Lunar Lander, ASCII Graphics version

History

An ASCII Graphics version of Lunar Lander, written in BASIC. This version was originally made by Creative Computing and adapted by Corey Cohen for the Apple-1. He announced it on Applefritter in 2012.

Publications at the time were packed with Lunar Lander like BASIC games. For example, in 101 BASIC Computer Games three are listed under the name Rocket. In the same period, another BASIC collection book listed another two comparible games.

The first known use of the name Lunar Lander for a video game of this type was in the 1975 book What to Do After You Hit Return, a collection of BASIC computer games by the People's Computer Company similar to Ahl's book, which included versions named Crash and Lunar Lander.

As explained on Wikipedia.

Instructions

This version of the game is actually easier to play, as there are visuals in the form of ASCII graphics. The actual position of the Lunar Module is shown in relation with the moon surface.

The game gives the following instructions:

INSTRUCTIONS (Y OR N)?Y

YOU ARE LANDING ON THE MOON!!!
YOU ARE 1000 FEET ABOVE YOUR LANDING SPOT.

YOU HAVE DOWNWARD VELOCITY OF 50 FT/SEC.
YOU HAVE 150 UNITS OF FUEL REMAIN.

(1) AFTER EACH SECOND, HEIGHT, VELOCITY, AND FUEL WILL BE REPORTED.
(2) AT THE '?', ENTER THE NUMBER OF UNITS OF FUEL YOU WISH YO BURN DURING THE NEXT SECOND.
(3) EACH UNIT OF FUEL WILL SLOW YOUR DESCENT BY 1 FOOT/SEC.
(4) THE MAXIMUM THRUST IS 30 FEET/SEC OR 30 UNITS OF FUEL PER SECOND.
(5) THE DECENT ENGINE WILL SHUTDOWN AUTOMATICALLY ON LUNAR CONTACT.

Burn the fuel effectively to control the downward velocity of the lander. Enter a value between 0 and 30, representing the units of fuel per second to burn in this round. Landing to hard will crash the lander.

Sound effects

The game has sound output through the TO TAPE jack of the ACI. It has sound effects when the lander burns fuel and when it runs out of fuel. The following was mentioned about this by another Applefritter user named Sherlock:

I also noticed a few other things. I tried plugging in a simple set of earbud headphones into the audio-out of the ACI, and it worked great, so if anyone is looking for a really easy way of testing this out, this is a way.

Emulator fix

Because of the sound effects, this version of the game does not work properly in emulators. This can be fixed by changing the last three lines of BASIC code, follow these steps after the program is started:

1. Do a RESET
2. Return to BASIC again with E2B3R RETURN
3. Change the lines: 900 RETURN RETURN, 910 RETURN RETURN and 999 RETURN RETURN
4. Start the program again with RUN RETURN.

References

• Announcement of this game by Corey Cohen and sound tip by Sherlock on Applefritter.
• Lunar Lander genre on Wikipedia.
• 101 BASIC Computer Games (p. 182-187) lists three similar games.
• What to Do After You Hit Return (p. 104-107, 150-151) lists two comparible games.