Bally Alley Astrocast: Episode 16 - Interview with Andy Guevara of Bit Fiddlers

In episode #16 of the Bally Alley Astrocast, Kevin Bunch interviews Andy Guevara. The interview took place Saturday, May 16, 2020. Andy wrote three programs that were released on cartridge for the Bally Arcade/Astrocade. The first cartridge was Machine Language Manager (MLM), released by The Bit Fiddlers in 1982. L&M Software approached Andy due to his machine language skills and a collaboration got underway that produced Ms. Candyman and Sea Devil, which were both released on cartridge in 1983. Andy also wrote some additional software: Chicken and the Goldfish Demo were released on tape, while a few others were released as type-in programs. Mr. Guevara's used an Apple II Plus with a Z80 card which ran the CP/M operating system to write most of his software for the Bally Arcade/Astrocade.

Recurring Links 

• BallyAlley.com - Bally Arcade / Astrocade Website
• What's New at BallyAlley.com
• Bally Alley Blog
• Orphaned Computers & Game Systems Website
• Bally Alley Discussion Group
• Bally Arcade / Astrocade Atari Age Sub-forum
• Bally Arcade/Astrocade High Score Club
• Bally Alley Astrocast Facebook Page
• The Classic Gaming Bookcast - By Chris Federico

Machine Language Manager (MLM)

• Machine Language Manager (MLM) is a 2KB cartridge written by Andy Guevara in 1981 for the Bally Arcade/Astrocade. It was released by The Bit Fiddlers in late 1981/early 1982.
• There is a series of four videos about the MLM. The episodes are called, "Part 1: Overview and Background," "Part 2: How to Use the MLM," "Part 3: Using MLM Example Programs," and "Part 4: Using MLM with the Astrocade MAME Emulation."

• Machine Language Manager User's Manual - This manual explains how to program in machine language using the "MLM" cartridge. There is also plenty of information that explains how to program the Bally Arcade/Astrocade in general. The complete source code listing for the cartridge is included.
• Machine Language Manager Programs - Digitally archived Bally Arcade/Astrocade programs that will load with the Machine Language Manager cartridge and the 300-BAUD tape interface.
• Machine Language Manager - Source Code - This is the Z80 assembly source code the for MLM cartridge in ready to assemble format.

Sea Devil

• Sea Devil is a 4K third party game. It was released in 1983 by L&M Software. This cartridge was written by Andy Guevara (of The Bit Fiddlers). You are the guardian of a 21st century undersea farm. Not only is this important to the survival of the people on earth, but the company you work for have risked millions on this venture. Zardos, the evil king of a distant planet, needs this food for himself. He has sent android divers with other sea creatures to steal this food. You must destroy the hoard of poachers as quickly as possible because each bit of food (the white abalone on the bottom) they get will cost you bonus score at the end of the screen. Beware, the poachers are releasing undersea mines to destroy you, avoid them by evasive action.

• Sea Devil Manual - (1983) Game "manual" (instructions) for Sea Devil by L&M Software.
• Sea Devil Ad - (1983) Advertisement for Sea Devil. This document contains much more of the game's backstory than is in the manual.
• Sea Devil Cartridge - Picture of the Sea Devil cartridge.
• HSC01 Round 10: Sea Devil / The Pits - Sea Devil was played in the Astrocade High Score Club on AtariAge in July 2016.

Ms. Candyman

• Ms. Candyman is a 4K cartridge released by L&M Software in 1983. It was programmed by Andy Guevara. Ms. Candyman is the sequel to 1983's Candy Man, which was released on tape. This is the description of the game from an advertisement: "Real arcade action with joysticks, 1 or 2 players and 3 levels of difficulty. More than 20 screens, each faster than the one before. Full screen display in exquisite detail. Ms. Candyman must pick up all of the lifesavers as quickly as possible while avoiding contact with the Ghosts & Goblins. During the first half of a screen the Ghosts or Goblins will try to catch you. During the 2nd half of a screen the Ghosts or Goblins will take up protective positions to keep you away from the life savers. Each contact costs Ms. Candyman one life and she will nose-dive head first off the bottom of the play field. A wrecker or ambulance will carry her off."

• Candy Man is the prequel to Ms. Candyman by L&M Software. It was released on tape. It loads via the Astrovision release of Bally BASIC (usually called "AstroBASIC"). The game was written by Bill Loos and Greg Miller, who make up L&M Software. It's unclear to me how much of this game is written in BASIC, but by the speed of this game, my guess is that it relies heavily on machine language subroutines built into the Bally's 8K on-board system ROM. Andy didn't directly work on Candy Man, but the programmers of the game might have used his machine language routines in the game.

• Ms. Candyman Ad - L&M Software's very rare cartridge release for the Astrocade. This game is one of those rare occasions where the rarity of the game does not speak about the quality of gameplay. A great game.
• Ms. Candyman Review - Michael Prosise reviewed Ms. Candyman in his "The Game Player #13" column in the November 29, 1983 of the Arcadian newsletter.
• Ms. Candyman Disassembly - This is a partially commented Z80 disassembly of Ms. Candyman. All of the games graphics were found and most of the code was disassembled, but not commented. Hopefully Andy can provide the printed source code listing so that this game can be completely commented.
• Ms. Candyman High Score Club - Ms. Candyman was played for the Astrocade High Score Club in June 2017 for HSC02, Round 6: Ms. Candyman / The Mummy's Treasure.

Chicken

• Chicken! - The Bit Fiddlers, 1982. It's late... you've got to get your brood home in time to watch "Fowl Play." The only problem... there's six lanes of freeway between you and home. And every day it seems to get worse... CHICKEN! is a one or two player game of skill. It pits each player against six lanes of highway of ever increasing traffic density. The object, of course, is to get your chickens across the road.

• Chicken source code - This is Richard Degler's disassembly of the Bit Fiddler's "Chicken (The Bit Fiddlers).bin." This game originally loaded via Bally BASIC, AstroBASIC or the "Machine Language Manager." This version of the binary will run as a cartridge.

Goldfish Demo

• Goldfish Demo - Seven goldfish (actually they are neon tetras) swim around a fishtank, a clock runs, and a cat meows every minute.

• Goldfish Source Code - In January 2008, Lance F. Squire converted the Goldfish Demo to run as a cartridge.

Standard Color Generator

• Standard Color Generator - By Andy Guevara/The Bit Fiddlers. BASIC EXPRESS, THE 3, no. 2 (May/June 1981): 15-16. "Machine Language Manager" Manual (Page 7-4) This video test software generates 8 standard colors used in TV work. It is for use with the Bally Arcade/Astrocade and Bally BASIC or the Machine Language Manager. The "Standard Color Generator" program will display a series of color bars which can be used to set the colors on your TV set. The color bars are displayed from left to right in the following order: Black, White, Yellow, Green, Blue, Magenta, Red and Cyan. This video is broken into several part: Overview of Program, Program Loading and Running (Direct Capture), and Program Loading and Running (Video of TV). This program is useful to help adjust colors on a TV. It's also an excellent example of showing more than the usual two colors on the screen at once from BASIC.

The Bit Fiddler's Corner

• Andy Guevara programmed the "Machine Language Manager" ("MLM") cartridge for the Astrocade as well as writing "The Bit Fiddler's Corner" tutorials to help support the program. The tutorials complement "MLM," but they also have a general focus, so this information can be used without reinterpretation by Bally Arcade/Astrocade assembly language programmers, or those wishing to learn about the machine.
• The Bit Fiddler's Corner - Links to each article in the series as they appeared in the Arcadian.
• The Bit Fiddler's Corner - These tutorials were converted to text by Adam Trionfo on January 13, 2002. This is the complete series in one Rich Text Format document.

Andy Guevara - Miscellaneous Links

• Atari Archive - Kevin Bunch is "chronicling the early history of video games with mini-documentaries focused on a particular game or topic.
• Z-80 SoftCard - Bit Fiddler's programs were created using this Z-80 card, or one similar to it, for the Apple II Plus.
• "Astrocade Owners!" Advertisement - This half-page ad appeared in the January 1983 issue of Electronic Games. "Here's a list of professionals who support your computer with programs, hardware and information to help you enjoy your Astrocade to the maximum!" Each of the 17 companies listed in the ad has contact information, along with a brief summary of what they do. Running this ad was very expensive. Richard Houser, from Astrocade Sourcebook (one of the companies in the ad), has said that everyone in this ad grouped together funds to run it for several issues in Electronic Games magazine. When asked if the ad worked at all, Richard said that it did have noticeable results. A higher-quality version of the just the ad can be read here.

Feedback

There is no feedback covered in this episode,but we would love to hear your thoughts and comments about this (or any) Astrocast episode or about your history with the Bally Arcade/Astrocade. The best way to contact us is via email at BallyAlley or through via the Bally Alley Discussion Group at Groups.io.

Next Episode's Coverage

Astrocast #16 was supposed to be the first of a sporadic multi-part series that covers some of the material in the "AstroBASIC" manual. That episode was bumped to make room for the interview with Andy Guevara. The "AstroBASIC" manual overview will be in Astrocast #17.