USB device identification in SPSDK

In SPSDK apps such as blhost and sdphost communicate with NXP devices connected to host PC using USB. Such a devices could be identified by:

• VID and PID

• Device Path

• Device Name

USB - VID & PID

NXP devices use those VIDs:

• 0d28

• 1fc9

• 15a2

Devices in SPSDK could be identified either by VID only or a combination of VID/PID.

VID only could be defined as hex or dec numbers. Hex number must be preceded by 0x or 0X. The number of characters after 0x is 1 - 4. Mixed upper & lower case letters is allowed, e.g. 0xaB12, 0XAB12, 0x1, 0x0001. The decimal number is restricted only to have 1 - 5 digits, e.g. 65535. It’s allowed to set the USB filter ID to the decimal number 99999, however, as the USB VID number is a four-byte hex number (max value is 65535), this will lead to zero results. Leading zeros are not allowed e.g. 0001.

VID/PID cloud be separated by ‘:’ or ‘,’. The same rules apply to the number format as in the VID case, except, that the string consists of two numbers separated by ‘:’ or ‘,’. It’s not allowed to mix hex and dec numbers, e.g. 0xab12:12345. Valid vid/pid strings: 0x12aB:0xabc, 1,99999.

VID, PID detection using nxpdevscan

USB - Device Path

Device Path holds the USB ID obtained during USB HID device search and allows to compare, whether the provided USB HID object is the one to be used.

Note

The device path varies between OSes such as Windows, Linux, and Mac.

USB - Device Path - Windows

Device Path is a string in following format HID\\VID_<HEX>&PID_<HEX>\\<instance_id>. The device path could be located in Device Manager or using nxpdevscan.

Device Path location using Device Manager or nxpdevscan

USB - Device Path - Linux

Device Path is a path in the following form: 0003:0002:00.

The first number represents the Bus, the second Device, and the third Interface. The Bus:Device number is unique and the Interface is not necessary.

The Bus:Device can be listed using lsusb command. The Interface can be observed using lsusb -t. lsusb returns the Bus and Device as a 3-digit number. For the device identification in SPSDK <Bus in dec>#<Device in dec>, e.g. 3#11 should be used.

Device Path location using nxpdevscan or lsusb

Note

For nxpdevscan to list and SPSDK to use connected devices, it is necessary to configure udev rules so the app can access them. For NXP VIDs see USB - VID & PID.

1. Create a file for example 50-nxp.rules containing following rules:

SUBSYSTEM=="usb", ATTRS{idVendor}=="0d28", MODE="0660"
SUBSYSTEM=="usb", ATTRS{idVendor}=="1fc9", MODE="0660"
SUBSYSTEM=="usb", ATTRS{idVendor}=="15a2", MODE="0660"

2. To install rules copy the file to /etc/udev/rules.d:

sudo cp 50-nxp.rules /etc/udev/rules.d
sudo udevadm control --reload-rules
sudo udevadm trigger

3. Plug your NXP device(s) and call nxpdevscan.

USB - Device Path - Mac

Device Path is defined in following form:

IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/XHC1@14/XHC1@14000000/HS01@14100000/SE Blank RT Family @14100000/IOUSBHostInterface@0/AppleUserUSBHostHIDDevice

Device Path could be found using the ioreg utility or using IO Hardware Registry Explorer tool. However, using the system report from About This MAC -> System Report -> USB a partial path can also be gathered. Using the name of the USB device from the USB Device Tree and appending the Location ID should work. The name can be SE Blank RT Family and the Location ID is in a form of <hex> / <dec>, e.g. 0x14200000 / 18. So the usb_id name should be SE Blank RT Family @14200000 and the filter should be able to identify the required device.

Device Path location using USB Device Tree or nxpdevscan

USB - Device Name

USB device could be identified in SPSDK by Device Name. Device name could be listed by nxpdevscan.

Device Name detection using nxpdevscan