LPC43xx - USB Device MSC Rom API - Device Memory size > 4GB

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by nsmith17044 on Wed Feb 24 08:00:46 MST 2016
I created this topic separately from my previous post as the question is clearer now.

Evaluating the LPC43xx LPCOpen project usbd_rom_msc_ram.  My eventual goal is to target MMC integration for cards larger than 4GB.  It seems the original documentation on the MSC ROM API uses USBD_MSC_INIT_PARAM_T : MemorySize which is 32bits.  This would limit the full support size to 4GB.  However, looking at the current header file USDB_MSCUSER.H in the LPC_CHIP_43XX LPCOpen library (V2_12), I see at the end of the structure   uint64_t  MemorySize64;   I assume this has been added so to support memory devices larger the 4GB.  However I have found no documentation to support this member nor an example that uses it.


Can anyone clarify if sizes larger then 4GB are supported?  Should the MemorySize parameter be defined as 0 and then set the MemorySize64 to the actual size?  Are there any other initialization required?