On Thursday, August 28, 2014 8:30:32 PM UTC-7, wrote:
On Thursday, August 28, 2014 5:46:05 PM UTC-7, Retting wrote:

OK,,,more mystery.....I found a 32 MB 9contact card (not MMC) that does work. So...not sure what the limit is base on ...contacts vs. memory size.....maybe both....



No, if it has 9 contacts and a write protect switch it is an SD card of some type. MultiMedia Cards (MMC) have the same outline, are noticeably thinner, only 7 contacts, and no write-protect switch

Meant to add:

The difference between the various types of SD cards is some register changes and disk format, the original SD (SDSC) standard cards use FAT16 format with 512 byte block allowing 1 GB total capacity. A later revision of SDSC allowed 1024 or 2048 byte blocks, extending capacity to 2GB and 4GB, not all iPAQs were updated to support these larger block sizes. SDHC uses FAT32 format allowing up to 32 GB, SDXC uses exFAT allowing up to 2 TB, HP never updated the firmware to allow these formats.