usb_selftest_hid Directory Reference

Directory dependency graph for usb_selftest_hid:

Directories
	inc
	src

Detailed Description

The interrupt-transfer member of the USB self-loop matrix: the device streams input reports on its interrupt-IN endpoint and the host reads and byte-checks them, through a real HID class. The two USB ports are cabled to each other and one image runs both stacks – USBFS (J11) is a ThreadX + USBX HID class with a vendor 8-byte input report, USBHS (J7) a self-contained polled host on the first-party ra8_usb_host_* primitives. No OS HID driver is involved.

Each report carries a rolling sequence byte plus a fixed pattern, so the host sees not just correct bodies but fresh ones rather than one stale buffer. The report is well under the 64-byte endpoint MPS, so it arrives as a single short packet; the host SIE drives the interrupt endpoint as a receive pipe, issuing IN tokens on demand, which is all a polled report read needs.

The device worker yields a tick between queue attempts so the lower-priority host thread can drain the report queue – both live on one CPU.

usb_host_keyboard covers the boot-keyboard descriptor and keycode decode instead. The s_dbg_* globals publish phase, round count, the first mismatch and the last sequence number read, for a J-Link readout.

Pinout

FS device: P4_07 VBUS sense, P5_00 VBUSEN GPIO LOW, P8_14/P8_15 data (PSEL usb_fs). HS host: SW4-8 Host via the U15 expander, PD07 HIGH (U18 powers J7), P4_08 VBUS sense (PSEL usb_hs). Console: PD_02/PD_03 SCI8. The device advertises VID 0x1209 with a per-app PID; bench use only.