APPLE SCSI

Unlike in the PC world, the Apple standardised on one drive interface, SCSI. Also, Apple standardised on a 25 pin connector for external connections. However, Apple decided not to implement the complete ANSI spec., so one must be careful that peripherals used are certified to work with Apple's SCSI bus. Apple also developed it's own pin-configuration. The Apple and Future Domain 25-pin SCSI connectors are as close to "Standards" as there are in the world of PCs. But the real ANSI Standard called for a 50 pin connector commonly referred to as a "Centronics" type (made popular by the Centronics printer company). Instead of the 25 staggered pins of the Apple & Future Domain type connectors, the Centronics type uses 2 parallel rows of 25 pins. This arrangement allows the use of extra grounds for better isolation.