What are the minimum hardware (pin) lines required for host (USB1) [No OTG] on the 1778?

[lpcware]

Content originally posted in LPCWare by MikeSimmonds on Mon Sep 24 01:57:56 MST 2012
On our custom board, what are the minimum processor pins I need to connect to get a USB host port (USB1) I don't care about over current or power enable as I intend to connect 5V permanently to the type A connector's Vbus pin.

I'm only ever going to plug in a USB flash drive for firmware update.

The UM10470 appears to imply that USB1_PWRD must be configured. Is this the case (I don't want any OTG stuff). If needed, can I tie to 5V (or 3.3V?) Or can I just enable the built in pull up?

Does the cpu USB controller detect device physical insertion? (and give me an interrupt so that on receipt I go do an Enum to find out what the device is).

Or do I have to poll now and then and do speculative Enums until one suceeds. If this case applies, do I have to configure USB_PWRD? [because I'd really not want to have to move what is currently on that particular pin.]

[lpcware]

Content originally posted in LPCWare by Daniel Widyanto on Thu Sep 27 01:18:26 MST 2012
Hi Mike,

USB Host mode needs:
- USB D+ pin
- USD D- pin
- USB_UP_LED1 pin
- USB_PWRD1 pin
- nUSBCR1 pin
- nUSB_PPWR1 pin

I don't know whether you want to follow USB spec or not, because the USB host should detect overcurrent condition and able to turn off the bus (hence nUSBCR1 and USB_PWRD1 is configured to detect overcurrent and USB VBus). Otherwise, it seems like connecting USB_PWRD1 to permanent 5V source is ok.

Btw, the internal pull up resistor is not able to pull USB_PWRD1 to 5V. So, you will still need to pull USB_PWRD1 to 5V VBus source.

For software part, yes, the USB host will detect device connection, and raise interrupt. From USB host ISR, user should generate linked list to the data that will be sent to start the enumeration.

Regards,
-daniel