/* DHT22 Humidity controller using MBPIC V2 (Using MBL as bootloader) 2 inputs to control the humidity setpoint ie up/down 1 output (relay) pulsed on 2s off 10s (adjustable via rs232 by me) hysteresis of control loop set for 1% either way (c)2016 Jannie Hamman All rights reserved V1.0 - 08/02/2016 - Ported program from 18F88 prototype */ #include <18F4520.h> #device ADC=10 #use delay(crystal=4000000) #use rs232(baud=9600,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=8,stream=PORT1) //IO defines #define dht pin_c3 //IO pin for DHT22 data #define lcd_bl pin_b0 //LCD Backlight output #define humup pin_a0 //Humidity SP up adjust input #define humdwn pin_a1 //Humidity SP down adjust input #define relay pin_a2 //Relay for misting solenoid output //Global defines int i,hh,hl,th,tl,cs,ccs,cnt; int16 rhd,temp,humsp,flag,spdh,spdl,jrhd,jtemp,jspdh,jspdl; #bit neg = flag.0 //Negative temp flag #bit err = flag.1 //Sensor error #bit cse = flag.2 //Check sum error #bit relp = flag.3 //Relay pulse #bit sps = flag.4 //SP status ie mist on 1 or off 0 //LCD functions #define lcd_db7 pin_b7 #define lcd_db6 pin_b6 #define lcd_db5 pin_b5 #define lcd_db4 pin_b4 #define lcd_e pin_b3 #define lcd_rw pin_b2 #define lcd_rs pin_b1 #define lcd_4i_2line 0x28 //2/4 line, 4 bit interface #define lcd_line1 0x80 //line 1 position 1 #define lcd_line2 0xc0 //line 2 position 1 #define lcd_cls 0x01 //clear display, go home, no shift #define lcd_home 0x02 //go home, noshift #define lcd_doff 0x08 //display off #define lcd_donnc 0x0c //display on, cursor off #define lcd_donb 0x0d //display on, cursor off, blink on #define lcd_doco 0x0e //display on, cursor on #define lcd_docb 0x0f //display on, cursor on, blink on #define lcd_sfdc 0x04 //decrement DD RAM address #define lcd_shdl 0x05 //shift display left #define lcd_sfic 0x06 //increment DD RAM address #define lcd_shdr 0x07 //shifts entire display right #define lcd_cleft 0x10 //decrement cursor #define lcd_cright 0x14 //increment cursor #define lcd_dleft 0x18 //shift whole display left #define lcd_dright 0x1c //shift whole display right #define lcd_cgb 0x40 //CG RAM base address #define lcd_ddb 0x80 //DD RAM base address int defchar1[8]={0x04,0x0e,0x15,0x15,0x04,0,0,0}; //Up arrow int defchar2[8]={0,0,0x04,0x04,0x15,0x0e,0x04,0}; //Down arrow int defchar3[8]={0x1b,0x1b,0,0x04,0,0x11,0x0e,0}; //Face int defchar4[8]={0x18,0x18,0x03,0x04,0x04,0x04,0x03,0}; //Degree C symbol int defchar5[8]={0x03,0x04,0x0B,0x14,0x0B,0x04,0x03,0}; //Mist onp int defchar6[8]={0,0,0x0A,0x04,0x0A,0,0,0}; //Mist off int defchar7[8]={0x02,0x04,0x0A,0x14,0x0A,0x04,0x02,0}; //Mist on int defchar8[8]={0x0e,0x10,0x10,0x1f,0x1b,0x1b,0x1f,0}; //open lock #define arrowup 8 //Arrow up char \0 is NULL!!!!! #define arrowdwn 1 //Arrow down char #define aface 2 //Face (that smile?) #define degsym 3 //Degree sign #define okchar 4 //OK char #define oneontwo 5 //1 on top of 2 char #define lockclose 6 //Closed padlock #define lockopen 7 //Opened padlock int lcd_ln; //line number of current character int lcd_data; //data to and from LCD #bit lcdd7=lcd_data.7 #bit lcdd6=lcd_data.6 #bit lcdd5=lcd_data.5 #bit lcdd4=lcd_data.4 #bit lcdd3=lcd_data.3 #bit lcdd2=lcd_data.2 #bit lcdd1=lcd_data.1 #bit lcdd0=lcd_data.0 #bit lcdbf=lcd_data.7 //Send a byte to the LCD module //rs=0=command rs=1=character rs=2=4bit command void lcd_send_byte(int rs, int data) { lcd_data=data; output_low(lcd_rs); delay_us(80); if(rs==1)output_high(lcd_rs); else output_low(lcd_rs); delay_us(3); output_low(lcd_rw); delay_us(3); output_low(lcd_e); output_bit(lcd_db7,lcdd7); output_bit(lcd_db6,lcdd6); output_bit(lcd_db5,lcdd5); output_bit(lcd_db4,lcdd4); delay_us(3); output_high(lcd_e); delay_us(4); output_low(lcd_e); output_bit(lcd_db7,lcdd3); output_bit(lcd_db6,lcdd2); output_bit(lcd_db5,lcdd1); output_bit(lcd_db4,lcdd0); delay_us(3); output_high(lcd_e); delay_us(4); output_low(lcd_e); } //Read a byte from the LCD module //Returns 0 if RW=0 (connected to ground) int lcd_read_byte(void){ lcd_data=0; output_high(lcd_rw); delay_us(1); output_high(lcd_e); delay_us(3); lcdd4 = input(lcd_db4); lcdd5 = input(lcd_db5); lcdd6 = input(lcd_db6); lcdd7 = input(lcd_db7); output_low(lcd_e); delay_us(3); output_high(lcd_e); delay_us(3); lcdd0 = input(lcd_db4); lcdd1 = input(lcd_db5); lcdd2 = input(lcd_db6); lcdd3 = input(lcd_db7); output_low(lcd_e); return(lcd_data); } //Initialize LCD module //!!! Must be executed before using the CLCD !!! void lcd_init(void){ output_low(lcd_rs); output_low(lcd_e); output_low(lcd_rw); delay_ms(16); lcd_send_byte(2,0x03); delay_ms(6); lcd_send_byte(2,0x03); delay_us(260); lcd_send_byte(2,0x03); delay_ms(260); lcd_send_byte(2,0x02); lcd_send_byte(0,lcd_4i_2line); lcd_send_byte(0,lcd_donnc); //display on, no cursor lcd_send_byte(0,lcd_sfic); //auto incr cursor lcd_send_byte(0,lcd_cls); //clear screen and go home delay_ms(6); } //Write user chars to CGRAM void lcd_send_user(){ int i; lcd_send_byte(0,0x40); //CGRAM start = user defined char 1 for(i=0;i<=7;i++){ lcd_send_byte(1,defchar1[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar2[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar3[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar4[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar5[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar6[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar7[i]);} for(i=0;i<=7;i++){ lcd_send_byte(1,defchar8[i]);} } //Define on-the-fly user character 0 //Cursor (row7) defaults to 0 //Used for animation void lcd_def_char(int r0,int r1,int r2,int r3,int r4,int r5,int r6){ lcd_send_byte(0,0x40); //CGRAM start lcd_send_byte(1,r0); lcd_send_byte(1,r1); lcd_send_byte(1,r2); lcd_send_byte(1,r3); lcd_send_byte(1,r4); lcd_send_byte(1,r5); lcd_send_byte(1,r6); lcd_send_byte(1,0); //Row 7 is for cursor } //Change display position for next character to be written //x=position in line y void lcd_goto_pos(int x, int y){ int pos; switch(y){ case 1:pos=lcd_line1; break; case 2:pos=lcd_line2; break; } pos+=(x-1); lcd_send_byte(0,lcd_ddb|pos); delay_ms(1); } //Finally, the routine to write to the display //Usage: lcd_putc('X') or lcd_putc("\fLine 1\nLine 2\nLine 3\nLine 4") void lcd_putc(int x){ switch(x) { case '\f':lcd_send_byte(0,lcd_cls); lcd_ln=1; delay_ms(3); break; case '\n':lcd_goto_pos(1,++lcd_ln); break; case '\b':lcd_send_byte(0,lcd_cleft); break; default:lcd_send_byte(1,x); break; } } //DHT-22 FUNCTIONS //Determine pulse logic based on length int datain(){ int rddata=0; for(i=0;i<=7;i++){ err=false; //no error if waiting <1ms set_timer1(0); //error check start and exit if longer while(!input(dht)&&!err); //wait for line to go high delay_us(30); //high<28us means bit is 0 if(input(dht)){ //if still high bit is 1 set_timer1(0); //make counter 0 err=false; //no error yet bit_set(rddata,7-i); //data is 1 while(input(dht)&&!err); //wait for line to go low } } return rddata; } //Init and read sensor void rd_dht(){ output_float(dht); //make the pin an input delay_ms(250); //wait a bit output_low(dht); //start init sequence delay_ms(25); //keep low for 25ms output_high(dht); delay_us(30); //keep high for 30us output_float(dht); //pin is now an input err=false; //no error if waiting <1ms set_timer1(0); //error check start and exit if longer while(!input(dht)&&!err); //wait for sensor to pull line high err=false; //no error if waiting <1ms set_timer1(0); //error check start and exit if longer while(input(dht)&&!err); //wait for sensor to pull line low //this is the start of the transmission //The next 40 transistion high times determines 0 or 1 and needs to be timed //Thus we need to read 5 bytes //Read HH hh=datain(); //Read HL hl=datain(); //Read TH th=datain(); //Read TL tl=datain(); //Read CS cs=datain(); //Calculate checksum and flag if incorrect ccs=(hh+hl+th+tl)&0xff; cse=false; if(cs!=ccs)cse=true; //Make relative humidity an int16. Need to divide by 10 to get genuine RHD rhd=make16(hh,hl); //Check if temperature is negative or not neg=false; if(bit_test(th,7)){ neg=true; bit_clear(th,7); } //Make temperature an int16. Need to divide by 10 still! temp=make16(th,tl); } //Display error screen void serr(void){ printf(lcd_putc,"\fHC-22 HUMID CNTR"); printf(lcd_putc,"\nSENSOR IN ERROR!"); } //Display ego screen void ego(void){ printf(lcd_putc,"\fHC-22 HUMID CNTR"); printf(lcd_putc,"\n(c)2016 J Hamman"); } //Display the startup screen void strt(void){ printf(lcd_putc,"\fRH: %% SP: %%"); printf(lcd_putc,"\nTmp: Mist "); lcd_goto_pos(10,2); lcd_putc(0x03); } #INT_TIMER0 void TIMER0_isr(void){ //1s overflow if(input(humup))humsp+=10; if(humsp>=990)humsp=990; if(input(humdwn))humsp-=10; if(humsp<=1)humsp=0; spdh=humsp/100; spdl=(humsp-(spdh*100))/10; if(sps){ if(cnt==0)relp=false; if(cnt==1)relp=true; if(cnt==4)relp=false; cnt++; if(cnt==10){ cnt=0; // if(!cse)strt(); } } if(relp)output_high(relay); else output_low(relay); if(cse){ lcd_goto_pos(4,1); printf(lcd_putc,"%03.1f",(float)(jrhd)/10.0); lcd_goto_pos(14,1); printf(lcd_putc,"%lu%lu",jspdh,jspdl); lcd_goto_pos(5,2); if(neg)lcd_putc("-");else lcd_putc("+"); printf(lcd_putc,"%02.1f",(float)(jtemp)/10.0); } else{ lcd_goto_pos(4,1); printf(lcd_putc,"%03.1f",(float)(rhd)/10.0); lcd_goto_pos(14,1); printf(lcd_putc,"%lu%lu",spdh,spdl); lcd_goto_pos(5,2); if(neg)lcd_putc("-");else lcd_putc("+"); printf(lcd_putc,"%02.1f",(float)(temp)/10.0); jrhd=rhd; jtemp=temp; jspdh=spdh; jspdl=spdl; } //now add output status symbols (user defined 5 & 6 & 7) lcd_goto_pos(16,2); if(!sps)lcd_putc(0x05); if(sps&&relp)lcd_putc(0x04);else lcd_putc(0x06); } #INT_TIMER1 void TIMER1_isr(void){ //65ms overflow if(!err)err=true; } void main() { setup_timer_0(RTCC_INTERNAL|RTCC_DIV_16); //1.0 s overflow setup_timer_1(T1_INTERNAL|T1_DIV_BY_1); //65.5 ms overflow lcd_init(); lcd_send_user(); delay_ms(1000); output_high(lcd_bl); humsp=750; //Default humidity set at 75% flag=0; cnt=0; spdh=spdl=0; ego(); delay_ms(5000); strt(); delay_ms(1000); enable_interrupts(INT_TIMER0); enable_interrupts(INT_TIMER1); enable_interrupts(GLOBAL); while(TRUE) { //Get the sensor readings every 1.5s and do sp calc rd_dht(); if(rhd>=(humsp+10)){sps=false;cnt=0;} if(rhd<=(humsp-10))sps=true; delay_ms(1500); } }