USB startup wait loop delays UHS2 Task() starting for a while
like 200-600ms and USB suspend loop blocks the Task() while power
saving like 15-17ms. These loops may cause keyboard enumeration
failure, perhaps. Not confirmed it yet though.
Startup wait loop is originally intended to start keyboard task loop and
after console output endpoint becomes available. But now that console
output is buffered when it is not available and you don't have to wait
for it to be ready. You can disable the startup wait loop by defining
NO_WAIT_FOR_USB_CONFIGURED in config.h
Suspend loop is used for power saving by making tasks stop while
USB bus is under suspend status. But this may cause problem on some
devices like converter that must keep doing its task to retain
communication with keyboard. The suspend loop can block its task for
around 15-17ms. You can disable the suspend loop by defining
NO_USB_SUSPEND_LOOP in config.h.
Device classes are registered to array of config driver pool and
tried in that order until proper class is found in configuration process.
If tried driver cannot handle device, bus reset is issued to the device.
Calling led_set() in ISR can cause the problem. With converter
especially, led_set() can take long time and USB can be stuck in the end.
USB-USB converter freezes occasionally when computer power up or reboot.
https://geekhack.org/index.php?topic=69169.msg2740179#msg2740179
This is also related to suspend/wakeup issue #386.
according to the code:
static uint8_t matrix[MATRIX_ROWS];
#define ROW(code) (code>>3)
#define COL(code) (code&0x07)
in converter/terminal_usb/matrix.c
ROW is decided by bits 7-4 of scancode
COL is decided by bits 2-0 of scancode
according to the code:
static uint8_t matrix[MATRIX_ROWS];
#define ROW(code) (code>>3)
#define COL(code) (code&0x07)
in converter/ps2_usb/matrix.c
ROW is decided by bits 7~4 of scancode
COL is decided by bits 2~0 of scancode
