Host Interrupt Flag Status and Clear
Name:
INTFLAG
Offset:
0x1C
Reset:
0x0000
Access:
-
Bit15141312111098
DDISCDCONN
AccessR/WR/W
Reset00
Bit76543210
RAMACERUPRSMDNRSMWAKEUPRSTHSOF
AccessR/WR/WR/WR/WR/WR/W
Reset000000

Bit 9 – DDISC: Device Disconnection Interrupt Flag

Device Disconnection Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when the device has been removed from the USB Bus and will generate an interrupt if INTENCLR/SET.DDISC is one.

Writing a zero to this bit has no effect.

Writing a one to this bit clears the DDISC Interrupt Flag.

Bit 8 – DCONN: Device Connection Interrupt Flag

Device Connection Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when a new device has been connected to the USB BUS and will generate an interrupt if INTENCLR/SET.DCONN is one.

Writing a zero to this bit has no effect.

Writing a one to this bit clears the DCONN Interrupt Flag.

Bit 7 – RAMACER: RAM Access Interrupt Flag

RAM Access Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when a RAM access error occurs during an OUT stage and will generate an interrupt if INTENCLR/SET.RAMACER is one.

Writing a zero to this bit has no effect.

Bit 6 – UPRSM: Upstream Resume from the Device Interrupt Flag

Upstream Resume from the Device Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when the USB has received an Upstream Resume signal from the Device and will generate an interrupt if INTENCLR/SET.UPRSM is one.

Writing a zero to this bit has no effect.

Bit 5 – DNRSM: Down Resume Interrupt Flag

Down Resume Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when the USB has sent a Down Resume and will generate an interrupt if INTENCLR/SET.DRSM is one.

Writing a zero to this bit has no effect.

Bit 4 – WAKEUP: Wake Up Interrupt Flag

Wake Up Interrupt Flag

This flag is cleared by writing a one.

This flag is set when:

l The host controller is in suspend mode (SOFE is zero) and an upstream resume from the device is detected.

l The host controller is in suspend mode (SOFE is zero) and an device disconnection is detected.

l The host controller is in operational state (VBUSOK is one) and an device connection is detected.

In all cases it will generate an interrupt if INTENCLR/SET.WAKEUP is one.

Writing a zero to this bit has no effect.

Bit 3 – RST: Bus Reset Interrupt Flag

Bus Reset Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when a Bus “Reset” has been sent to the Device and will generate an interrupt if INTENCLR/SET.RST is one.

Writing a zero to this bit has no effect.

Bit 2 – HSOF: Host Start-of-Frame Interrupt Flag

Host Start-of-Frame Interrupt Flag

This flag is cleared by writing a one to the flag.

This flag is set when a USB “Host Start-of-Frame” in Full Speed/High Speed or a keep-alive in Low Speed has been sent (every 1 ms) and will generate an interrupt if INTENCLR/SET.HSOF is one.

The value of the FNUM register is updated.

Writing a zero to this bit has no effect.