Other Parts Discussed in Thread: TPS2052B, TM4C1294NCPDT
Hi all,
I am a bit confused. The SPMU365C_EK-TM4C1294XL_Users Guide says:
"2.1.3 USB Connectivity
The Connected LaunchPad is designed to be USB 2.0 ready. A TPS2052B load switch is connected to and controlled by the microcontroller USB peripheral, which manages power to the USB micro A/B connector when functioning in a USB host. When functioning as a USB device, the entire Connected LaunchPad can be powered directly from the USB micro A/B connector. Use JP1 to select the desired power source. USB 2.0 functionality is provided and supported directly out of the box with the target USB micro A/B connector. High-speed USB 3.0 functionality can be enabled by adding an external USB PHY. The USB external PHY control and data signals are provided on the breadboard expansion header X11."
But the SPMS386C_TM4C1294NCPDT_Microcontroller_Datasheet says:
"The TM4C1294NCPDT USB module has the following features:
...
USB 2.0 high-speed (480 Mbps) operation with the integrated ULPI interface communicating
with an external PHY
..."
I'm wondering which datasheet contains the correct information?
I set up a TIRTOS USB firmware together with the USBCDCD driver. On the host I run a small Qt console application to determine the average triptime of 64 byte dummy data blocks. The ping pong works fine but the traffic is very slow (~700kB/s).
The device descriptor for the Virtual COM Port contains "USB Spec 1.1" in the bcdUSB field (determined with USBlyzer). For me it seems, as if the SPMS386C_TM4C1294NCPDT_Microcontroller_Datasheet contains the correct information. USB 2.0 is only working with the ext. PHY.
Am I right? If yes, does it also work with a ext. PHY for USB 3.0? If not, what am I doing wrong not beeing able to establish a USB 2.0 connection?
Thanks for your answer(s).
Regards, Miguel