UART1 using alternate pins on Stellaris Launchpad

Hello,

I've hit a wall trying to modify the UART_echo demo project to work using UART1 on pins PC4 and PC5. Using these pins with the code below I get no activity on PC5 and no response on PC4 (using logic analyzer and oscilloscope). When I use pins PB0 and PB1 as UART1 the demo works perfectly. I'm hoping I have missed a configuration somewhere, but checking the registers GPIO_PCTL and GPIO_AFSEL against the datasheet the configuration looks good. My code below is for trying to use PC4 & PC5. Below that is the change for making it work on PB0 & PB1. Everything else remains constant. UART1 seems to be a popular topic, but I haven't seen one with this problem. Can someone please show me what I am missing?

Thank you for your time. 

#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "driverlib/debug.h"
#include "driverlib/fpu.h"
#include "driverlib/gpio.h"
#include "driverlib/interrupt.h"
#include "driverlib/pin_map.h"
#include "driverlib/rom.h"
#include "driverlib/sysctl.h"
#include "driverlib/uart.h"

//*****************************************************************************
//
//! \addtogroup example_list
//! <h1>UART Echo (uart_echo)</h1>
//!
//! This example application utilizes the UART to echo text. The first UART
//! (connected to the USB debug virtual serial port on the evaluation board)
//! will be configured in 115,200 baud, 8-n-1 mode. All characters received on
//! the UART are transmitted back to the UART.
//
//*****************************************************************************

//*****************************************************************************
//
// The error routine that is called if the driver library encounters an error.
//
//*****************************************************************************
#ifdef DEBUG
void
__error__(char *pcFilename, unsigned long ulLine)
{
}
#endif

//*****************************************************************************
//
// The UART interrupt handler.
//
//*****************************************************************************
void
UARTIntHandler(void)
{
unsigned long ulStatus;

//
// Get the interrrupt status.
//
ulStatus = UARTIntStatus(UART1_BASE, true);

//
// Clear the asserted interrupts.
//
UARTIntClear(UART1_BASE, ulStatus);

//
// Loop while there are characters in the receive FIFO.
//
while(ROM_UARTCharsAvail(UART1_BASE))
{
//
// Read the next character from the UART and write it back to the UART.
//
ROM_UARTCharPutNonBlocking(UART1_BASE,
ROM_UARTCharGetNonBlocking(UART1_BASE));

//
// Blink the LED to show a character transfer is occuring.
//
GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_2, GPIO_PIN_2);

//
// Delay for 1 millisecond. Each SysCtlDelay is about 3 clocks.
//
SysCtlDelay(SysCtlClockGet() / (1000 * 3));

//
// Turn off the LED
//
GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_2, 0);

}
}

//*****************************************************************************
//
// Send a string to the UART.
//
//*****************************************************************************
void
UARTSend(const unsigned char *pucBuffer, unsigned long ulCount)
{
//
// Loop while there are more characters to send.
//
while(ulCount--)
{
//
// Write the next character to the UART.
//
ROM_UARTCharPutNonBlocking(UART1_BASE, *pucBuffer++);
}
}

//*****************************************************************************
//
// This example demonstrates how to send a string of data to the UART.
//
//*****************************************************************************
int
main(void)
{
//
// Enable lazy stacking for interrupt handlers. This allows floating-point
// instructions to be used within interrupt handlers, but at the expense of
// extra stack usage.
//
ROM_FPUEnable();
ROM_FPULazyStackingEnable();

//
// Set the clocking to run directly from the crystal.
//
ROM_SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |
SYSCTL_XTAL_16MHZ);

//
// Enable the GPIO port that is used for the on-board LED.
//
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);

//
// Enable the GPIO pins for the LED (PF2).
//
ROM_GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_2);

//
// Enable the peripherals used by this example.
//
SysCtlPeripheralDisable(SYSCTL_PERIPH_UART0);

//
// Enable Peripheral Clocks
//
SysCtlPeripheralEnable(SYSCTL_PERIPH_UART1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOC);

//
// Enable port PC4 for UART1 U1RX
//
GPIOPinTypeUART(GPIO_PORTC_BASE, GPIO_PIN_4);
GPIOPinConfigure(GPIO_PC4_U1RX);

//
// Enable port PC5 for UART1 U1TX
//
GPIOPinTypeUART(GPIO_PORTC_BASE, GPIO_PIN_5);
GPIOPinConfigure(GPIO_PC5_U1TX);
//
// Configure the UART for 115,200, 8-N-1 operation.
//
ROM_UARTConfigSetExpClk(UART1_BASE, ROM_SysCtlClockGet(), 115200,
(UART_CONFIG_WLEN_8 | UART_CONFIG_STOP_ONE |
UART_CONFIG_PAR_NONE));

//
// Enable the UART interrupt.
//
IntEnable(INT_UART1);
UARTIntDisable(UART1_BASE,UART_INT_TX);
UARTIntEnable(UART1_BASE, UART_INT_RX | UART_INT_RT);

//
// Enable processor interrupts.
//
IntMasterEnable();

//
// Prompt for text to be entered.
//
UARTSend((unsigned char *)"\033[2JEnter text: ", 16);

//
// Loop forever echoing data through the UART.
//
while(1)
{
}
}

//
// Enable Peripheral Clocks
//
SysCtlPeripheralEnable(SYSCTL_PERIPH_UART1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);

//
// Enable port PB0 for UART1 U1RX
//
GPIOPinConfigure(GPIO_PB0_U1RX);
GPIOPinTypeUART(GPIO_PORTB_BASE, GPIO_PIN_0);

//
// Enable port PB1 for UART1 U1TX
//
GPIOPinConfigure(GPIO_PB1_U1TX);
GPIOPinTypeUART(GPIO_PORTB_BASE, GPIO_PIN_1);