MSP430F6659: device's usb not enumerated in host

It is necessary to configure the clock in the USB_config/descriptors.h file, with the USB_XT_* symbols.

(There is not USBPLL_SETCLK_ symbol for 16.384 MHz; you have to find the correct UPMB/UPQB values yourself, if that is even possible.)

Hello,
Thanks for your reply,

please find below code from discriptor.h .

this code is according to 16Mhz which i have selected discriptor tool software selection.


// MCLK frequency of MCU, in Hz
// For running higher frequencies the Vcore voltage adjustment may required.
// Please refer to Data Sheet of the MSP430 device you use
#define USB_PLL_XT 2 // Defines which XT is used by the PLL (1=XT1, 2=XT2)
#define USB_XT_FREQ_VALUE 16.0 // Indicates the freq of the crystal on the oscillator indicated by USB_PLL_XT
#define USB_XT_FREQ USBPLL_SETCLK_16_0 // Indicates the freq of the crystal on the oscillator indicated by USB_PLL_XT
#define USB_DISABLE_XT_SUSPEND 1 // If non-zero, then USB_suspend() will disable the oscillator
// that is designated by USB_PLL_XT; if zero, USB_suspend won't
// affect the oscillator
#define USB_DMA_CHAN DMA_CHANNEL_1 // Set to 0xFF if no DMA channel will be used 0..7 for selected DMA channel


please give me hardware connection diagram so that i can double check it.

As per my study when usb cable not connected with pc D+ line remain high and D- remain low initialy But in my harware it is not happening. In my case both line remain low. Is there any other changes required to make my device work ?


i am new in USB development so please explain detail.

What is the crystal frequency? 16 Mhz or 16.384 MHz?

Hello,

Thank you very much for your quick reply,

crystal is 16.384 but i have selected 16 mhz so i am going to replace it with 16 mhz in hardware because there is no selection for 16.384 Mhz in discriptor tool .

Unobtainium said:

crystal is 16.384 but i have selected 16 mhz so i am going to replace it with 16 mhz in hardware because there is no selection for 16.384 Mhz in discriptor tool .

USB spec defines the tolerance as +/- 0.25% (2500 ppm) for full-speed bus. It should work with your crystal, with manually inserted USBPLLDIV value.

Hello,

Thanks for your reply,

I can't find that where should i make above change in H0_SimpleSend example.

please mention file name in which i have to change for above setting.

one another issue i find is when i connect usb cable to my pc, MCU starts heating .

I can't getting that why MCU is heating as i verify hardware as per datasheet.

I have given 3.3V to mcu and use VBUS supply for USB module power. I have not taken any power out from VUSB and left it unconnected by simply placing 220nF capacitor between Vssb and VUSB (same for V18 and VUSB).

Unobtainium said:

I can't find that where should i make above change in H0_SimpleSend example.

please mention file name in which i have to change for above setting.

Find it by yourself. Just modify line USBPLLDIVB = something to USBPLLDIVB = 0x0625, or define your own constant and update code where it is needed.

#define USBPLL_SETCLK_16_384      0x0625  /* USB - PLL Set for 16.384 MHz input clock */

Hello
Thanks for your reply

i have found above line in discriptors.h and modified as you said above also i have found problem of heating of MCU as it is one of the hardware short . So both problem resolved

But still my device not enumerated in HOST pc

Sometimes HOST shows that "  A USB device has exceeded the power limit of its HUB port "  and " Unknown device "

There is one diode used in VBUS .which diode should i connect there. Is there any specific part number ?

please help me to troubleshoot the problem...

The Schottky diode prevents current from flowing from your device into the bus if the bus is powered off; it's needed only if you have a separate power supply.

The power limit error message says that your device uses too much current. Thus might be an error in your circuit (a short), or defective hardware.

Hello,
thanks for your reply,

the problem of power limit error solved and for once my device detected in Host pc and when i open demo app it become unknown device.
after that same problem of unknown device starts.

Hello,
thanks for your support,

My device got enumerated on HOST pc and start working.
But some time when i send data from HID Demo app it shows following error and device get disconnected.


TX-->11245678!
RX-->Error receiving buffer from device!
Disconnected from device


I have checked by placing break point at UNMI ISR but i think it is not due to any NMI reset interrupt because it will no go in UNMI ISR.