AN169

18

Rev. 2.3

if (INTVAL & DEV_CONFIGURED)

{

// Initialize all analog peripherals here. This interrupt

// tells the device that it can now use as much current as

// specified by the MaxPower descriptor.

Init();

// Note: example command, not part of the API

}

if (INTVAL & DEV_SUSPEND)

{

// Turn off all analog peripherals

Turn_Off_All();

// Note: example command, not part of the API

USB_Suspend();

// This function returns once resume

//

signalling is present.

// Turn all analog peripherals back on

Init();

// Note: example command, not part of the API

}

}

4.1.

USB_Clock_Start

Description:

Enables the internal oscillator, initializes the clock multiplier, and sets the USB clock to 48 MHz

for USB full speed operation. If the clock multiplier is already initialized, the initialization proce-

dure is skipped. This function should be called before calling USB_Init or accessing any vari-

ables located in the upper 1024 bytes of XRAM (USB clock domain). CLKSEL[1:0] is not affected

by this function. See "Appendix A—SFRs that Should Not be Modified After Calling USB_-

Clock_Start and USB_Init” for more details. See "Appendix C—Firmware Library Notes” for

instructions on how to use the external oscillator as the USB clock.

Supported Devices:

C8051F320/1/6/7, C8051F340/1/2/3/4/5/6/7/8/9/A/B/C/D,

C8051F380/1/2/3/4/5/6/7, C8051T320/1/2/3/6/7, C8051T620/1/2/3

Prototype:

void USB_Clock_Start (void)

Parameters:

None

Return Value:

None