topic Re: USB attaching and detaching in firmware in LPC Microcontrollers

USB attaching and detaching in firmware

lpcware — Wed, 15 Jun 2016 19:01:10 GMT

Content originally posted in LPCWare by pra18 on Wed Jul 23 08:19:03 MST 2014
Hi All,

I am trying to figure out how to realise in firmware, the attaching and detaching of USB for lpc435x.

For instance in one of the earlier ARM9 I worked on, it was like Setting and Clearing via GPIO TEST_DP Pin for attaching and detaching of the USB.

Does the lpc435x have such a pin which can be SET/CLEAR to attach and detach the USB bus?

Thanks in advance,

Re: USB attaching and detaching in firmware

lpcware — Wed, 15 Jun 2016 19:01:11 GMT

Content originally posted in LPCWare by embd02161991 on Fri Aug 08 17:11:19 MST 2014
Hi,

The RS bit (Run/Stop) bit in the USB Command register (USBCMD) can be used for an attach/deattach event.Writing a 0 to this bit will cause a detach event.Writing a one to this bit will cause the device controller to enable a pull-up
on USB_DP and initiate an attach event.

Thanks,
NXP Technical Support