39.17.8 Host Interrupt Flag Status and Clear

Name: INTFLAG
Offset: 0x1C
Reset: 0x0000
Property: -

Bit 15141312111098 
       DDISCDCONN 
Access R/WR/W 
Reset 00 
Bit 76543210 
 RAMACERUPRSMDNRSMWAKEUPRSTHSOF   
Access R/WR/WR/WR/WR/WR/W 
Reset 000000 

Bit 9 – DDISC 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

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

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

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

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

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

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

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 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.