SD Vs SDHC

I just got a Dane-Elec 4GB SDHC card. I works fine in my IOGear USB Reader/Writer but not in my digital cameras.
The price was so good I could not resist $30. I had a IOGear USB SD Reader/writer so now I have a 4GB jump drive.
Which joins my 8GB SONY, 6GB WD
I also have 5 1GB and 2 2GB SD cards so I have all the memory I need for my cameras.
Just why does SDHC not work with some equipment?

well its a new standard

SD format officially stoped at 2gb, while some companies still make SD cards in larger size, they are not official, and not fully supported by all devices.

some equipment simply doesn’t know that it can go over 2gb. in some cases camera will work it with until the 2gb mark, won’t format. only the latest cameras support sdhc.

SDHC uses sector addressing
SD uses byte addressing

Thanks :bow: