Hi All,

For “fun”, I implemented initial versions of both the 0x2b interrupt hook and a 
partial 0x2d implementation to locate the Logger device driver. 

The 0x2d version is very bare bones and does not include several functions 
required to be “fully compliant”. It only responds to the install check 
function for whichever multiplexer it allocates. Other function requests only 
respond with AL=0x00 which i guess is “not implemented”. 

As such, 0x2d uses 35 bytes more resident memory than 0x2b. (actually 49 bytes 
more if you count a “title” string that is not required). If I spend the time 
making it fully compliant, it will require even more. It really would need 
function 04 (determine chained ints) and should have 06 (device driver info). 

I think overall, it might be better to figure out why walking the device driver 
chain was not working correctly. Most likely, it was some dumb thing I was 
doing wrong. It would have the smallest resident footprint of the locating 

I’ll probably take another look at that. Or maybe, I’ll just stick with the 
0x2d multiplexer despite it’s larger footprint. 

All are better (and much faster) than the temporary brute force search in 
previous versions.



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