File content as of revision 0:7953b8ea1d53:

#include "mbed.h"

SPI my_spi(p5, p6, p7);
Serial pc(USBTX,USBRX);

#define TNF 0x02
#define TNE 0x01
#define RNE 0x04

/*** My method to write to FeRAM ***/
void spi_write (unsigned char data) {
    // First don't write to the FIFO buffer if it is full
    while (!(LPC_SSP1->SR & TNF))       // While TNF-Bit = 0 (FIFO full)...
        ;                               // Wait
    LPC_SSP1->DR = data;                // Write to FIFO buffer
}

/*** Write a byte to FeRAM ***/
void write_byte (int address, unsigned char data) {
    spi_write(0x02);                    // Send write command
    spi_write(address >> 16);           // Send top address byte to write to
    spi_write((address >> 8) & 0xFF);   // Send Middle address byte to write to
    spi_write(address & 0xFF);          // Send Bottom address byte to write to
    spi_write(data);                    // Send data to be write
    // Now I need to check that the FIFO transmit buffer is empty exiting the method
    while (!(LPC_SSP1->SR & TNE))       // While TNE-Bit = 0 (FIFO not empty)...
        ;                               // Wait
}

/*** Read a byte from FeRAM ***/
unsigned char read_byte (int address) {
    unsigned char my_val = 0;           // Variable to store the read data
    spi_write(0x03);                    // Send read command
    spi_write(address >> 16);           // Send top address byte to read from
    spi_write((address >> 8) & 0xFF);   // Send Middle address byte to read from
    spi_write(address & 0xFF);          // Send Bottom address byte to read from
    // Now the buffer is empty send out a dummy byte and read the buffer
    spi_write(0x00);                    // Send the dummy byte
    // Now I need to empty the FIFO receive buffer...
    while (LPC_SSP1->SR & RNE)          // While RNE-Bit = 1 (FIFO receive buffer not empty)...
        my_val = LPC_SSP1->DR;          // Read the byte in the buffer 
    return (my_val);                    // Return the last byte read
}

int main() {

    // Set up the SPI port...
    my_spi.frequency(32000000);         // 32MHz is the fastest mbed frequency supported by the FeRAM
    my_spi.format(8,3);                 // Set for mode 3
    LPC_PINCON->PINSEL0 |= 0x00002000;  // Set up SSEL1
    wait(0.001);                        // Must wait 1ms after power on before using FeRAM
    my_spi.write(0x06);                 // Send WREN command to write enable

    // Thought I would wait a bit to get a cleaner scope trace
    wait_us(2);

    // Write the byte...
    write_byte (100, 0x4C);
 
    // Thought I would wait a bit again
    wait_us(2);

    // read the byte and display on TeraTerm  
    int my_val = read_byte (100);
    pc.printf(" Value = 0x%X",my_val);
}