My customer--Fujian Landi want to use low speed USB device for K21, now USB can't work well. i tried the customer's problem, I pull up 1.5K resistor in D-, and run KSDK1.2.0 USB HID device example in TWR-K21D50M,PC can't recognize the device. I read the K21DN512 RM, and found RM only mention OTG supports FS device. K21DN512 can support LOW SPEED device? and How to run LOW SPEED USB examples? Thanks.