Example : I2C

I2C components of OSS-EC

In this section, we will use the OSS-EC I2C component ( TI HDC1080 ) as an example.

• Block diagram of I2C components and OSS-EC software ( fig.1 )
• Application state transition of I2C components ( fig.2)
• API ( fig.3 )
• Architecture of PCMP ( fig.4 )

Blue label characters are data related to components.
Red label characters are data related to application.
Green label characters are data related to the circuit.

res.sts == iPowerOn_Reset_Fin is Normal Fin of Power ON Reset.
res.sts == iSW_Reset_Fin is Normal Fin of Software Reset.
res.sts == iMeasurement_Fin is Normal Fin of Measurement.
cmd.cnf == iREG_conf_measu is configuration of non-heater measurement.
cmd.cnf == iREG_conf_heat is configuration of heater measurement.
HDC1080.temp < iTemp_low is low temperature.
HDC1080.temp > iTemp_low is high temperature.
res.ic_reg[iRes_pos_conf] && iBTST == 0 is high battery voltage.
res.ic_reg[iRes_pos_conf] && iBTST == 1 is low battery voltage.
HDC1080.diag == iError occurs when any of the following conditions are met.
1) res.sp_dia == iError Count iError_times times in a row. // SP layer error ?
2) res.cp_dia == iError Count iError_times times in a row. // CP layer error ?
3) res.mp_dia == iError Count iError_times times in a row. // MP layer error ?

Note : If Diag==iError still occurs after several times of Software Reset, please set a State such as Sleep.

Structure name	Type	Structure members	Data meaning
HDC1080	float	temp	Temperature [degree Celsius]
	float	humi	Humidity [%RH]
	unsigned short	diag	Diagnostic result
	unsigned short	manu_id	Manufacturer ID
	unsigned short	devi_id	Devide ID
	unsigned long long	seri_id	Serial ID
cmd	unsigned short	ic	IC model number of OSS-EC
	unsigned short	cmd	Command of OSS-EC
	reg_type*	cnf[iReg_cnf_num]	Configration register value of command
res	unsigned short	sts	PCMP status
	unsigned short	sp_dia	SP diagnostic result
	unsigned short	cp_dia	CP diagnostic result
	unsigned short	mp_dia	MP diagnostic result
	float	phy_val[iPhy_type_num]	Sensor physical value phy_val[0] temperature [degree Celsius] phy_val[1] humidity [%RH]
	reg_type*	ic_reg[iReg_num]	register value res.ic_reg[iRes_pos_temp] temperature res.ic_reg[iRes_pos_humi] humidity res.ic_reg[iRes_pos_conf] configuration res.ic_reg[iRes_pos_seri1] Serial ID first res.ic_reg[iRes_pos_seri2] Serial ID mid res.ic_reg[iRes_pos_seri3] Serial ID last res.ic_reg[iRes_pos_manu] Manufacturer ID res.ic_reg[iRes_pos_devi] Device ID

reg_type : unsigned short : HDC1080 register length 16bit