C8051F340/1/2/3/4/5/6/7

USB Register Definition 16.9. FRAMEL: USB0 Frame Number Low

R

R

R

R

R

R

R

R

 

 

 

Frame Number Low

 

 

 

Bit7

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

Bit0

Bits7-0: Frame Number Low

This register contains bits7-0 of the last received frame number.

Reset Value

00000000

USB Address:

0x0C

USB Register Definition 16.10. FRAMEH: USB0 Frame Number High

R

R

R

R

R

R

R

R

Reset Value

-

-

-

-

-

Frame Number High

00000000

Bit7

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

Bit0

USB Address:

0x0D

Bits7-3: Unused. Read = 0. Write = don’t care.

Bits2-0: Frame Number High Byte

This register contains bits10-8 of the last received frame number.

16.8. Interrupts

The read-only USB0 interrupt flags are located in the USB registers shown in USB Register Definition 16.11 through USB Register Definition 16.13. The associated interrupt enable bits are located in the USB registers shown in USB Register Definition 16.14 through USB Register Definition 16.16. A USB0 interrupt is generated when any of the USB interrupt flags is set to ‘1’. The USB0 interrupt is enabled via the EIE1 SFR (see Section “9.3. Interrupt Handler” on page 87).

Important Note: Reading a USB interrupt flag register resets all flags in that register to ‘0’.

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Silicon Laboratories C8051F347, C8051F346, C8051F341 USB Register Definition 16.9. Framel USB0 Frame Number Low, Interrupts