ELT SENSOR

USER Guide of U-ARTfor S-300L/S-300L-3V/ T-110L/T-110L-3V

Ver. 20160719A

38,400bpsBaud Rate

1 BitStop Bit

No ParityParity Bit

8 BitsNumber of Bits

⃝ U-ART Specification

noneFlow Control

6 byte CO2 density stringD1~D6

Carriage Return : 0x0DCR

ppm stringppm

Line feed : 0x0ALF

Space : 0x20SP

D6 D5 D4 D3 D2 D1 SP ‘P’ ‘P’ ‘M’ CR LF

⃝ U-ART Data Format

0≤VIL≤0.8, 2.0≤VIH≤ VDD, 0≤VOL≤0.4, 2.4≤VOH≤ VDD (Volt) for S-300/T-110 0≤VIL≤0.4, 2≤VIH≤VDD, 0≤VOL≤0.4, 2.4≤VOH≤VDD (Volt) for S-300-3V/T-110-3V

▶ TTL Level Voltage

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CMD01 MCDL(10min. Recalibration) Start Command (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 'M' 'C' 'D' 'L' 'S' 0x03

CMD03 Recalibration Value Deletion Command (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 'C' 'L' 'E' A' 'R' 0x03

⃝ MCDL Command Set

HOST SENSOR

CMD01: MCDL Start Command

Response String ("MCDL_START¥r¥n")

After 15/25sec, S-300L-3V/T-110L-3V save data to EEPROM within 10sec.

The result data saved toEEPROM within 10sec.

CMD03: Recalibration Value Deletion Command

Response String ("RECAL_CLEAR¥r¥n")

Wait 1min.after boot

The default data restored toEEPROM within 10sec.

⃝ MCDL Control Sequence

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CMD11 ACDL(Automatic Recalibration) Start Command (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 ‘A' 'C' 'D' 'L' 'S' 0x03

CMD12 ACDL(1Automatic Recalibration) End Command (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 ‘A' 'C' 'D' 'L' 'E' 0x03

CMD13 Recalibration Value Deletion Command (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 'C' 'L' 'E' A' 'R' 0x03

⃝ ACDL Command Set

HOST SENSOR

CMD11: ACDL Start Command

Response String (“ACDL_START¥r¥n")

CMD12: ACDL Stop Command

Response String (“ACDL_STOP¥r¥n")

After7days.

The result data saved toEEPROM within 10sec.

CMD13: Recalibration Value Deletion Command

Response String ("RECAL_CLEAR¥r¥n")

Wait 1min.after boot

The default data restored toEEPROM within 10sec.

⃝ ACDL Control Sequence

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⃝ ALARM Command Set HOST SENSOR

CMD05: Low Limit Value Setting Command of Alarm

Response String (“ALARM_LOW=B5_Bn¥r¥n")

⃝ ALARM Control Sequence

CMD05 Set the Low Limit Value of ALARM

Position B5-Bn Bn+1

Value

B0

0x02

B1 B2 B3 B4

'A' 'L' 'M' 'L' Low PPM(ex:"700") 0x03

CMD06 Set the High Limit Value of ALARM

Position B5-Bn Bn+1

Value

B0

0x02

B1 B2 B3 B4

'A' 'L' 'M' 'H' High PPM(ex:"1000") 0x03

CMD07 Set the Protection Time of ALARM

Position B5-Bn Bn+1

Value

B0

0x02

B1 B2 B3 B4

'A' 'L' 'M' 'P' Time(ex:"600") [sec] 0x03

Response : ex) "ALARM_LOW=700¥r¥n"

Response : ex) "ALARM_HIGH=1000¥r¥n"

Response : ex) "ALARM_PROTECT=120¥r¥n"

CMD08 Write the setting value

Position B6

Value

B0

0x02

B1 B2 B3 B4

'A' 'L' 'M' 'W' 0x03

B5

'R'

CMD09 Read the set value

Position B6

Value

B0

0x02

B1 B2 B3 B4

'A' 'L' 'M' 'R' 0x03

B5

'D'

Response : ex) "ALARM_WRITE¥r¥n"

Response : ex) "ALARM_PROTECT=120¥r¥n""ALARM_LOW=700¥r¥n"

"ALARM_HIGH=1000¥r¥n"

CMD06: High Limit Value Setting Command of Alarm

Response String (“ALARM_HIGH=B5_Bn¥r¥n")

CMD07: Protection Time Setting Command of Alarm

Response String (“ALARM_PROTECT=B5_Bn¥r¥n")

CMD08: Writing the Set Value Command of Alarm

Response String (“ALARM_WRITE¥r¥n")

CMD09: Reading the Set Value Command of Alarm

Response String (“ALARM_PROTECT=B5_Bn¥r¥n")

Response String (“ALARM_LOW=B5_Bn¥r¥n")

Response String (“ALARM_HIGH=B5_Bn¥r¥n")

* On finish of CMD05/06/07, Write Command (CMD08) should be sent to keep the changed set value for alarm by Power on.

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⃝ Sleep Mode Start Command

HOST SENSOR

Normal Mode

⃝ SLEEP/AWAKE Control Sequence

CMD21 Sleep Mode Start (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 'S' 'L' 'E' 'E' 'P' 0x03

CMD22 Wake-up Command , Ending the Sleep Mode) (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 'A' 'W' 'A' 'K' 'E' 0x03

CMD21: Start of Sleep Mode Command ” Response String ("SLEEP¥r¥n")

CMD22: Wake-up Command, Ending Sleep mode

Response String ("WAKE_UP¥r¥n")

CO2 Concentration Data-1

CO2 Concentration Data-2

CO2 Concentration Data-N

⃝ Wake-up Command

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⃝ Target PPM Start Command HOST SENSOR

⃝ TARGET PPM

CMD23 Target PPM Command (Host->Sensor)

Position B0 B1 B2 B3 B4 B5 B6

Value 0x02 'T' 'P' 'P' 'M' 0x20 1

CMD23: Start of Target Command ”

Response String ("TPPMr¥n")

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Target PPM Command (Host->Sensor)

B11 B12 B13 B14 B15 B16

0x20 0x20 4 0 0 0x03

B10

>

B9

0

B8

0

B7

0

ø예) Target PPM 1000 ppm -> 400 ppm

§ Total 17 bytes§ 'TPPM' + Current ppm + '>' + Target ppm § Current ppm : 5 Digit.§ Target ppm : 5 Digit.§ Target values reflects takes about more than 6 seconds after command

⃝ RecommendationsDirective use range for minimize error to effective sensor value§ PPM RANGE : 0 - 2000 ppm§ Target to up : 1000 ppm within differences, ex, 400 -> 1400(max)§ Target to down: 300 ppm within differences, ex 1000 -> 700(min)

ø Currently supported model§ S300 3V, T110 3V

Packet

Period of Sampling

Data

POWER MODE

3 or 5 seconds 3 or 5 seconds

Current

Normal Mode Normal ModeSleep Mode

Peak State

'Sleep-Command

‘Wake-upCommand

Data N-1 Data N+1Data N Data N

Sleep StateNormal State

Time

Lamp Turn On Lamp Turn On

⃝ Timing Diagram of Sleep

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B. Pseudo code of UART Parser

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Pseudo Code-1/3

//Circular Queue#define MAX_QUEUE_SIZE 20char RxQueue[MAX_QUEUE_SIZE];int QueWRPos=0;int QueRDPos=0;

UARTx_ISR(){

int iTmp;

//.....

iTmp=QueWRPos+1;if(iTmp>=MAX_QUEUE_SIZE){iTmp=0;}else{;}if(iTmp!=QueRDPos)

{//Non-OverflowRxQueue[QueWRPos]=RXDATA;QueWRPos=iTmp;}

else{;} //Overflow -> Discard data

//.....

}

void UARTx_Process(void);int RXParser(void);

void main(){

while(1){//.....UARTx_Process();//.....}

}

#define MAX_PACKET_SIZE 15char RxBuff[MAX_PACKET_SIZE];int RxWRPos=0;void UARTx_Process(void){

char cTmp;while(QueWRPos!=QueRDPos)

{//SerializationcTmp=RxQueue[QueRDPos];QueRDPos++;if(QueRDPos>=MAX_QUEUE_SIZE){QueRDPos=0;}else{;}

RxBuff[RxWRPos]=cTmp;RxWRPos++;

//0x0A=End of Packetif(cTmp==0x0A)

{RxParser();RxWRPos=0;return;}

//Discard data on overflowelse if(RxWRPos>=MAX_PACKET_SIZE)

{RxWRPos=0;}

else{;}

}//End of While}

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Pseudo Code-2/3

// Packet format : [D6][D5][D4][D3][D2][D1][SP]['p']['p']['m'][0x0D][0x0A]int RXParser(void){

int iPos,LP01;char *pSrcBuff;long RetPPM; //The data type is depend on MCU

if(RxWRPos<7){return(-1);}else{;} //Minimum packet : [D1][SP]['p']['p']['m'][0x0D][0x0A]iPos=RxWRPos-7;pSrcBuff=&RxBuff[iPos];if((pSrcBuff[1]!=0x20)||

(pSrcBuff[2]!='p')||(pSrcBuff[3]!='p')||(pSrcBuff[4]!='m')||(pSrcBuff[5]!=0x0D)||(pSrcBuff[6]!=0x0A)){return(-1);}else{;}

pSrcBuff[1]=0; //Insert the termination character in [SP]

//Search the first character of PPM stringpSrcBuff=NULL;for(LP01=0;LP01<=iPos;LP01++)

{if(RxBuff[LP01]!=0x20)

{pSrcBuff=&RxBuff[LP01];break;}else{;}

}

if(pSrcBuff==NULL){return(-1);}else{;}

RetPPM=atol(pSrcBuff); //or atoi(pSrcBuff)

return(0);

}

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Pseudo Code-3/3

Thanks for Reading

Contact : Judy Kim, Charlie Wang, TEL: +82-32-719-8055, sales@eltsensor.co.kr

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