Udo van den Heuvel wrote in a message to All:

 UvdH> Why 'must' (?) devicedrivers be written in 16-bit and not in
 UvdH> 32-bit code? 

Some OS/2 device drivers are 16-bit, while others are 32-bit.  It depends
upon the type of driver.  Most of the reason is historical, since OS/2 1.x
was a 16-bit system.  However, there are some advantages to having 16-bit
physical device drivers, since most physical devices have 16-bit interfaces
and you end up with smaller drivers.  You can also use 32-bit 386
instructions inside your 16-bit driver if your compiler supports this;
certainly your assembler does.
 
-- Mike


---