VCCC 2025: Bally Edition
Author: @MattPilz
Category: Wild
System: Bally Astrocade (1978)
Language: Blue RAM BASIC
Len source code: 330 Bytes
Video Demo: https://youtu.be/NDg4Heluk3A
Instructions:
(==| EMULATION INSTRUCTIONS - ASSUMES WINDOWS |==)
1. Download and extract the latest MAME binaries:
https://www.mamedev.org/release.html
2. Download the Astrocade ROM collection and copy the contents of "mame" folder to your "mame/roms" directory:
https://ballyalley.com/emulation/cart_images/ROMs/astrocade_rom_collection.zip
3. Place the XMAS2025.WAV file somewhere accessible, I recommend putting it right in the MAME root folder.
4. Launch mame from command-line:
mame.exe astrocde brb11 -exp blue_ram_16k
OPTIONAL: You can add -nofilter and -keepaspect to get a crisp pixel look. I use this longer line to launch:
mame.exe astrocde brb11 -exp blue_ram_16k -nofilter -keepaspect -window -mouse -keyboardprovider dinput
5. Perform the following key sequence (will result in ":INPUT")
KEYBOARD_. → NUMPAD_+ → NUMPAD_ENTER → KEYBOARD_2 → KEYBOARD_C
6. Press <TAB> then FILE MANAGER > Cassette and browse to XMAS2025.WAV to select.
7. Press RETURN TO PREVIOUS MENU then TAPE CONTROL then PLAY. Press TAB to return to BASIC.
8. Wait for playback to complete (can hold INSERT on keyboard to speed it up). you should see a blue background and input prompt.
(If you want to LIST the code, press the key combo: NUMPAD_ENTER → LETTER_O → LETTER_C)
9. Perform the following key sequence (will execute "RUN")
NUMPAD_ENTER → KEYPAD_PAGE_DOWN → LETTER_C
10. Watch the snowflake generate and evolve endlessly! You can hold in the INSERT key to view the design evolutions in warp speed.
11. To halt program, press KEYPAD_PAGE_DOWN.
12. Press ESC to exit MAME and return to desktop.
(==| PHYSICAL HARDWARE INSTRUCTIONS |==)
This process requires that you have a Bally Astrocade and Blue RAM BASIC expansion. It can get complicated! Basically:
1. Transfer the XMAS2025.WAV file to a physical cassette or prepare it for playback in a system that has 3.5mm audio out capabilities.
2. Power up the Bally and load Blue RAM BASIC. This will not run on Bally BASIC nor Astro BASIC.
3. With the BASIC overlay on the keypad, press the following sequence (will result in "INPUT")
BLUE_SHIFT : WORD_SHIFT INPUT GO
4. Play the audio file from the device attached to the cassette jack of the interface.
5. If successful (within 30 seconds) you should see blue background and input prompt.
6. Press the following sequence (will execute "RUN")
WORD_SHIFT RUN GO
7. Watch the snowflake generate and evolve endlessly!
8. To halt program, press HALT (RUN) key.
9. Power off Bally when done!
Description:
A long delayed successor to my 2022 and 2023 Bally wild entries. I recomment reading the 2022 companion blog article here to understand more of Bally's limitations and potential: https://mattpilz.com/bally-arcade-vintage-computing-christmas-challenge-2022-breakdown/
This is just a fun entry to be creative and still output the required shape, except I add to it in an animated way using the limited commands available in Bally. It has not been well optimized albeit 330 bytes still seems reasonable for what it achieves!
The program uses various blend mode effects of the draw state and three tones of snowflake shade (white, gray, light blue) to create a randomized glistening and evolving appearance. The results can be very interesting.
Comments:
Go Bally!
- Matt
https://YouTube.com/MattPilz
https://MattPilz.com
https://twitter.com/MattPilz