Macintosh PowerBook 520c (1994)

The PowerBook 500 series (codenamed Blackbird, which it shared with the older Macintosh IIfx) is a range of Apple Macintosh PowerBook portable computers first introduced by Apple Computer with the 540c model on May 16, 1994. The 500 series was the first laptop computer to use a trackpad instead of a trackball as a built-in pointing device and the first to have Ethernet networking built-in. It was the first PowerBook series to use a Motorola 68LC040 CPU (simultaneous with Duo 280) and be upgradeable to the PowerPC architecture via a swap out CPU daughter card (with the PowerPC and 68040 upgrades for sale), use 9.5" Dual Scan passive color/B&W displays, 16bit stereo sound with stereo speakers, have an expansion bay, PC Card capability, two battery bays (and a ten minute sleep/clock battery, which allowed for main batteries to be swapped out while in sleep mode), full size keyboard with F1-F12 function keys, be able to sleep while connected to an external monitor and have a battery contact cover included on the actual batteries. It included a single serial port which could be to connect to a serial printer or a network via Apple's LocalTalk. In another first, it also included an AAUI port for connecting to non-LocalTalk (usually Ethernet) networks. It was introduced on May 16, 1994 with the expensive active matrix LCD PowerBook 540c and 540, with the passive matrix 520c and 520 soon after. 

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