atmega128任意io口接入MAX5821 ADC芯片实现

//ARMADEUS+i2csw(avrlib)

void i2cInit(void)
{
	sbi( SDADDR, SDA);			// set SDA as output
	sbi( SCLDDR, SCL);			// set SCL as output
	I2C_SDL_HI;					// set I/O state and pull-ups
	I2C_SCL_HI;					// set I/O state and pull-ups

    extended_command powerCommand = { 0, 0, 0, 0 };


	powerCommand.powerMode = POWER_UP;
	powerCommand.command = MAX5821_EXTENDED_COMMAND_MODE;
	powerCommand.ctrlA = POWER_CTRL_SELECTED;
	powerCommand.ctrlB = POWER_CTRL_SELECTED;

	BUILD_EXTENDED_COMMAND(powerCommand, i2cdat);
	i2cSend(MAX5821L_IC_SLAVE_ADDRESS_VDD * 2, i2cdat[0], 1, &i2cdat[1]);
}


void ouputDAC()
{
	data_command setOutputCommand = { 0, 0, 0 };
	unsigned short val;
	float valf;

	valf = sysStat.oilval * 1024 / 200;
	if (valf >= 1023)
		valf = 1023;
	if (sysStat.statue == 0)
		val = valf;
	else val = 0;

	setOutputCommand.Sbits = 0;
	setOutputCommand.command = 0;
	setOutputCommand.data = val;
	BUILD_DATA_COMMAND(setOutputCommand, i2cdat);
	i2cSend(MAX5821L_IC_SLAVE_ADDRESS_VDD * 2, i2cdat[0], 1, &i2cdat[1]);
}