 | This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Microvision" – news ·newspapers ·books ·scholar ·JSTOR(March 2023) (Learn how and when to remove this message) |
 | |
 A Microvision withBlock Buster cartridge inserted | |
| Also known as | Milton Bradley Microvision MB Microvision |
|---|---|
| Manufacturer | Milton Bradley Company |
| Type | Handheld game console |
| Generation | Second generation |
| Release date | November 1979; 46 years ago (1979-11) |
| Introductory price | US$49.99 (equivalent to about $217 in 2024) |
| Discontinued | 1981 |
| Media | ROM cartridges |
| CPU | Intel 8021/TI TMS1100 (on cartridge) clocked at 100 kHz |
| Memory | 64 bytesRAM, 2KROM |
| Display | 16 × 16pixels resolution |
| Power | 1 × 9V battery (TMS1100 processors), 2 × 9V battery (Intel 8021 processors) |
TheMicrovision (akaMilton Bradley Microvision orMB Microvision) is the firsthandheld game console that used interchangeablecartridges[1][2] and in that sense is reprogrammable.[3] It was released by theMilton Bradley Company in November 1979[4] for a retail price of $49.99,[5][6] equivalent to $221.00 in 2025.
The Microvision was designed by Jay Smith, the engineer who later designed theVectrex video game console.[2] The Microvision's combination of portability and a cartridge-based system led to moderate success, with Smith Engineering grossing $15 million in the first year of the system's release. However, its small game library, its small screen, and a lack of support from established home video game companies led to its discontinuation in 1981.[7] According toSatoru Okada, the former head ofNintendo'sR&D1 Department, the Microvision inspired theGame Boy, the follow-up toGame & Watch, after Nintendo designed around Microvision's limitations.[8]
_-_Gameplay_screenshot.svg)
Unlike most later consoles, the Microvision did not contain an onboard processor (CPU). Instead, each game included its own processor contained within the removable cartridge.[9][10][11] This meant that the console itself effectively consisted of the controls,LCD panel and LCD controller.[9][11]
The processors for the first Microvision cartridges were made with bothIntel 8021 (cross-licensed bySignetics) andTexas InstrumentsTMS1100 processors. Due to purchasing issues, Milton Bradley switched to using TMS1100 processors exclusively, including reprogramming the games that were originally programmed for the 8021 processor. The TMS1100 was a more primitive device, but offered more memory and lower power consumption than the 8021. First-revision Microvisions needed two batteries due to the 8021's higher power consumption, but later units (designed for the TMS1100) only had one active battery holder. Even though the battery compartment was designed to allow the two 9-volt batteries to be inserted with proper polarity of positive and negative terminals, when a battery was forcefully improperly oriented, while the other battery was properly oriented, the two batteries would be shorted and overheat. The solution was to remove terminals for one of the batteries to prevent this hazard. Due to the high cost of changing production molds, Milton Bradley did not eliminate the second battery compartment, but instead removed its terminals and called it a spare battery holder.[citation needed]
Microvision units and cartridges are now somewhat rare.[12][13] Those that are still in existence are susceptible to three main problems: "screen rot,"ESD damage, and keypad destruction.
The manufacturing process used to create the Microvision'sLCD was primitive by modern standards. Poor sealing and impurities introduced during manufacture have resulted in the condition known asscreen rot. The liquid crystal spontaneously leaks and permanently darkens, resulting in a game unit that still plays but is unable to properly draw the screen. While extreme heat, which can instantly destroy the screen, can be avoided, there is nothing that can be done to prevent screen rot in most Microvision systems.[3]
A major design problem on early units involves the fact that themicroprocessor (which is inside the top of each cartridge) lacksESD protection and is directly connected to the copper pins which normally connect the cartridge to the Microvision unit. If the user opens the protective sliding door that covers the pins, the processor can be exposed to anyelectric charge the user has built up. If the user has built up a substantial charge, the discharge can jump around the door's edge or pass through the door itself (dielectric breakdown). The low-voltageintegrated circuit inside the cartridge is extremely ESD sensitive, and can be destroyed by an event of only a few dozen volts which cannot even be felt by the person, delivering a fatal shock to the game unit. This phenomenon was described in detail byJohn Elder Robison (a former Milton Bradley engineer) in his bookLook Me in the Eye; according to Robison, up to 60% of units were returned as defective during the 1979 holiday season, causing significant panic among Milton Bradley staff and prompting extensive modifications to both later Microvision units (which were his own design) and Microvision factories to better dispel stray static charges.[14]
The Microvision unit had a twelve-buttonkeypad, with the switches buried under a thick layer of flexible plastic. To align the user's fingers with the hidden buttons, the cartridges had cutouts in their bottom (over the keypad). As different games required different button functions, the cutouts were covered with a thin printed piece of plastic, which identified the buttons' functions in that game. The problem with this design is that pressing on the buttons stretched the printed plastic, resulting in the thin material stretching and eventually tearing. Having long fingernails exacerbated the condition. Many of the initial games were programmed to give feedback of the keypress when the key was released instead of when the key was pressed. As a result, users may press on the keypad harder because they are not being provided with any feedback that the key has been pressed. This resulted from a keypad used for prototyping being different from the production keypad; the prototyping keypad had tactile feedback upon key pressing that the production units lacked.[citation needed]
| This sectionneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources in this section. Unsourced material may be challenged and removed. Find sources: "Microvision" – news ·newspapers ·books ·scholar ·JSTOR(August 2020) (Learn how and when to remove this message) |
While the game cartridge plastic cases were beige colored in the USA, in Europe they came in a variety of different colors, and the games were numbered on the Box. The age range in Europe for the console and its games was from 8 to 80 years old or 8 to Adult.
There were12 titles known to have been released.
| # | US title | Overseas titles | Game number (EU) | Release date | Microprocessor/s[15] | PCB Revision(s) |
|---|---|---|---|---|---|---|
| 1 |  Block Buster4952 |  Block Buster Block Buster Block Buster Block Buster Casse Brique | 1 1 1 1 1 | November 1979 | TI MP3450A | 4952 REV A 4952-56 REV A 4952-79 REV B |
| 2 | Bowling 4972 | BowlingBowlingBowlingBowlingBowling | 2 2 2 2 2 | November 1979 | TI MP3475NLL | 4952 REV A |
| 3 | Connect Four 4971 | Connect 44 GewinntVier Op'n RijForza 4Puissance 4 | 5 5 5 5 5 | November 1979 | Signetics Intel 8021 TI MP3481NLL | 4971 REV C 4952 REV - |
| 4 | Pinball 4974 | PinballPinballFlipperFlipperFlipper | 4 4 4 4 4 | November 1979 | TI MP3455NLL | 4952 REV A |
| 5 | Mindbuster 4976 | N/A | N/A | 1979 | TI MP3457NLL | 4952 REV A |
| 6 | Star Trek: Phaser Strike (later justPhaser Strike) 4973 | Shooting StarShooting StarShooting StarShooting StarShooting Star | 3 3 3 3 3 | 1979 | TI MP3454NLL | 4952 REV A |
| 7 | Vegas Slots 4975 | N/A | N/A | 1979 | TI MP3474-NLL | 4952-56 REV - |
| 8 | Baseball 4974 | N/A | N/A | 1980 | TI MP3479-N1NLL | 4952-56 REV - |
| 9 | Sea Duel 4064 | Sea DuelSee-DuellDuelDuello Sul MareBataille Navale (Battleship) | 6 6 6 6 6 | 1980 | TI MP3496-N1 | 4952-56 REV - |
| 10 | Alien Raiders 4176 | Space BlitzBlitzBlitzBlitzBlitz | 7 7 7 7 7 | 1981 | TI M34009-N1 | 4952-79 REV B |
| 11 | Cosmic Hunter 4177 | N/A | N/A | 1981 | TI M34007-N1 | 4952-79 REV B |
| 12 | N/A | Super Block BusterSuper Blockbuster 611497800Super Block BusterSuper Casse Brique (Super Brick Breaker) 611497801 | 8 8 8 8 | 1982 | TI M34047-N2LL | 7924952D02 Rev B |
| 13 | Barrage* | ? | ? | Unreleased (supposed to be released in 1982) | ? |
{{cite web}}: CS1 maint: multiple names: authors list (link)the console itself is nothing more than controls, LCD panel and a controller chip for the LCD panel. Each cartridge contains the microprocessor, which happens to have a small amount of ROM space on it that MB loaded the game code onto.
In fact, it was the cartridge itself that contained the CPU, and just to confuse everyone two different ones were used.
The main unit was little more than a housing for the display, batteries, switches and controller, while the brains of each game was a combined microprocessor/memory chip inside the clip-on cartridge.
{{cite web}}: CS1 maint: numeric names: authors list (link)
