Quote Originally Posted by defragster View Post
Thanks for seeing through making it usable!

I am using the SanDisk Ultra - a 32GB micro SDHC card. Seems that is what PJRC.com noted as good on the SD related page - brand makes a difference - and some are 'misbranded' it seems at times. But one seems dead now - and I tossed another cheapo out sometime during T4 Beta as well? I have new ones of some brand - not sure these were new just ones I had around open with no current purpose from old phones or something. Other than that this was the stock example from current downloads. For HDD's and other testing I had played some with alternate buffer sizes - but this was fresh from github.

@BOBILLIER - okay - simple FLASH cards work okay. But nothing HDD or even SSD would work without being on a powered HUB - so I wondered. And working from hub requires that 'HUB' code as noted then it can chain USB to get to a device on a HUB 'transparently'.

TeensyThreads seems nice - I just looked at it for Teensy 4 and learned the loop() is just thread 0 - not sure if it is treated like all other threads. I left a question I didn't see an answer to about that - and I didn't get back to it after I looked a bit. I did suggest a perf 'cycles per thread' used tracker for debug that got put in - I hacked up a slightly diff implementation that made more sense to me but didn't see any reaction to that yet. Using that it looked like in the sample I wrote 10% of the T_4 was consumed in the thread switching - mainly because my threads did very little and then did a .yield() so the switch rate was extreme.

@wwatson - seems I asked a while back about async calls to move data? THough not sure that would help TeensyThreads taskswitch any better unless it was running with DMA?
@defragster

I updated MassStorageHost.cpp and MassStorageDriver.cpp. There were some missing returns in a couple of functions hat the compiler was warning about. And of course I will be testing everything again to make sure I did not mess things up

@wwatson - seems I asked a while back about async calls to move data? THough not sure that would help TeensyThreads taskswitch any better unless it was running with DMA?
I can honestly tell you that I have no idea how to do this
I know Paul I going to be working on USBHost so I probably will wait till then.