I am using TM4C1290NCPDT controller.
I am trying to configure USB as virtual serial port. Below is my USB configuration function.
void USB_Configuration(void) { uint32_t ui32PLLRate; ui32PLLRate = 480000000; ROM_GPIOPinTypeUSBAnalog(GPIO_PORTB_BASE, GPIO_PIN_0 | GPIO_PIN_1); ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_USB0); // // Initialize the transmit and receive buffers. // USBBufferInit(&g_sTxBuffer); USBBufferInit(&g_sRxBuffer); // // Set the USB stack mode to Device mode with VBUS monitoring. // USBStackModeSet(0, eUSBModeDevice, 0); // // Tell the USB library the CPU clock and the PLL frequency. This is a // new requirement for TM4C129 devices. // USBDCDFeatureSet(0, USBLIB_FEATURE_CPUCLK, &ui32SysClock); USBDCDFeatureSet(0, USBLIB_FEATURE_USBPLL, &ui32PLLRate); // // Pass our device information to the USB library and place the device // on the bus. // USBDCDCInit(0, (tUSBDCDCDevice *)&g_sCDCDevice); }
I copied usb_serial_struct.c & usb_serial_struct.h files from usb_device_serial example code.
And also i put USB0DeviceIntHandler() in startup.ccs file.
In my hardware i directly connected VBUS, D+,D-, & GND to USB connector.
But when i connect my device to PC using USB cable. The PC is unable to detect COM Port. There isn't any notification like unknown device or driver error when i connect or disconnect the usb cable.
So what's wrong in my code/hardware?