Dangerous Prototypes Open Source Hardware

//00001001 xxxxxxxx
case 9: //extended AUX command
		UART1TX(1); //confirm that the command is known
		//inByte - used as extended commmand
		//fr - used as result
		while(U1STAbits.URXDA == 0);//wait for subcommand byte
		inByte=U1RXREG; //get byte
		//0x00 - AUX/CS low
		//0x01 - AUX/CS high
		//0x02 - AUX/CS HiZ
		//0x03 - AUX read
		//0x10 - use AUX
		//0x20 - use CS
		
		
		fr=1;
		switch( inByte ) {
			case 0x00:
				bpAuxLow(0);
				break;
			case 0x01:
				bpAuxHigh(0);
				break;
			case 0x02:
				bpAuxHiZ(0);
				break;
			case 0x03:
				fr = bpAuxRead();
				break;
			case 0x10:
				modeConfig.altAUX = 0;
				break;
			case 0x20:
				modeConfig.altAUX = 1;
				break;
			default:
				fw = 0;
				break;
		}
		UART1TX(fr);//result
		break;

void bpAuxHigh(void){

#ifndef BUSPIRATEV4
	if(modeConfig.altAUX==0)
	{	BP_AUX_DIR=0;//aux output
		BP_AUX=1;//aux high
	}
	else
	{	BP_CS_DIR=0;//aux input
		BP_CS=1;//aux high
	}
#endif

	//AUX pin, high/low only
	if(inByte&0b10){
		BP_AUX_DIR=0;//aux output
		BP_AUX=1;//aux high
	}else{
		BP_AUX_DIR=0;//aux output
		BP_AUX=0;//aux low
	}

	//CS pin, follows HiZ setting
	if(inByte&0b1){
		if(modeConfig.HiZ==1){
			IODIR|=CS; //CS iput in open drain mode
		}else{	
			IOLAT|=CS; //CS high
			IODIR&=(~CS); //CS output
		}
	}else{
		IOLAT&=(~CS); //BP_CS=0;
		IODIR&=(~CS); //CS output
	}

HiZ>m
1. HiZ
2. 1-WIRE
3. UART
4. I2C
5. SPI
6. 2WIRE
7. 3WIRE
8. LCD
9. DIO
x. exit(without change)

(1)>4
Set speed:
 1. ~5KHz
 2. ~50KHz
 3. ~100KHz
 4. ~400KHz

(1)>1
Ready
I2C>W   
Power supplies ON
I2C>P
Pull-up resistors ON
I2C>g
1KHz-4,000KHz PWM
Frequency in KHz 
(50)>32
Duty cycle in % 
(50)>50
PWM active
I2C>C
a/A/@ controls CS pin
I2C>A %:2 [0xEE 0xFF 0xF0] %:50 [0xEE 0xFD[0xEF r:2] a
AUX HIGH
DELAY 2ms
I2C START BIT
WRITE: 0xEE ACK 
WRITE: 0xFF ACK 
WRITE: 0xF0 ACK 
I2C STOP BIT
DELAY 50ms
I2C START BIT
WRITE: 0xEE ACK 
WRITE: 0xFD ACK 
I2C START BIT
WRITE: 0xEF ACK 
READ: 0xB4  ACK 0xAD 
NACK
I2C STOP BIT
AUX LOW
I2C>

	//01001101 -- XCLR/CS high, keep VREG and PullUps
	
	if( BB_simpleCMD(fd, 0x4D, 1, "1") ) {
		return -1;
	}

	... //other I2C commands


	//01001100 -- XCLR/CS low, keep VREG, PullUps
	if( BB_simpleCMD(fd, 0x4C, 1, "1") ) {
		return -1;
	}