem, where only BREAK worked, but none where BREAK worked in user programs but not in the internal self test program.

 

This is the same machine with U1MB installed, but that seems to be working great, and I couldn't find any menu items that said anything like "make BREAK key act funny". 

 

 

[mimo]

It's a feature of the self test. It does not show as working

[Dr Memory]

Ah, so it's not actually broken?  Thank you!

 

I would not have guessed that, and am not sure how I never noticed that before, but here we are.

[TGB1718]

 

9 minutes ago, mimo said:

It's a feature of the self test. It does not show as working

May have something to do with the fact that the BREAK key generates an interrupt which could be disabled for the keyboard test