Why can't I find an IVT at offset 0x400 of the demo SD card that comes with the Vybrid Tower ?

[alanball]

I'm trying to work out why an SD card I build from scratch (following the Timesys Linux doc) will not boot (no output at all)

According to the Vybrid RM, there should be an IVT located at 0x400 when booting from SD, however the demo SD (which boots fine) does not have this if I examine it using a hex editor (this area is all 0)

Anyone know why /

Thanks

[billpringlemeir]

I am pretty sure that the SD cards have an MBR (or master boot record) like a typical PC hard drive which defines partition information.  The Timesys help pages tell to do 'dd bs=512 seek=2' to skip over the MBR when updating u-boot.  The HAB code or (SD card boot mode) must also skip this MBR.  So a raw dump of the SD card should have an IVT at 0x800 (or 2k).

[karina_valencia]

timesyssupport can you help with this case?