ACI Master Code

#include <hidef.h>          /* for EnableInterrupts macro */
#include "derivative.h"     /* include peripheral declarations */
#include "hcs08.h"            // This is our definition file!

//MC9S08QE8 pins
#define ORANGELED PTAD_PTAD0
#define WHITELED PTAD_PTAD1
#define RESET PTAD_PTAD2
#define REQN PTBD_PTBD5
#define RDYN PTAD_PTAD3

//Temporary bytes for storing SPI registers
char r_data = 0;
char t_data = 0;
char status = 0;

//Buffers for receiving and transmitting
char r_buffer[32] = "";
char t_buffer[32] = "";

//Crude Software Delay
void myDelayer(int cycles) // > 50ns per cycle
{
    int i;
    for(i = 0; i < cycles; i++)
    {
    }
}
//Reads from SPI registers
char readACIByte()
{
    status = SPIS;
    return SPID;
}
//Writes to SPI registers
void writeACIByte(char data)
{
    status = SPIS;
    SPID = data;
}

//Interrupt that is triggered by the SPI receive register being full
void interrupt VectorNumber_Vspi spi_receive_isr(void)
{
  ORANGELED = 1;            //toggles LED
  r_data = readACIByte();   //reads data register into memory
  ORANGELED = 0;
}

//sends t_buffer via SPI
void writeCycle()
{
    int i;

    while(RDYN == 0);       //requires RDYN to be high

    WHITELED = RDYN;

    REQN = 0;               //Sets REQN low

    while(RDYN == 1);       //waits for RDYN to be low

    for(i = 0; i < (t_buffer[0] + 1); i++)  //loops through length
    {
        writeACIByte(t_buffer[i]);          //writes byte to SPI Data register
        r_buffer[i] = r_data;               //stores received reply in r_buffer
    }

    REQN = 1;                               //sets REQN to be high

    while(RDYN == 0);                       //waits for RDYN to be high
}

//reads sent SPI bytes into r_buffer
void readCycle()
{
    int i;

    while(RDYN == 1);       //Requires RDYN to be low

    WHITELED = RDYN;

    REQN = 0;               //Sets REQN low

    writeACIByte(0x00);     //writes zeros to get first byte
    r_buffer[0] = r_data;   //stores received data in memory
    if(r_data == 0x00)      //if the debug byte is 0, check again
    {
        writeACIByte(0x00);
        r_buffer[0] = r_data;
    }

    writeACIByte(0x00);     //write a zero to receive the length byte
    r_buffer[1] = r_data;   //store length byte

    for(i = 0; i < r_buffer[1]; i++)    //loop according to length
    {
        writeACIByte(0x00);             //write zero
        r_buffer[i+2] = r_data;         //receive and store byte
    }

    REQN = 1;                           //set REQN high again

    while(RDYN == 0);                   //wait for RDYN to be high

}

void readWriteCycle()       //read/write cycle first reads, then writes
{
    readCycle();
    writeCycle();
}

//Boots up the MCU
void mcu_init(void)
{
      SOPT1 = bBKGDPE;

      //Set up bus clock = 20MHz
      ICSC1 = 0b00000000;
      ICSC2 = 0b00000000;
      ICSSC = 0b00000000;

      //Configures SPI as per data sheet
      SPIC1 = 0b11010111;
      SPIC2 = 0b00001000;
      SPIBR = 0b00010000;       //Sets up SPI clock to 2Mhz

      PTADD_PTADD0 = 1;     //ORANGE LED is out
      PTADD_PTADD1 = 1;     //WHITE LED is out
      PTADD_PTADD2 = 1;     //RESET is out
      PTBDD_PTBDD5 = 1;     //REQN is out
      PTADD_PTADD3 = 0;     //RDYN is in

      REQN = 1;             //starts with REQN being high
      RESET = 1;            //starts with RESET being high

      EnableInterrupts;     //enables interrupts
}

//Resets the BLE module
void ble_init(void)
{
    RESET = 0;          //sets RESET low
    myDelayer(4);       //waits ~200 ns
    RESET = 1;          //sets RESET high
    myDelayer(20000);   //waits ~100 us
}

void main(void)
{
    mcu_init();                 // Initialise the MCU
    ble_init();                 // Reset the BLE

    //fill the transmit buffer with test command
    t_buffer[0] = 0x02;
    t_buffer[1] = 0x01;
    t_buffer[2] = 0x02;

    readWriteCycle();

    //fill the transmit buffer with echo command
    t_buffer[0] = 0x04;
    t_buffer[1] = 0x02;
    t_buffer[2] = 0x47;
    t_buffer[3] = 0x48;
    t_buffer[4] = 0x49;

    readWriteCycle();

    readCycle();

      while(1)
      {
          WHITELED = 0;
          ORANGELED = 0;
      }
}