Table of Contents

DIY Xbox 360 PC wireless receiver with MSP430 control

Germany 15.06.2013

Abstract

Xbox 360 wireless controller can be used with PC when special adapter is used. Xbox 360 itself has a separate RF module that communicates with motherboard through USB interface. Additional interface is used to initialize module LEDs and start sync process. One can create adapter for a fraction of cost using only several elements.

Description

Required parts:

Pinout of the RF board from top:

inline-svg@projects:xbr

Board must be powered by 3v3 so I decided to use LDO. Furthermore to start pairing process specific serial command must be sent. I have used MSP430G2231 for this task. MCU need reset pull-up resistor and decoupling capacitor. Pins 1 and 8 are connected to RF board.

Pairing process starts few seconds after device is powered. No external button needed. 

#include <msp430.h> 
#include <stdbool.h>
 
#define DATA 1
#define CLOCK 8
 
#define DTA_INPUT P1DIR &= ~DATA;
#define DTA_OUTPUT P1DIR |= DATA;
 
#define DTA_HI P1OUT |= DATA;
#define DTA_LO P1OUT &= ~DATA;
 
volatile signed   short bit_counter	=0;
volatile unsigned short command		=0;
 
 //Port 1 interrupt service routine
#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void)
{
 P1IFG &= ~CLOCK;
 
 // are we sending or receiving?
 if (bit_counter>0)
 {
	 DTA_OUTPUT
	 if (command & (1<<(bit_counter-1)))
		 DTA_HI
	 else
		 DTA_LO
 }
 // stop bit!
 else if (bit_counter == 0)
 {
	 P1OUT |= DATA;
	 command=0;
 }
 else
 {
	 DTA_INPUT
	 if (P1IN&DATA)
		 command |= (1<<((11+bit_counter)));
	 else
		 command &= ~(1<<((11+bit_counter)));
 }
 
 bit_counter--;
}
 
inline void send(char s)
{
	DTA_OUTPUT
	command = s;
	bit_counter = 10;
	DTA_LO				// Send start bit
}
 
//------------------------------------------------------------------------------
 
int main(void)
{
    unsigned short delay=0;
 
    //
    // CLOCK
    //
    WDTCTL = WDTPW | WDTHOLD;		// Stop watchdog timer
    if (CALBC1_1MHZ==0xFF)		// If calibration constants erased
    {
      while(1);                     	// do not load, trap CPU!!
    }
    DCOCTL = 0;                     	// Select lowest DCOx and MODx settings
    BCSCTL1 = CALBC1_1MHZ;
    DCOCTL = CALDCO_1MHZ;
 
    //
    // Serial Interface
    //
    P1OUT |= DATA; 			// DTA HIGH
    P1DIR |= (1<<6);
    DTA_OUTPUT 				// DTA OUTPUT
 
    P1IES |= CLOCK;			// fires on falling edge~
    P1IFG &= ~CLOCK; 			// int cleared
    P1IE |= CLOCK; 			// int enabled
 
    //
    // Start
    //
    __enable_interrupt();
    __delay_cycles(2000000);
 
    send(132);				// LEDs active with power button on
    while(--delay);			// Delay for a while
    send(0x085);			// Start animation
    while(--delay);
    while(--delay);
    send(0x004);			// Start sync
 
    __delay_cycles(5000000);		// Give some extra time to finish cmd send
 
    __disable_interrupt();		// Turn off MCU
    _BIS_SR(LPM4_bits);
 
}

Notes

References