OK, I am running CentOS 6 on my Laptop and Desktop, presently kernel version 2.6.32-696.20.1.el6.x86_64 (yes, a version or so out of date -- I'll probably do an update soon -- non-trivial since my Internet connection is via dialup). I recently bought a couple of Adafruit Arduino compatibles, a Flora and a Metro 328. Hooking up the Flora and the Metro to a Raspberry Pi running Raspbian (kernel 4.9.35-v7+), tells me that the Metro 328's USB uses a FTDI USB serial interface (ftdi_sio.ko) and the Flora uses the cdc_acm (cdc-acm.ko) USB serial interface. Both of these drivers are available with CentOS 6's kernel, but since Adafruit uses their own Vendor & Product IDs and my (old) kernel's ftdi_sio and cdc-acm drivers don't have Adafruit Vendor & Product IDs, the drivers don't automagically connect. The ftdi_sio has parameters for the Vendor & Product IDs, and specifing the product ID for the Metro 328 allows the driver to latch onto the Metro 328's USB connect and things work (I get a /dev/ttyUSB0 device). The cdc-acm does not have any parameters and I don't see any way to get it to connect. I am pretty sure all Adafruit did was change the programming of the USB chip to have their Vendor & Product IDs and the driver should work (the FTDI one does, once the Vendor & Product IDs are passed to it). My question: since the cdc-acm is not parameterized, I am guessing I need to get the kernel module source (from RH's kernel source RPM? Or maybe Elrepo has it?), hack in the Adafruit Vendor & Product IDs into its table of Vendor & Product IDs and recompile it. Is this correct? Also: is there some "trick" that allows me to create a kernel module that will work with kernel updates, without having to re-compile it after every kernel update? -- Robert Heller -- 978-544-6933 Deepwoods Software -- Custom Software Services http://www.deepsoft.com/ -- Linux Administration Services heller at deepsoft.com -- Webhosting Services