Hi;
George was right about the information related to printer connection and consequently calculator slowing down in program execution speed.
It is clearly stated at the Printer's Manual that the system [HP41 plus printer] will interact with each other thus causing a reduction in speed, mostly in program running. The initial post in thread is not related to this particular issue, but I disagreed with George's comments; I was wrong and George was right. Makes perfect sence, the MODE key is built in the printer's panel, and at any moment, the user may switch the printer to NORM or TRACE, and the running program (or any other operation prformed by the user) must scan for this possibility OR wait for a "wait" from the printer if it is printing something.
The printer connector is, in fact, the interface itself, and at the moment it is connected to the HP41, it's resources become part of the existing function set in a different way (same as happens with the HPIL module): you plug it on any available port and their functions are always listed first in CAT 2 (except in the HP41CX's Time Fcn 1x and CX Time 2x, always the first ones in this model). If I remember well, these modules have their functions mapped in predefined positions in memory.
George, my apologies; you were right.
Cheers.