Post by gsteemso on Jan 19, 2016 5:25:21 GMT
As I understand it, the reason Commodore switched away from IEEE-488 as a standard interface is that the cables were ridiculously expensive—and on top of that, they were for a time only available from one manufacturer, which inconveniently stopped producing them for a while in the late 1970s, leaving Commodore customers with shiny new PET computers but no way to connect them to the floppy drives and printers (themselves VERY costly) that were supposed to work with them. On the other hand, equipment as expensive as those drives was not something anyone with more sense than budget would just discard after only a few years, so the IEEE-488 carts for C64/128 were made available as a backwards compatibility measure.
Of course, the total sales of all those IEEE-488 peripherals added together equalled only a small fraction of the subsequent C64/128 sales, and not all who bought the one necessarily then bought the other (nor did those who HAD bought both then necessarily buy the interface cart), so the net market penetration of those specific cartridges was always going to appear rather low when viewed in comparison to the enormous sales success of C64s (especially as later extended even further by the less extreme sales success of C128s).
EDIT: I nearly forgot to mention, the reason Commodore used a moderately customized version of IEEE-488 on their computers in the first place is that, at the time, it was one of the de facto standard interfaces for scientific equipment. HP equipment only stopped including it as a matter of course in the 90s some time, though their consumer PCs had dropped it quite a while earlier. It is still very widely used in certain technical environments even today. Presumably some number of labs and workshops bought those cartridges for their later-model Commodore 8-bitters too, but the numbers are unlikely to have been high enough to materially affect my analysis above.
Of course, the total sales of all those IEEE-488 peripherals added together equalled only a small fraction of the subsequent C64/128 sales, and not all who bought the one necessarily then bought the other (nor did those who HAD bought both then necessarily buy the interface cart), so the net market penetration of those specific cartridges was always going to appear rather low when viewed in comparison to the enormous sales success of C64s (especially as later extended even further by the less extreme sales success of C128s).
EDIT: I nearly forgot to mention, the reason Commodore used a moderately customized version of IEEE-488 on their computers in the first place is that, at the time, it was one of the de facto standard interfaces for scientific equipment. HP equipment only stopped including it as a matter of course in the 90s some time, though their consumer PCs had dropped it quite a while earlier. It is still very widely used in certain technical environments even today. Presumably some number of labs and workshops bought those cartridges for their later-model Commodore 8-bitters too, but the numbers are unlikely to have been high enough to materially affect my analysis above.