• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 30 subscribers
  • Views 562 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CCS/TM4C1294NCPDT: TM4C1294 pin assignment for USB device application

Jeff zhang
Prodigy 150 points
Part Number: TM4C1294NCPDT
Other Parts Discussed in Thread: EK-TM4C1294XL

Tool/software: Code Composer Studio

Hi,

I have custom design board with TM4C1294NCPDT with USB device port. We are planning to use it as serial debug port. When I power on this board, the USB serial port doesn't show up on Windows (Win7). I suspect the USB pin assignment may has some problem. The example application of EK-TM4C1294XL initialized PB0-1/PD6/PL6-7 are used for USB. But in my code (ported from example code, USB_device_cserial) I just initialized PL6-7 because PB0-1 are used for other purpose. I notice that the datasheet of this device mentioned (on page 1769):

"... If the USB controller is used as either a dedicated Host or Device, the

DEVMOD field in the USB General-Purpose Control and Status (USBGPCS) register can
be used to connect the USB0VBUS and/or USB0ID inputs to fixed levels internally, freeing
the PB0 and PB1 pins for GPIO use. "

My question is, if I need PB0-1 for other purpose, how should I initial the USB with only using PL6-7? the VBUS and ID pins are no connected in my design.

thanks,