> I always wondered in those days why the disk drives for 8-bit computers were so crazy expensive. In Holland they cost more than the computers they were meant for.
The mechanics were also somewhat expensive. In Brazil, an Apple II drive was often as expensive as an Apple II clone.
What makes the intelligent drives a great idea is how easy it is to emulate them - you emulate a nice protocol. When you have to emulate, say, an Apple II drive, you need to emulate the delays the drive mechanics introduce, as well as the head electronics, because the Apple II's 6502 is reading the head and assembling the bits. That's also why accelerating an Apple II requires you to slow it down for a longer time every time it accesses the IO region - because the disk needs to revolve in the exact time the 6502 takes to run some amount of code. With an intelligent peripheral, it doesn't matter you don't wait several seconds between commands, as long as you only issue them at the required speeds.
The mechanics were also somewhat expensive. In Brazil, an Apple II drive was often as expensive as an Apple II clone.
What makes the intelligent drives a great idea is how easy it is to emulate them - you emulate a nice protocol. When you have to emulate, say, an Apple II drive, you need to emulate the delays the drive mechanics introduce, as well as the head electronics, because the Apple II's 6502 is reading the head and assembling the bits. That's also why accelerating an Apple II requires you to slow it down for a longer time every time it accesses the IO region - because the disk needs to revolve in the exact time the 6502 takes to run some amount of code. With an intelligent peripheral, it doesn't matter you don't wait several seconds between commands, as long as you only issue them at the required speeds.