The Microvision (aka Milton Bradley Microvision or MB Microvision) is the first handheld game console that used interchangeable cartridges and in that sense is reprogrammable. for a retail price of $49.99, equivalent to $221.00 in 2025.
The Microvision was designed by Jay Smith, the engineer who later designed the Vectrex video game console. According to Satoru Okada, the former head of Nintendo's R&D1 Department, the Microvision inspired the Game Boy, the follow-up to Game & Watch, after Nintendo designed around Microvision's limitations.
Production
thumb|left|140px|Screenshot of Block Buster, which came packaged with the Microvision
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. Those that are still in existence are susceptible to three main problems: "screen rot," ESD damage, and keypad destruction.
Screen rot
The manufacturing process used to create the Microvision's LCD was primitive by modern standards. Poor sealing and impurities introduced during manufacture have resulted in the condition known as screen 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.
ESD damage
A major design problem on early units involves the fact that the microprocessor (which is inside the top of each cartridge) lacks ESD 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 any electric 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-voltage integrated 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 by John Elder Robison (a former Milton Bradley engineer) in his book Look 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.
Keypad destruction
The Microvision unit had a twelve-button keypad, 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.
Technical specifications
upright|thumb|The PCB of a Sea Duel game cartridge, showing the TI3496 processor from the TMS1100 family
- CPU: Intel 8021/TI TMS1100 (on cartridge)
- Screen type and resolution: 16 × 16 pixel LCD
!PCB Revision(s)
|-
| 1 || Block Buster
4952
| Block Buster<br/> Block Buster<br/> Block Buster<br/> Block Buster<br/> Casse Brique || 1<br/> 1<br/> 1<br/> 1<br/> 1 || || TI MP3450A
|4952 REV A
4952-56 REV A
4952-79 REV B
|-
| 2 || Bowling
4972
| Bowling<br/> Bowling<br/> Bowling<br/> Bowling<br/> Bowling || 2<br/> 2<br/> 2<br/> 2<br/> 2 |||| TI MP3475NLL
|4952 REV A
|-
| 3 || Connect Four
4971
| Connect 4<br/> 4 Gewinnt<br/> Vier Op'n Rij<br/> Forza 4<br/> Puissance 4 || 5<br/> 5<br/> 5<br/> 5<br/> 5|||| Signetics Intel 8021
TI MP3481NLL
|4971 REV C
4952 REV -
|-
| 4 || Pinball
4974
| Pinball<br/> Pinball<br/> Flipper<br/> Flipper<br/> Flipper || 4<br/> 4<br/> 4<br/> 4<br/> 4 |||| TI MP3455NLL
|4952 REV A
|-
| 5 || Mindbuster
4976
|N/A ||N/A |||| TI MP3457NLL
|4952 REV A
|-
| 6 || Star Trek: Phaser Strike<br/>(later just Phaser Strike)
4973
| Shooting Star<br/> Shooting Star<br/> Shooting Star<br/> Shooting Star<br/> Shooting Star || 3<br/> 3<br/> 3<br/> 3<br/> 3|||| TI MP3454NLL
|4952 REV A
|-
| 7 || Vegas Slots
4975
|N/A ||N/A ||||TI MP3474-NLL
|4952-56 REV -
|-
| 8 || Baseball
4974
|N/A ||N/A ||||TI MP3479-N1NLL
|4952-56 REV -
|-
| 9 || Sea Duel
4064
| Sea Duel<br/> See-Duell<br/> Duel<br/> Duello Sul Mare<br/> Bataille Navale (Battleship) || 6<br/> 6<br/> 6<br/> 6<br/> 6 ||||TI MP3496-N1
|4952-56 REV -
|-
| 10 || Alien Raiders
4176
| Space Blitz<br/> Blitz<br/> Blitz<br/> Blitz<br/> Blitz || 7<br/> 7<br/> 7<br/> 7<br/> 7 ||||TI M34009-N1
|4952-79 REV B
|-
| 11 || Cosmic Hunter
4177
|N/A ||N/A ||||TI M34007-N1
|4952-79 REV B
|-
| 12 || N/A || Super Block Buster<br/> Super Blockbuster 611497800<br /> Super Block Buster<br /> Super Casse Brique (Super Brick Breaker) 611497801
| 8<br/> 8<br/> 8<br/> 8 ||||TI M34047-N2LL
|7924952D02 Rev B
|-
|style="background:#FFE8E8; | 13 ||style="background:#FFE8E8; | Barrage* || style="background:#FFE8E8; " |? ||style="background:#FFE8E8; |?||style="background:#FFE8E8; |Unreleased<br/>(supposed to be released in 1982)||?
|
|}
Reviews
- 1980 Games 100 in Games
- 1981 Games 100 in Games
See also
- Mattel Auto Race
- Vectrex