History

History of Pachislot: From the First Stop Buttons to Smart Slots

Pachislot did not begin with anime screens or the machines of the 1980s. Its roots reach back to the 1960s. Since then, changes to reel control, machine standards, bonus systems and medal handling have repeatedly reshaped what players experience in Japanese halls.

This history follows those changes together. The central thread is how manufacturers developed different forms of play within successive sets of rules: reading the reels, waiting for a bonus lamp, following instructions during an assist mode, and progressing through an animated story.

Reviewed September 18, 2026. Dates below distinguish rule changes, approvals and market introductions where those occurred in different years. Sources are manufacturer archives and official industry-association publications.

The timeline at a glance

1960s–1980: the origins and “0th generation”

The Olympia predecessor adapted an American slot machine with stop buttons in 1964; authorized introduction followed in 1965. These are different milestones. [1]

The retrospective label 0th generation covers pre-1985 machines. Gemini brought three-medal, five-line play in 1977; Pachislo Pulsar used CPU and stepping-motor control in 1980. [1]

Yamasa’s own archive places Pachislo Pulsar in 1980 and New Pulsar in 1993. Seen together, they illustrate an enduring feature of this industry: a familiar series can span major technical changes. Recognizing the name alone does not tell you which generation or version you are looking at. [3]

1985–1990: the first three generations

Before nationwide standards, permission depended on prefectural rules. The law revision promulgated in August 1984 took effect on February 13, 1985, creating the framework associated with first-generation machines. This is why histories may mention both 1984 and 1985. [2]

The 1.5 generation strengthened board sealing; the second added credits; the third restricted concentration functions. Unauthorized modified machines (ura-mono) were not an approved generation. [1]

Kitadenshi’s archive provides concrete landmarks: Caster (August 1985), New Caster II (March 1987), Gulliver II (June 1988) and Apollo (October 1990). These are useful period examples rather than claims that each was the first machine nationwide. [4]

How to read generation labels

The Japanese suffix gōki (号機) refers to a generation of machines. A new number is not a difficulty level, a payout promise or a rating. Also distinguish three layers: formal machine regulations, official interpretations of those regulations, and the industry’s voluntary standards. Changes to the latter two can produce labels such as 6.1 or 6.5 without creating a new major regulatory generation. [2]

The fourth generation: several kinds of pachislot emerge

Universal’s company history records Cherry Bar as the first fourth-generation approval in 1992. Yamasa records New Pulsar in 1993. Approval and widespread hall introduction are different events, so a history starting the era in 1992 or describing its expansion from 1993 need not be contradictory. [3] [5]

The fourth generation should not be reduced to its most explosive late-period machines. Universal’s archive includes Cranky Condor (1995), Thunder V (1997), Hanabi (1998) and Oohanabi (1999). These names help explain why reels, recognizable symbols and familiar series identities remain part of pachislot culture. [5]

Another branch emphasized a clear bonus announcement. Kitadenshi dates the original Juggler to December 1996 and classifies it as a fourth-generation machine. Juggler therefore predates the sixth-generation and smart-slot eras by decades. Its historical place also shows why “older generation” does not automatically mean a complicated game with many modes. [4]

AT turns instructions into the central feature

Sammy dates Juuou (獣王) to 2001 and identifies it as a catalyst for the AT boom. Its Savanna Chance supplied instructions for collecting combinations that were otherwise difficult to select correctly. This helped make the assist sequence itself a major attraction, alongside the traditional bonus. [16]

Sammy’s original Hokuto no Ken (北斗の拳), released in 2003, combined AT and JAC games in its Battle Bonus. Character battles gave continuation a recognizable dramatic form. These examples explain why the late fourth generation is remembered both for output-oriented systems and for memorable presentation; a machine could join the two in a single experience. [16]

Meanwhile, bonus-stock systems created a different rhythm. Yamasa identifies King Pulsar (2001) as a stock machine. Instead of treating every bonus as an isolated event, these designs made the release of stored bonus opportunities central to the experience. Later uses of the word “stock” must be read carefully: a stock of future AT sets is not the same mechanism as storing bonus flags in a fourth-generation machine. [3] [6]

The period also established series that later returned in new forms. The industry association describes the 2023 Smart Pachislot Hokuto no Ken as reviving gameplay associated with the fourth-generation boom. This is an important thread in the history: manufacturers do not only introduce new stories; they also reinterpret experiences remembered by earlier players. [12]

Bonus, RT, AT, ART and stock: what actually changed?

These terms describe different mechanisms, not a simple ladder in which each newer term replaces everything before it. Understanding them makes the transitions between eras easier to follow. [6]

Pressing the buttons is therefore meaningful, but it does not let a player manufacture a winning lottery result. Follow the instructions for the particular machine rather than treating every screen marked “BONUS” as the same system. [6]

The fifth generation: rebuilding the game

July 2004 rules led to fifth-generation machines from 2005, beginning with Neon Genesis Evangelion. The fourth-generation replacement continued through 2007. [1]

The new era did not simply remove complexity and stay that way. Different combinations of bonuses, replay states and assist play gave designers ways to build extended sequences under the new framework. Yamasa’s history identifies Pachislot Monkey Turn (2011) with game-count additions during ART. That example makes the distinction tangible: the excitement could involve extending a mode, rather than only collecting the payout from a single bonus. [3]

Licensed storytelling became another major design thread. Universal lists SLOT Puella Magi Madoka Magica in 2013 and Basilisk: Kizuna in 2014. Yet the same archive records the launch of the A PROJECT line with Cranky Collection in 2013. Animated stories and renewed interest in traditional reel play developed alongside one another. [5]

Why the late fifth generation has decimal labels

The 5.5 and 5.9 phases introduced further constraints within the fifth generation. The 5.5 changes included bringing AT-related lottery control onto the main board; 5.9 introduced the advantageous-section framework. These changes matter because the sixth generation inherited a design conversation already underway, rather than inventing every restriction from scratch. [7]

Re:Zero − Starting Life in Another World belongs to the early sixth generation, not the fifth. Also, a franchise can have several pachislot adaptations: the generation of one Madoka Magica or Hokuto no Ken machine cannot be assigned to every later release bearing that name. [7] [12]

The sixth generation: shorter boundaries, then successive revisions

The revised rules took effect on February 1, 2018, and sixth-generation machines reached halls that year. Early machines worked with a 1,500-game advantageous-section limit and a 2,400-medal acquisition limit. Faster AT designs also appeared: stricter overall boundaries did not mean every machine became slower or simpler. [7]

An advantageous section is a defined operating interval, not the player’s whole visit. Its boundaries influence how a machine organizes normal play, entry into AT and the end of an extended sequence. Keep that interval separate from a day’s total spending or winnings.

What “2,400” does—and does not—mean

The 6.5 change is easiest to understand as accounting within one interval. If 1,000 medals have been lost in that same interval, a subsequent gain of 3,400 would leave a net gain of 2,400. This illustrates the rule; it does not predict a payout. Losses from previous intervals or earlier visits do not become a balance the machine owes the player. [8]

Consequently, “every machine stops after paying 2,400 medals in a day” is not an accurate description. Nor does an interval extension guarantee a longer winning sequence. The mechanism, entry conditions and termination rules of the particular model still matter. [8]

The end of the older era and the arrival of new formats overlapped: the association’s 2022 review records January 31 as the fifth-generation removal milestone, June’s 6.5 introductions and November’s smart-slot launch. Grouping all three events under “the sixth generation started in 2022” would erase the earlier machines introduced from 2018. [11]

Smart slots: what changed in November 2022?

Smart pachislot, commonly shortened to sumasuro (スマスロ), began hall operation on November 21, 2022. The first releases included Valvrave the Liberator, Baki and Smart Slot Reno Heaven. Smart slots are part of the sixth-generation era, not an automatic seventh generation. [11]

The most visible change is medal handling. A dedicated unit supplies electronic playing credits, so players do not feed physical medals into the machine or carry a tray of them away. Physical reels and stop buttons remain. At the end of play, credits are handled through the unit and its card system. [10]

Medal-less does not mean universally cashless. The official introduction explains play using banknotes at the dedicated unit. Whether a hall supports other payment methods is a separate question. The historical change was the removal of physical medal circulation at the machine, not a promise that visitors could pay with any credit card or mobile wallet. [10]

Behind the cabinet, the system reports machine-operation information through a management network. This supports monitoring and integrity controls; it is not a system that watches an individual player’s losses and dynamically changes their odds. The official technical explanation distinguishes reported machine data from personal information and settings. [9]

Smart hardware and game design are separate questions. A medal-less cabinet tells you how credits are handled. It does not, by itself, tell you the probability of a bonus, the complexity of the rules or how much a session will cost. The 2023 return of Hokuto no Ken also shows how new hardware can carry gameplay inspired by a much older generation. [12]

Bonus Trigger: a new branch, not a seventh generation

On August 23, 2024, a revised interpretation enabled Bonus Trigger (BT) designs. The association explains that this change did not replace the underlying sixth-generation regulations. First BT machines entered halls on June 2, 2025, including Smart Slot New Pulsar BT and LB Premium Umaibo. [13] [15]

BT develops the real-bonus side of pachislot. Its fixed-wager function can change the required bet after a bonus; bonus probabilities can differ with that wager. That creates ways to connect real bonuses. The official explanation distinguishes this mechanism from AT instructions and RT, rather than treating BT as another name for an assist mode. [13]

The association’s introductory examples describe several possible experiences: a pair of bonuses, a bonus followed by a smaller addition, or repeating bonus opportunities. These are design patterns, not universal specifications. To understand an actual BT machine, check which bonus activates the function, what happens next and what ends the sequence. [14]

By the association’s February 2026 review, BT had become an identifiable new category. It adds another route through the history: modern development is not solely about more elaborate AT. Real-bonus play can also gain new structures while keeping a different character from an animated assist sequence. [15]

What survived across the generations?

The examples above reveal three parallel traditions. This is a way to read the history, rather than an official classification of every machine.

• The reels as the main event. Symbols, recognizable arrangements and the act of stopping the reels can remain central even when cabinets and rules change.
• A clear moment of recognition. A simple bonus announcement offers a different appeal from navigating many screens and stages. The original Juggler belongs in the same history as later spectacle-heavy machines.
• An unfolding sequence. Assist modes, added games and recurring characters give manufacturers ways to present play as progression. A familiar franchise may return with a substantially different mechanism.

This coexistence is why the history is better understood as branching development than as a line from “basic” to “advanced.” A later machine is not necessarily more complicated, more skill-dependent or more suitable for a beginner. Reading its exact model name and game flow is more useful than judging it by its release era alone.

Common historical misunderstandings

Did pachislot begin in the 1980s?

No. The predecessor history reaches back to the 1960s. The electronic machines of around 1980 are a later milestone; the first nationally standardized generation followed in 1985. See the origins and the early generations.

Why do histories give different starting years for an era?

They may be dating a regulation, an approval, a first release or the removal of older machines. Those events need not happen in the same year. This page labels the distinction rather than treating a transition as a single launch day.

Are smart slots and Bonus Trigger the same thing?

No. Smart slots describe the medal-less machine system; BT describes a bonus-related function. Hardware format, bonus mechanism and regulatory generation answer different questions.

Does knowing the history make a win predictable?

No. History helps explain terminology and design choices. It does not tell you the result of a future game or make a loss recoverable. For practical preparation, read how to start playing, the guide to game states and responsible play.

Sources and further reading

The historical record here uses manufacturer archives and Nichidenkyo, the Japanese pachislot manufacturers’ association. Pachislot Summit ONLINE is operated by Nichidenkyo. Japanese model names may be romanized or translated for English readers; dates refer to the specific original or version named, not an entire franchise.

1. Nichidenkyo: pachislot history — origins, early generations and the fourth-to-fifth-generation transition.
2. Nichidenkyo official column: regulations, interpretations and voluntary standards — the 1984/1985 distinction and generation terminology.
3. Yamasa Next: corporate history — Pulsar, King Pulsar and Monkey Turn milestones.
4. Kitadenshi: machine archive — dated early-generation examples and the original Juggler.
5. Universal Entertainment: company history — fourth-generation examples, A PROJECT and licensed releases.
6. Nichidenkyo official glossary — bonus, replay and assist terminology.
7. Nichidenkyo official column: the development of sixth-generation machines — late fifth-generation changes and early sixth-generation revisions.
8. Nichidenkyo official column: 6.5-generation changes — interval length and net-difference accounting.
9. Nichidenkyo official column: the smart-slot system — technical architecture and operating-data reporting.
10. Nichidenkyo: official smart-slot introduction — electronic credits, dedicated units and player operation.
11. Nichidenkyo official review of 2022 — fifth-generation transition, 6.5 introduction and November 21 smart-slot launch.
12. Nichidenkyo official review of 2023 — the return of Hokuto no Ken on smart hardware.
13. Nichidenkyo official column: Bonus Trigger interpretation and 6.6 — August 2024 interpretation and interval changes.
14. Nichidenkyo official introduction to BT game designs — examples of real-bonus sequences.
15. Nichidenkyo official BT review, February 2026 — June 2, 2025 introduction and subsequent development.
16. Sammy: corporate and product history — Juuou (2001), original Hokuto no Ken (2003) and their assist systems.

Continue with the pachislot glossary or choose a specific model in the machine guides.