Setting the Scrolling Region on VT100's VT220's VT320's VT420's, VT510's etc.

I obviously did not check very well. Thank you for both the corrections AND especially for your results. This is the first time I have heard of DECterm supporting more than 24 lines, so the answers which you provide are particularly helpful since they confirm the results that have been found by E. Groenenberg and John Wilson, and specifically in respect of screens of more than 24 lines of which you are the only one to note what DEC did when more than 24 lines are available. The specific target in this case is the SD: for RT-11 which uses a scrolling region from line 8 to line 24. What I will do with this information poses a problem. Does anyone else use SD: under RT-11? My very first reaction: SET SD HEIGHT=nnn or SET SD LINES=nnn Which seems more user friendly? If there is any interest in having: SET SD WIDTH=nnn This option could also be implemented to use the capacity of a 132 character text line rather than always confining the output to 80 characters. SD: offers a graphics (only for a VT100) display which shows the values of all the registers and the first 4 values on the stack. THANK YOU AGAIN! Jerome Fine P.S. Comments on SET command vocabulary and any other suggestions will be very welcome and helpful, especially from anyone who still uses RT-11 and SD:.