A CF Card Question

[+Larry]

I thought that I was having a compact flash and SD card reliability problem -- I had two different cards and I could not write to either one past sector 9999 using my IDE+2 HD. But MyDos showed both to have the correct size of 20,000 256-byte sectors. The KMKDIAG program and FDISK2 both showed that all was well with the partitions on each card. ???

 

Then I tried another card and everything was again worked well. I set that card up for 20,000 sectors and that's what it showed when running VTOCFIX on it. Then I remembered something that both cards had in common -- both had been used previously with a Black Box. The difference is that the BB divides a 512-byte physical sector on the media into two 256-byte sectors. (Pretty sure that the original KMK-JZ interface also did this, but the IDE+2 just uses 1/2 or 1/4 sectors.)

 

Then I took the cards and erased them and set them up on a MyIDE, again for the 20,000 MyDos sectors. After this erase/partitioning, the cards worked again when partitioned and set up with the IDE+2.

 

So here is the question for someone who knows their in's and out's on HD media -- any idea what the BB partitioning likely did to the cards so that the IDE+2 could not read past the 10,000 sector end point of the previous BB partition? It seems like this has to be the explanation as to what happened, but I sure don't know why!

 

-Larry

[+Larry]

...and the answer to my grief ultimately was pretty simple -- a corrupted copy of MyDos 4.55-b3.

My "success" with using the MyIDE erase was that I then unknowingly used a different copy of MyDos.

 

Sorry about that!

 

-Larry