Hello everyone
I am working on LPC2468 usb host with mass storage class . I am using NXP usb hostlite example as a base. I converted this source code for FAT32 system. It,s working fine for KIGNSTON 8 GB, SANDISK 4 GB pendrive. But when i used Hp 8 GB pendrive , it works fine sometime or sometime not.when I debug through the software the value of HOST_RhscIntr is not changing to 1. What,s the reason behind it.
So you need to look closer at why it is not changing to 1!
Look at your two examples that do work, and compare what's happening with the one that doesn't work.
"What,s the reason behind it"
There is a bug (or bugs) in your software that you just happen to get away with for the KIGNSTON 8 GB, SANDISK 4 GB pendrives, but your luck runs out with the the HP drive.
This is the big difference between just trying something a couple of times and saying, "it works" - and fully testing it to ensure that it complies with all conditions and requirements!
Either the thumb drives are differently formatted and that trig some issue.
Or there is a difference between they have different power requirements.
Or they may have different timing requirements.
Step 1 is to debug. And the lovely thing is that you have a situation where different memories gives different results - that is very good, because then you can compare. If none of the memories had worked, you would have had a way harder problem to fight.
CAN BE THE BUG IN THUMB DRIVE. LIKE LOTS OF SD CARDS HAVE BAD TIMINGS AND STUFF.
And the lovely thing is that you have a situation where different memories gives different results - that is very good, because then you can compare. lucky you, this means that you can debug your way backwards to find the actual place where the difference originates.
Erik
DON'T SHOUT!
Even if it is a bug in the HP drive, you said yourself that the PC accommodates it!
Far more likely a bug in your firmware.
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