Cutting Of Device - Fujitsu F2MC-16LX Hardware Manual

CHAPTER 14 USB Mini-HOST
14.5.11

Cutting of Device

Once both Mini-HOST pins D + and D- become "L", the disconnection timer starts, and
sets the CSTAT bit of the host state status register (HSTATE) to "0" when both pins
detect "L" for 2.5 µs or longer.
Cutting of Device
Regardless of Mini-Host mode and function mode, when both Mini-Host pins D+ and D- detect "L" for
2.5 µs or longer, it determines that the device is cut. Therefore, the CSTAT bit of the host state status
register (HSTATE) becomes "0", and the DIRQ bit of the host interrupt register (HIRQ) is set to "1". If the
DIRE bit of the host control register 0(HCNT0) is "1", an interrupt generates. To clear the interrupt, write
"0" to the DIRQ bit of the HIRQ.
When a reset is performed on the USB bus, it determines that the device is disconnected and sets the
CSTAT bit of the host state status register 0 (HSTATE) to "0", but the DIRQ bit of the host interrupt
register (HIRQ) does not become "1".
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