lpcware

modifying usbhidrom with own system clock setup

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by pproc on Fri Dec 10 03:04:14 MST 2010
I am using the built-in rom based usbhid driver on the lpc1343 for my application and so far functionality is OK. Now I would like to optimize the system clock for power consumption. 

I commented out the call to the rom based init_clk_pins() function in the usbhidrom example.  Replaced this with my code setting system clock to 12MHz and the usb clock using the usb pll to 48MHz, and initialized the usb io pins.

With just the modifications i have made so far, my application code runs fine, enumeration as HID works, the usb setreport function works, but the getreport function is never being called.

Since the usbhidrom driver uses CT32B1 internally - my question is, what do i need to do in my code to initialize CT32B1 given that I have modified the system clock to 12Mhz.

Is there anything else i am missing as well ?  

regards hari

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