zippy - yet another serial fastloader
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- JonBrawn
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Re: zippy - yet another serial fastloader
It's a Pi1541, nothing special done to it.
Working on FPGA replacement for 6560/6561
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- Mike
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Re: zippy - yet another serial fastloader
To make things clear: JiffyDOS requires both computer and drive understand the JD protocol. Normally this involves replacing the KERNAL ROM in the computer and the DOS ROM in the drive. Instead of replacing the KERNAL ROM, zippy takes care for that on the computer's side by re-implementing the JD protocol with own routines.JonBrawn wrote:It's a Pi1541, nothing special done to it.
It should be noted that the Pi1541 is a complete emulation of the CBM drives, including the drive CPU, and it only provides the JiffyDOS protocol if it is actually run with the floppy side ROM dump of JiffyDOS - unlike the SD2IEC devices, which again re-implement the JD protocol from the specification.
Running the Pi1541 with the ROM dump of the standard CBM DOS 2.6 is not sufficient in this case.
Jim Brain sells JiffyDOS - you need to state for which drive and for which computer you need it. To be more precise, you would need the JiffyDOS 1541/1541C/1541II DOS ROM Overlay Image for the Pi1541: https://store.go4retro.com/jiffydos-154 ... lay-image/
An alternative to JiffyDOS would be one of the few old-style drive speeders, which load own routines into the floppy RAM and replace the bus transfer routines at least, for a faster protocol. For NTSC, I only know about Compute!'s TurboDisk, which had been discussed here in Denial quite some years ago. I'd follow up in the other thread.
- JonBrawn
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Re: zippy - yet another serial fastloader
OK, that's really useful information, thanks.
Working on FPGA replacement for 6560/6561
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- MrSterlingBS
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Re: zippy - yet another serial fastloader
Hi,
i have used Mike‘s Minigrafik DiaShow to compare some speed loaders. You can See the different directly on the screen.
BR
Sven
i have used Mike‘s Minigrafik DiaShow to compare some speed loaders. You can See the different directly on the screen.
BR
Sven