Skip to content

2: Getting Started

This is a brief guide to your first few minutes on the Commander X16. For a complete New User experience, please refer to the Commander X16 User Guide.

Finding and starting programs

When starting your Commander X16, you'll notice that it's not like other computers. There is no GUI, and command line commands like DIR or LS don't get you anywhere. Here are some quick tips to getting started:

The Commander X16 uses a full screen interface known as "Editor". This was unique when it was introduced on the PET in 1977, when most computers still treated the screen as if it was a teletype display. The full screen Editor lets you use the arrow keys to move around the screen and edit or re-enter input from previous interactions.

The first thing you will want to do is view a list of files on your SD card. Type the below command and press the Return key (or Enter key) to see a list of files:

DOS

DOS "$"

You can also type @$ and press Return. All of the commands you type must be followed by the Return or Enter key, to actually execute the command.

Let's try some variations on this command:

DOS "$=D" lists just the subdirectories in the current directory.

To get the DOS command a little faster, try pressing F8, then typing $=D. You can even leave off the last quote; DOS doesn't care.

So now that you have a list of directories, try mnoving to one:

DOS "CD:BASIC"

Press F7 or type DOS"$ again to list the files in this directory. A file with .PRG at the end is a "Program" file and can be loaded with the LOAD command. The shortcut for LOAD" is the F3 key. Try it now:

LOAD

LOAD "MAD.PRG"

You can see that the program list loaded by typing LIST and pressing Enter.

RUN

Now type RUN and Enter. This will start the loaded program.

STOP

STOP isn't a command: it's a key. Press it to stop the running program.

If you are using the official Commander X16 keyboard, the key is labeled RUN STOP and is up near the upper right corner of the keyboard.

If you are using a PC keyboard, it's probably labeled Pause or Pause Brk.

Holding Control and pressing C (also written as Control+C or ^C) will also stop the running program.

There are a few ways to get back to the text screen, but the quickest is to hold Control, Alt, and press the Del key. (Or just press the RESET button.)

Using The Keyboard

The Commander X16's keyboard is a little different than a standard PC: there are three distinct modes of operation, and the keyboard can create graphic symbols known as PETSCII characters. There are also some special keys used for controlling the computer.

PETSCII Characters

When the system first boots up, the X16 will be in PETSCII Upper Case/Graphic mode. Pressing a letter key without the shift key will generate an upper case letter. Unlike a PC or Mac, this mode does not have any lower case text, so everything you type is UPPER CASE.

Now, notice the extra symbols on your keycaps? There are two sets of extra symbols: the ones on the lower-right can be accessed by holding SHIFT and a letter. Go ahead: try pressing Shift and S. You should see a small heart symbol on your screen. We know you'll love the Commander X16 as much as we do. Press Alt and a letter, and you'll get the symmbol on the lower-left corner of the screen. Try pressing Alt and the ` key next to the nummber 1. You should get a large + symbol. One of the Plusses of PETSCII is using these line drawing symbols to draw shapes on the screen.

You can also change colors by pressing Control and a number. Go ahead: Press Control+1 and type a few letters. Notice they come out in black. Now try Alt+1. Notice the cursor changes to orange, and notice the next thing you type comes out orange.

You can also use Control+9 to turn on Reverse Print and Control+0 to turn it off.

There are some unexpected changes to the PC keyboard layout, as follows:

  • The Grave key (`) prints a left arrow (←) symbol.
  • Shift+Grave prints the Pi symbol (π). This is actually the constant "pi". Try it by typing PRINT π and RETURN.
  • Shift+6 prints an up arrow (↑)
  • The \ key prints the British Pound (£).
  • The pipe (|) is replaced with a triangle corner symbol.
  • { and } are replaced with two box drawing symbols.
  • Underline (Shift+-) is replaced with a | symbol.

Note that programming languages that need {, }, and _ will alter the character set to show those symbols on the appropriate keys when needed. Or you can use ISO mode when editing C code in EDIT.

Lower Case Mode

WORKING IN PETSCII MIGHT MAKE PEOPLE THINK YOU'RE YELLING ALL THE TIME. Fortunately, there's an upper/lower case mode, too: Hold the Alt key and tap Shift to activate lower case. Notice that the upper case letters shift to lower case, and the shifted graphic symbols (such as the heart) shift to upper case letters. The tradeoff of upper/lower case mode is that half of the graphic symbols are unavailable, but you you get lower case letters.

Now try typing a command. print "Hello World" and press RETURN. Notice that you need to type print in lower case. If you did it right, you should see "Hello World" appear on the next line.

Now tap Alt+Shift again. The text will change to |ELLO oORLD. Again, this is the tradeoff: you can have the Shifted graphic symbols or lower case, but not both.

ISO Mode

Finally, the computer has ISO mode. The ISO mode character set operates more like a PC, with upper case text, lower case text, and an assortment of accented and other letters. In addition, ISO mode has the \, ~, {, and } symbols, which are not available in PETSCII modes. ISO mode is useful when you need PC compatibility or want the letters with accents. Elsewhere in this guide, we have a full manual on using the Right Alt key to compose accented symbols, like é or ō. Getting back to PETSCII mode from ISO mode is a little more complicated. Press Control+Alt+RESTORE (or Control+Alt+PrintScreen) to warm start BASIC and switch back to PETSCII mode.

EDIT text modes

The built-in EDIT utility includes a character set mode switch: Press Control+E to cycle through Upper/Graphic, Upper/Lower, and ISO mode.

Special Keys

RUN STOP

This key actually has two separate functions: "RUN" and "STOP". Holding Shift+RUN will load the first program on your SD card and automatically run it. If you are using the SD card that came with your Commander X16, this will print some information on getting started with your computer.

If you are running a BASIC program, pressing STOP will stop the program.

RESTORE

As mentioned above, RESTORE can be used with Control+Alt to perform a warm start of BASIC. Less drastic than a cold boot, this stops a running program and returns you to the READY. prompt. If you had a BASIC program loaded, you can still re-start it with RUN or view it with LIST.

Control+Alt_Delete

Yes, the Commander X16 has the famous "3 fingered salute." This performs a cold boot of the computer, including a full power cycle. You will be returned to the boot screen, and if you have an AUTOEXEC.X16, it will execute on startup.

40/80 DISPLAY

This switches the computer between 80x60 text mode and 40x30 text mode. 40x30 is more useful on CRT screens, so you may want to boot up into 40x30 mode. You can set these modes with BASIC by typing

SCREEN 1 or SCREEN 3.

Protip: you can force your computer to start in 40-column mode by modifying your AUTOBOOT.X16 file:

LOAD "AUTOBOOT.X16"
0 SCREEN 3
SAVE "@:AUTOBOOT.X16"
BOOT

Don't worry, if you don't like this change, you can change it back:

LOAD "AUTOBOOT.X16"
SCREEN 1
SAVE "@:AUTOBOOT.X16"
BOOT

F-KEYS

The F-keys, also known as the "Function Keys" are pre-loaded with special shortcuts:

F1 LIST Displays your currently loaded BASIC program.

F2 SAVE"@: is a quick shortcut for saving a program. The @: allows you to overwrite an existing file with the same name.

F3 LOAD " helps you load a program. Protip: if you use @$ to get a directory listing, you can then use the arrow keys to move up to a line with a filename. Press F3 and press RETURN to load a file.

F4 and RETURN swaps between 40 and 80 column screen modes.

F5 RUN runs the currently loaded program

F6 MONITOR Runs the machine monitor. The monitor allows you to directly edit memory, view assembly language dumps, and even write short assembly language programs at your keyboard.

F7 DOS"$ Lists the current directory

F8 DOS" allows you to enter a disk command, such as CD:. More info can be found in chapter 13.

WHAT IS PC RA RO AC XR YR SP NV#BDIZC?

There are times when the computer will drop to the MONITOR prompt. That looks like this:

C*
   PC  RA RO AC XR YR SP NV#BDIZC
.;E3BB 01 04 00 65 2B F6 ........
.█

This is the MONITOR screen. You can get there in BASIC by typing MON.

Type X and Enter to exit back to BASIC. If you just get bounced to MONITOR again, then you'll need to Control+Alt+Restore or Control+Alt+Delete to restore to a working state.

MONITOR is covered in Chapter 7.