NXP Semiconductors K32 L2A Series, Reference Manual, Page: 312 / 1379

'I',0,
'C',0,
'E',0
};
14.4.5.3 Endpoints
The HID peripheral uses 3 endpoints:
• Control (0)
• Interrupt IN (1)
• Interrupt OUT (2)
The Interrupt OUT endpoint is optional for HID class devices, but the Kinetis Bootloader
uses it as a pipe, where the firmware can NAK send requests from the USB host.
14.4.5.4 HID reports
There are 4 HID reports defined and used by the bootloader USB HID peripheral. The
report ID determines the direction and type of packet sent in the report; otherwise, the
contents of all reports are the same.
Report ID Packet Type Direction
1 Command OUT
2 Data OUT
3 Command IN
4 Data IN
For all reports, these properties apply:
Usage Min 1
Usage Max 1
Logical Min 0
Logical Max 255
Report Size 8
Report Count 34
Each report has a maximum size of 34 bytes. This is derived from the minimum
bootloader packet size of 32 bytes, plus a 2-byte report header that indicates the length (in
bytes) of the packet sent in the report.
Peripherals Supported
K32 L2A Reference Manual, Rev. 2, 01/2020
312 NXP Semiconductors