question: why did old games need batteries in the cartridge to save rather than using the consoles power?
comment: The console's power would be unavailable when the console was off or the cartridge removed from the system. Because the technology used to maintain save files required a power source, a battery was the only option.
passages: Even though third-party rechargeable batteries were available for the battery-hungry alternatives to the Game Boy, these batteries employed a nickel-cadmium process and had to be completely discharged before being recharged to ensure maximum efficiency; lead-acid batteries could be used with automobile circuit limiters (cigarette lighter plug devices); but the batteries had mediocre portability. The later NiMH batteries, which do not share this requirement for maximum efficiency, were not released until the late 1990s, years after the Game Gear, Atari Lynx, and original Game Boy had been discontinued. During the time when technologically superior handhelds had strict technical limitations, batteries had a very low mAh rating since batteries with heavy power density were not yet available.
   Early cartridges had storage limitations which grew in size as the technology developed. They provided more security against third party developers and the illegal copying of games. Some could be partially re-writable allowing for games to save their data to the cartridge itself meaning no extra saving media was required.
  
  While cartridges became less popular with the introduction of disc based media, they are still popular to use for handheld consoles and are still in use on consoles in later generations such as the Nintendo Switch.
  
  Section::::Technology.:Storage.:Disc.
   In 1991, Nintendo provided an add-on called the "Super NES Counter Tester" that tests Super Nintendo components and games. The SNES Counter Tester is a standard SNES on a metal fixture with the connection from the back of the SNES re-routed to the front of the unit. These connections may be made directly to the test station or to the TV, depending on what is to be tested.
  
  Section::::Games.
  
  The Nintendo Entertainment System has a number of groundbreaking games. "Super Mario Bros." pioneered side-scrollers and "The Legend of Zelda" helped popularize battery-backed save functionality.
  
  Section::::Games.:Game Pak.
   With the advent of optical based media at the tail end of the 16-bit era, data could not be stored on the game media, and a saved game required the introduction of non-volatile memory to the console either in the form of internal memory or memory cards (both of which were introduced with the Sega CD) which stored game data once the system was powered off; passwords avoided the need for this.
   On later cartridge-based console games, such as "Kirby's Adventure" and "The Legend of Zelda", saved games were stored in battery-backed RAM on the game cartridge itself. In recent consoles, which use disc-based media for storing games, saved games are stored in other ways, such as by use of memory cards or internal hard drives on the game machine itself.
  
  Some games do not save the player's progress towards completing the game, but rather high scores, custom settings, and other features. The first game to save the player's score was Taito's seminal 1978 shoot 'em up title "Space Invaders".
   Nintendo Power (cartridge)
  
  The flash ROM cartridge is a Japan-only peripheral which was produced by Nintendo for the Super Famicom and the Game Boy. The now defunct service allowed owners to download Super Famicom and Game Boy games onto a special flash memory cartridge for a lower price than that of the full cartridge.
   This era also saw a revival of handheld consoles, which were absent in the prior generation. Nintendo's Game Boy, a portable released in 1989 with monochromatic 2D graphics and 35-hours battery life, became widely popular in the world and sold much more than its three competitors, the Atari Lynx, Sega's Game Gear and NEC's Turbo Express, released in Japan in North America until 1991. Despite these three consoles having much more sophisticated 16-bit graphics (similar to home consoles of the time), they had limited battery life. The other consoles also had scarce game libraries compared to over one thousand games released for the Game Boy, including best-selling titles "Pokémon Red" and "Blue", and which inspired an entire line of portable machines that continued through the following two generations.
   In the fifth generation of video game consoles, passwords retained practical use in conserving memory blocks. Platform and puzzle games often required no data to be preserved other than the level achieved – which was easily encoded in a simple password – and thus using one of the limited blocks for this data was seen as wasteful. More importantly, some consoles of the time, such as the PlayStation and Jaguar CD, had no memory available for saves out of the box, and the need to purchase separately sold memory cards could be a deterrent to purchasing a game.
   The late 1980s and early 1990s saw the beginnings of the handheld game console industry as we know it, after the demise of the Microvision. As backlit LCD game consoles with color graphics consume a lot of power, they were not battery-friendly like the non-backlit original Game Boy whose monochrome graphics allowed longer battery life. By this point, rechargeable battery technology had not yet matured and so the more advanced game consoles of the time such as the Sega Game Gear and Atari Lynx did not have nearly as much success as the Game Boy.
   Section::::Rationale and history.
  
  Passwords were used when storage was either impossible or expensive. On early ROM cartridges, games could not be saved without an additional memory card being integrated into the game, significantly increasing (often doubling) the manufacturing cost. By using passwords, nothing needed to be written on the cartridge, as the password itself contained all the information needed to continue the game, and thus a memory card was not necessary, lowering costs. These costs were particularly a concern on low volume titles by smaller third-party developers.
   MSX systems generally did not have a built-in disk drive, so games were published mainly on cartridge and cassette tape. Sony created a battery backed RAM cartridge the HBI-55 "data cartridge" for some computers in their "Hit-Bit" line of MSX systems, that could be used to store programs or data as an alternative to cassette tapes.
   Each video game is stored on a plastic cartridge, officially called a "Software Cartridge" by SNK. The cartridge provides the code and game data to the console's CPU. Some cartridges include a small battery with SRAM, flash memory chip, or EEPROM, which allows game data to be saved when the console is turned off. If the battery runs out in a cartridge, then the save data will be lost, however, it is possible to replace the battery with a new battery. To do this, the cartridge must be unscrewed, opened up, and the old battery would be removed and replaced. This may require desoldering the dead battery and soldering the replacement in place. SNK used round, flat watch batteries for saving information on the cartridges.
   The relative complexity and inconvenience of storing game state information on early home computers (and the fact that early video game consoles had no non-volatile data storage) meant that initially game saves were represented as "passwords" (often strings of characters that encoded the game state) that players could write down and later input into the game when resuming.
   A 320-page book called "Playing with Power: Nintendo NES Classics", published by Prima Games, was released the same day as the console; the book is a guide to some of the games included on the system. Nintendo of America brought back the Nintendo Power Line as an automated phone hotline from November 11 to 13 as a celebration of the launch of the system.
  
  Section::::Hardware.:Included games.
   Other handheld consoles released during the fourth generation included the TurboExpress, a handheld version of the TurboGrafx-16 released by NEC in 1990, and the Game Boy Pocket, an improved model of the Game Boy released about two years before the debut of the Game Boy Color. While the TurboExpress was another early pioneer of color handheld gaming technology and had the added benefit of using the same game cartridges or 'HuCards' as the TurboGrafx16, it had even worse battery life than the Lynx and Game Gear – about three hours on six contemporary AA batteries – selling only 1.5 million units.
   BULLET::::- Battery life: 10 hours continuous play with light on, 18 hours with light off; needs at most 3 hours recharging.
   Often a timer charger and set of batteries could be bought as a bundle and the charger time was set to suit those batteries. If batteries of lower capacity were charged then they would be overcharged, and if batteries of higher capacity were charged they would be only partly charged. With the trend for battery technology to increase capacity year on year, an old timer charger would only partly charge the newer batteries.
   BULLET::::- STacy: a portable (but definitely not laptop) version of the ST with the complete ST keyboard, an LCD screen simulating 640x400 hi-res, and a mini-trakball intended mostly for travellers and musicians because of the backlit screen and its built-in midi ports. Originally designed to operate on 12 standard C cell flashlight batteries for portability, when Atari finally realized how quickly the machine would use up a set of batteries (especially when rechargeable batteries of the time supplied insufficient power compared to the intended alkalines), they simply glued the lid of the battery compartment shut.
   Section::::1980s.:Handheld LCD games.
  
  In 1979, Milton Bradley Company released the first handheld system using interchangeable cartridges, Microvision. While the handheld received modest success in the first year of production, the lack of games, screen size and video game crash of 1983 brought about the system's quick demise.
   BULLET::::- Atari HPC-402 Mains adapter 220 V
  
  BULLET::::- Atari HPC-406 Parallel cable
  
  BULLET::::- Atari HPC-407 Serial cable
  
  BULLET::::- Atari HPC-408 Parallel printer cable
  
  BULLET::::- Atari HPC-409 Null modem cable
  
  BULLET::::- Atari HPC-501 OTPROM adapter 512 KBit
  
  BULLET::::- Atari HPC-502 OTPROM adapter 1 MBit
  
  BULLET::::- Atari HPC-701 ROM card "Utility"
  
  BULLET::::- Atari HPC-702 ROM card "Finance"
  
  BULLET::::- Atari HPC-703 ROM card "Science"
  
  BULLET::::- Atari HPC-704 ROM card "File Manager"
  
  BULLET::::- Atari HPC-705 ROM card "Power BASIC"
  
  BULLET::::- Atari HPC-709 ROM card "Instant Spell"
  
  BULLET::::- Atari HPC-711 ROM card "U.S. Traveller's Guide)"
  
  BULLET::::- Atari HPC-713 ROM card "Hyperlist"
  
  BULLET::::- Atari HPC-715 ROM card "Language Translator"
   Games developed during this generation were native components of the consoles and unlike other generations, they were not contained on removable media that the user could switch out. There were a number of methods used to create variation in games such as the inclusion of external accessories and cartridges that could alter the way the game played. Graphical capabilities consisted of simple geometry such as dots, lines or blocks that would occupy only a single screen and wouldn't be capable of more than two colours (usually black and white) until later in the generation. Audio capabilities were limited with some consoles having no audio at all.
   The processors for the first Microvision cartridges were made with both Intel 8021 (cross licensed by Signetics) and Texas Instruments TMS1100 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 they would 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 the spare battery holder.
   An alternative device was the Super Flash, by Tototek, which allowed for multiple games to be burned onto a flash memory chip of cartridge (allowing up to 48Mbits). This chip was the mask ROM for the Super Flash development cartridge; it was easy to use and had a user interface on the computer end; simply plug in the Super Flash cartridge and upload the games one wanted. This allowed users to make a SNES game and play it in an actual cartridge rather than a floppy disk.
  
  Section::::First through fourth generation consoles.:TurboGrafx-16/PC Engine.
   Entex released two handheld systems in the second generation, the Select-A-Game and the Adventure Vision. There were 6 games available for the Select-A-Game but it was only available for a year until focus shifted to the Adventure Vision which was released in the following year.
   Some of the more well-known handheld games of the LCD era are the Game & Watch series by Nintendo and the games by Tiger Electronics, and many titles from other companies were also popular, especially conversions of arcade games. New games are still being made, but most are based on relatively simple card and board games.
  