Booting PCjr In 80 Columns
I own an IBM PCjr, as do many of my coworkers. We would all like to know if there is any way to make the PCjr boot DOS 2.1 in an 80-column format instead of 40 columns. Presently, to get DOS in 80 columns, I execute the program "Rebound" which was published in COMPUTE!. I then press Fn-Break, and the DOS prompt appears in 80 columns. Can you show me a simpler way?
No tricks are needed to get 80 columns on the PCjr, since DOS has a command specifically for that purpose. Just type MODE 80 at the DOS prompt with the DOS disk in the drive. To get back to 40 columns, type MODE 40. Additional parameters let you shift the display left or right to center it on the screen. MODE 80,L shifts the display two characters to the left, and MODE 80,R shifts to the right. A third parameter, T, displays a test pattern on the screen for precise alignment. For example, MODE 80,R,T shifts the display to the right and prints the digits 0–9 eight times across the screen. Then you're asked if you can see the leftmost 0. If you can't, press N and the display shifts again followed by the same prompt. Press Y to return to the DOS prompt.
You can make the computer automatically switch to 80 columns when it's turned on by using a batch file. To create the batch file, insert one of your disks with system files on it and enter the command COPY CON AUTOEXEC.BAT. Then type MODE 80 and press the F6 function key (Fn-6) followed by Enter. When the drive stops spinning, display the directory: You should see the file AUTOEXEC.BAT. This file is automatically executed when you turn on the computer. For more information about batch files, see "All About IBM Batch Files" in the September and October 1985 issues of COMPUTE!. Since MODE is an external DOS command, you must also have the file MODE.COM on the same disk. To add this feature to all your boot disks, use the COPY command to copy both AUTOEXEC.BAT and MODE.COM to each disk.