heh SD for c64...cool ####...

_________________
See my blog and collection website! . https://www.blog.amigaguru.com

Quote:

you can access any MMC or SD card that's FAT16-formatted - up to the size of 4GB!

Hmm.. Fat16 has a 2GB limit... how do you format it at 4GB?

Well there's one thing that this lot proves, what with seeing a C64 browsing the net, and now seeing that it can have 4Gb of storage:

I thought I was a die-hard, sticking with Amiga when most others had migrated to PCs, but seeing that some people are made of even tougher stuff, still developing for C64s makes us using an Amiga look positively sane

These people at Individual Computers are completely bonkers

This is EXACTLY the sort of innovative people we need in the Amiga community, who can push things to their limits, then push some more. Nice one guys

Quote:

Hmm.. Fat16 has a 2GB limit... how do you format it at 4GB?

2 partitions.

_________________
Ya Husayn!

The C64 has been able to use SCSI drives (harddrives, CD-ROMs and ZIP-drives) since the early 90's with the CMD-HD unit which connects like any other serial Commodore compatible device. The IDE64 which connects to the cardridge slot has been available since 1997, constantly being updated and allowing people to use standard IDE-devices with the C64. The latest version even has a CF (Compact Flash) slot for those who want silent mass storage (or don't have any external PSU for a IDE harddrive or CD-ROM). The IDE64 is also fully SuperCPU compatible, which is a big plus, and an ethernet addon will be available in february 2005. The RR-Net does work with a SuperCPU too if set in flash mode, it would be nice if this unit directly would support the SuperCPU though...

w00t!

Quote:

Hmm.. Fat16 has a 2GB limit... how do you format it at 4GB?

Hmm.. I'm not that much of a software person, but FAT16 uses 16-bit pointers to the clusters. Cluster size is limited to 64K on FAT 16 (does it have to do with 16 bit addressing?). That's 65536 clusters of 65536 bytes. If I punch that into a calculator, that's 4GB. Did I miss anything? Is the cluster size limited to 32K?

Jens Schönfeld

Quote:

The latest version even has a CF (Compact Flash) slot for those who want silent mass storage

You're forgetting that IDE64 has it's own filesystem that is not compatible with any PC. If you want to use the CF card to transfer data from a PC to the C64, you will need special software that is - AFAIK - still not available. With MMC64, you copy all files and D64 images to the card, then put it back into the C64 and have all the fun without hassle, becasue MMC64 supports the FAT16 filesystem.

We haven't checked the compatibility with SuperCPU yet, but there's nothing that is incompatible by default. Communication is register-based (which is 1Mhz even on SuperCPU), and the browser is in a 0x8000 rom, which is also supposed to work properly on SCPU. We'll know more at or after the TUM party, because that's the first chance to test and adapt compatibility (Neither Oliver nor I have a Super CPU).

Jens Schönfeld

@Wiesel

I'm not sure, but the 2GB limit may be due to FAT16 using signed (i.e. positive and negative) integers instead of unsigned. If it is signed then your integer range would be from -2GB to +2GB, and since you can't have a minus address you are left with just the positive 2GB range being usable.

Kind regards,

Francis
--
Powered by u-A1-C and AmigaOS 4.0!

_________________

And here I'm sitting, waiting for the reversed Lyra interface .. *thumbroll* :)

/Björn

The limit to 32KB cluster size was due to the fact that an integer could not comprehend the value 65536. An integer ranged from zero to 65535. This flaw in most programs made the largest power-of-two to be 32768, the designed cluster maximum size in FAT16. In WindowsXP, this is "fixed" allowing 64KB clusters, but no older DOS software will see anything above the first 2GB, and errors could occur trying perform operations on data in such an environment.

Further, the FAT implemented on most digital media is even more basic and oft-flawed than that which was ever on a PC-Clone. I would suspect that 2GB is the limit without a gross alteration to the FAT spec.

Taken from the MS Resource Kit docs:

FAT16 and FAT32 volumes are limited to 4 GB and 32 GB respectively ... FAT16 volumes larger than 2 GB are not accessible from computers running MS-DOS, Windows 95, Windows 98, Windows Me, and many other operating systems. This limitation occurs because these operating systems do not support cluster sizes larger than 32 KB, which results in the 2 GB limit.... FAT16 supports a maximum of 65,524 clusters per volume.