USB Serial Port Adapter and Other USB Problems on Mavericks (OSX 10.9)

I upgraded to Mavericks yesterday and I have to say it went smoothly, except for the Moschip-based 7720 USB to serial port adapter I use to debug AVR embedded projects.  It worked fine on Snow Leopard.

I also noticed several complaints for these kinds of devices (not just Moschip based devices) on Mavericks.  So, beware...

From my syslog, the following errors were noted:

       
Dec  2 06:51:03 charles-benedicts-macbook.local com.apple.kextd[12]: WARNING - Invalid signature -67062 0xFFFFFFFFFFFEFA0A for kext "/System/Library/Extensions/MCS7720Driver.kext"


Dec  2 06:51:03 charles-benedicts-macbook.local com.apple.kextd[12]: Can't load /System/Library/Extensions/MCS7720Driver.kext - no code for running kernel's architecture.


Dec  2 06:51:03 charles-benedicts-macbook.local com.apple.kextd[12]: Load com.MosChip.driver.MCS7720Driver failed; removing personalities from kernel.

I am not sure whether the "no code" error is because the signature was invalid or whether the driver must be recompiled for 10.9.

Further research yields the following:

       
charles-benedicts-macbook:Extensions chuck_benedict$ sudo kextutil -b kextload -t ./MCS7720Driver.kext
Notice: /System/Library/Extensions/MCS7720Driver.kext has debug properties set.
Diagnostics for /System/Library/Extensions/MCS7720Driver.kext:
Warnings: 
    Executable does not contain code for architecture: 
        x86_64


Code Signing Failure: not code signed
Warnings: 
    Executable does not contain code for architecture: 
        x86_64


WARNING - Invalid signature -67062 0xFFFFFFFFFFFEFA0A for kext "/System/Library/Extensions/MCS7720Driver.kext"


Can't load /System/Library/Extensions/MCS7720Driver.kext - no code for running kernel's architecture.

So I did what I usually do in these cases.  I booted up Linux on Virtualbox and the serial port adapter works fine.

Finally, I have a home-built USBasp programmer that I use for hobby micro-controller projects with Atmel chips.  I had this device plugged into a powered Belkin USB hub and under Snow Leopard, it worked fine.  Since upgrading to Mavericks, the only way I can get it to work is to plug it directly into my Macbook.  Hmph...I don't know why this is, yet.