USB_FTOGGLE usage

[lpcware]

Content originally posted in LPCWare by mtburt on Thu Jun 07 22:04:49 MST 2012
Hello,

I'm starting a new design with the LPC1343 and using the USB device peripheral.  I'm trying to finish up the schematic and can't seem to find how the USB_FTOGGLE pin is intended to be used.  From the user manual it looks like it's an output that toggles on the USB 1ms start-of-frame signal.  But I don't understand if there is some external trigger on that event or some other action that should be performed.

I just want to verify that I'm safe ignoring this output in my design.

Thanks in advance,
-Matt

[lpcware]

Content originally posted in LPCWare by Tsuneo on Fri Jun 08 18:01:38 MST 2012
USB_FTOGGLE pin of LPC13xx is an output-only pin.
This pin is supposed for USB Audio application, to synchronize external components (S/PDIF transceiver, MP3 codec, etc.) to the bus timing.

Tsuneo

[lpcware]

Content originally posted in LPCWare by Ex-Zero on Thu Jun 07 22:31:39 MST 2012
Usually this pin is used (as input) to use MSC (USB Bootloader).

It's not needed (as output) for general USB function :)

---

Quote:

8.4.1 LQFP48 packages
Table 144. LPC1313/42/43 LQFP48 pin description table

PIO0_1/CLKOUT/CT32B0_MAT2/USB_FTOGGLE
4[3] yes I/O I; PU PIO0_1 — General purpose digital input/output pin. A LOW level on this pin during reset starts the ISP command handler or the USB device enumeration (USB on LPC1343 only, see description of PIO0_3).

---