Why didn't Commdore implement floppy disk speeder with C64?

[C64XL]

One of the biggest drawback of C64 was the unreliable and super slow floppy drive. But there are a lot of 3rd party floppy speeder available. Why didn't Commodore implement it to speed up their floppy disk? I think it will make the machine even more popular if they did.

[rmzalbar]

They had a deadline to release the machine. Shortly before that deadline, the designed-in hardware disk speeder scheme (serial burst mode) fell through due to a hardware bug in the VIA that is used in the 1541 disk drive, and also a board layout bug in the C64. It was too late to fix this, so at the last minute they fell back to a software CPU-driven "bit-banging" technique that was extremely slow but very simple to implement and had already proven reliable on the VIC-20. The aftermarket software disk-speeder hacks that came along later, Fastload and JiffyDOS etc, were either not conceived of yet by Commodore, or else they simply didn't have time to develop one into practice. In any case, once the hardware was released, they couldn't retroactively introduce it as it would revise the already published spec and damage vendors by causing compatibility problems with earlier software and hardware built on that spec.

When the C128 came along they were free to implement burst mode for the 128, but note that this feature is not permitted when running the 128 in C64 mode even though the hardware can do it. Burst mode also requires a 1570 or 1571, which use CIA instead of VIA. Presumably they would have implemented CIA into the 1541 if they had discovered the bug early enough.

[C64XL]

Thanks for the reply. Commodore 64 had a long life cycle. I wonder why they don't try to integrate the floppy speeder in later production. Some 3rd party solutions provided very good compatibility. It should be doable. C64 was ahead of Apple II in almost everything except the painstaking slow disk drive.

[rmzalbar]

I'm sure they could have implemented it in later C64, but presentations I've seen by ex-commodore engineers suggest they were very careful to ensure absolute 100% compatibility both forwards and backwards, and that is why there were never any new features added to C64 models. In any case, the aftermarket did such a thorough job of providing options, that it wasn't something that needed urgent attention by them.

Commodore did very little hardware evolution on their platforms. On the C64, all changes were for adapting to newer production processes and reducing cost. The Amiga chipset was allowed to advance even at the cost of compatibility, but even there, relatively little progress.