;************************************************************************************ ; Software License Agreement ; ; The software supplied herewith by Microchip Technology Incorporated (the "Company") ; for its PICmicro(r) Microcontroller is intended and supplied to you, the Company's ; customer, for use solely and exclusively on Microchip PICmicro Microcontroller ; products. ; ; The software is owned by the Company and/or its supplier, and is protected under ; applicable copyright laws. All rights are reserved. Any use in violation of the ; foregoing restrictions may subject the user to criminal sanctions under applicable ; laws, as well as to civil liability for the breach of the terms and conditions of ; this license. ; ; THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION. NO WARRANTIES, WHETHER EXPRESS, ; IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF ; MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE ; COMPANY SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR ; CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER. ; ;************************************************************************************ ; ; Filename: Clock.asm ; Date: March 11,2005 ; File Version: 1.00 ; ; Company: Microchip Technology Inc. ; ;************************************************************************************ ; ; Files required: ; Clock.inc ; 16f917.lkr ; LCD.inc ; LCD.asm ; ; ;************************************************************************************ ; ; Notes: This project implements a real-time clock using the 32.768kHz crystal. ; The crystal gives a reliable time base compared to the internal RC ; oscillator on-board the PIC16F917. The RC oscillator may be off by ; +- 1%. The crystal in combination with some circuitry internal to the ; PIC microcontrontroller drives Timer 1 at a frequency of 32.768kHz. Bit ; 6 gives a 1/2 second time period. This is used as the basis for keeping ; time and blinking the decimal point at a 1/2 second rate. ; - SW2 is used to set the hours (note the "A" for indication AM) ; - SW3 is used to set minutes ; - SW4 toggles between displaying hours/minutes and seconds ; ; Connections: ; OSI (J4) to T1OSI (J13) ; OSO (J4) to T1OSO (J13) ; SW2 (J4) to RA3 (J13) ; SW3 (J4) to RA4 (J13) ; SW4 (J4) to RA5 (J13) ; ;************************************************************************************ #include ;********************************************************************** STARTUP code goto Initialize PORT1 code ;************************************************************************************ ; Initialize - Initialize CCP1, comparators, internal oscillator, I/O pins, ; analog pins, motor parameters, variables ; ;************************************************************************************ Initialize clrf STATUS ; bank 0 bsf STATUS,RP0 ; we'll set up the bank 1 Special Function Registers fist ; Configure I/O pins for project bsf TRISA,7 ; RA7 is an input bsf TRISA,6 ; RA6 is an input bsf TRISA,5 ; RA5 is an input bsf TRISA,4 ; RA4 is an input bsf TRISA,3 ; RA3 is an input ; Set internal oscillator frequency movlw b'01110000' ; 8Mhz movwf OSCCON ; Set TMR0 parameters movlw B'10000110' ;PORTB PULL-UP DISABLED movwf OPTION_REG ;TMR0 RATE 1:128 ; Turn off comparators movlw 0x07 movwf CMCON0 ; turn off comparators ; Turn off Analog clrf ANSEL bcf STATUS,RP0 ; go back to bank 0 ; Set up Timer 1 movlw b'00001011' ; Use external oscillator movwf T1CON ;************************************************************************************ ; Main - The main loop makes the time, displays the time, and responds to button ; presses from the user. ; ;************************************************************************************ Main call InitLCD ; Initialize LCD Special Function Registers clrf Second ; Display 12:00 on startup clrf Minute movlw .12 movwf Hour clrf TimeBaseMultiple ; This variable is keep track of the number of 1/2 second intervals clrf Flag clrf StateSW2 clrf StateSW3 clrf StateSW4 bsf TMR1H,6 ; Make sure the first time around the code displays something ; Main program loop Loop call ServiceSwitches ; Looks for button presses an whether or not a switch debounce routine is currently being executed btfss TMR1H,6 ; 1/2 second will be our timebase (when bit 6 is set 1/2 second has passed goto Loop bcf TMR1H,6 incf TimeBaseMultiple,f ; Keep track of 1/2 second intervals (bit 0 is 1 at 1 second intervals, bit 1 is 1 at 2 second intervals, etc.) ; Every 1/2second do this call BlinkDot ; toggle blink flag call DisplayTime ; Display either seconds or Hour and Minutes dempending on mode ; Every 1 second do this btfsc TimeBaseMultiple,0 goto EndLoop call MakeTime ; Constuct the time (increment seconds, minutes, hours appropiately) EndLoop goto Loop ;************************************************************************************ ; BlinkDot - Toggle the flag indicating whether the blinking dot is set or not. ; ;************************************************************************************ BlinkDot movlw 0x20 ; Toggle Blink Flag xorwf Flag,f return ;************************************************************************************ ; DisplayTime - Display the time based on the state of the "DisplayMode" flag. ; ;************************************************************************************ DisplayTime call InitLCD ; Clear display momentarily btfsc Flag,Blink ; If the Blink flag is set then display the dot call Display3DP btfsc Flag,DisplayMode ; Display either seconds or Hour and Minutes depending on mode call DisplaySeconds btfss Flag,DisplayMode call DisplayHourAndMinutes return ;************************************************************************************ ; DisplaySeconds - Convert Seconds to Binary Coded Decimal (BCD) and then display. ; ;************************************************************************************ DisplaySeconds movf Second,w call ConvertToBCD movwf SecondBCD movf SecondBCD,w andlw 0x0F call DisplayDigit1 swapf SecondBCD,w andlw 0x0F call DisplayDigit2 return ;************************************************************************************ ; DisplayHourAndMinutes - Convert Hours and Minutes to BCD and display. ; ;************************************************************************************ DisplayHourAndMinutes movf Minute,w call ConvertToBCD movwf MinuteBCD movf Hour,w call ConvertToBCD movwf HourBCD movf MinuteBCD,w andlw 0x0F call DisplayDigit1 swapf MinuteBCD,w andlw 0x0F call DisplayDigit2 movf HourBCD,w andlw 0x0F call DisplayDigit3 swapf HourBCD,w andlw 0x0F call DisplayDigit4 btfss Flag,AMorPM call DisplayA return ;************************************************************************************ ; MakeTime - Construct seconds, minutes, and hours every 1 second. ; ;************************************************************************************ MakeTime call IncrementSecond btfsc STATUS,Z ; If seconds overflows (59 to 0) then the zero flag is set call IncrementMinute btfsc STATUS,Z ; If minutes overflows (59 to 0) then the zero flag is set call IncrementHour return ;************************************************************************************ ; IncrementSecond - Increment seconds ; Output - Zero flag set if Second rolls over from 59 to 0 ; ;************************************************************************************ IncrementSecond incf Second,f movf Second,w xorlw .60 btfsc STATUS,Z clrf Second return ;************************************************************************************ ; IncrementMinute - Increment minutes ; Output - Zero flag set if Minute rolls over from 59 to 0 ; ;************************************************************************************ IncrementMinute incf Minute,f movf Minute,w xorlw .60 btfsc STATUS,Z clrf Minute return ;************************************************************************************ ; IncrementHour - Increment the hour. Toggle the "ToggleAMorPM" flag when hour ; rolls over from 12 to 1. ; ;************************************************************************************ IncrementHour incf Hour,f movf Hour,w ToggleAMorPM xorlw .12 btfss STATUS,Z goto Next movlw 0x10 xorwf Flag,f ; Change from AM to PM or vice versa Next movf Hour,w xorlw .13 btfss STATUS,Z goto EndMakeHour movlw 1 movwf Hour goto EndMakeHour EndMakeHour return ;************************************************************************************ ; ConvertToBCD - Convert a decimal number to Binary Coded Decimal (BCD). This ; function only works for values less than 100. ; ;************************************************************************************ ConvertToBCD movwf Temp incf Temp,f clrf BCDValue ConvertLoop decf Temp,f btfsc STATUS,Z goto EndConvertToBCD incf BCDValue,f movf BCDValue,w andlw 0x0F xorlw 0x0A btfss STATUS,Z goto ConvertLoop movlw 0x06 addwf BCDValue,f goto ConvertLoop EndConvertToBCD movf BCDValue,w return ;************************************************************************************ ; ServiceSwitches - Checks for pressed switches. It a switch is pressed a flag ; is set to indicate the switch has been pressed. This initiates a routine that ; debounces the switch and also determines the functionality of the switch. The ; flag is only cleared when the routine is over ; ;************************************************************************************ ServiceSwitches btfss SW2 ; If SW2 is pressed set a flag to begin debounce routine bsf Flag,ServiceSW2 btfss SW3 ; If SW3 is pressed set a flag to begin debounce routine bsf Flag,ServiceSW3 btfss SW4 ; If SW4 is pressed set a flag to begin debounce routine bsf Flag,ServiceSW4 btfsc Flag,ServiceSW2 ; Set the hour if SW2 is pressed call SetHour btfsc Flag,ServiceSW3 ; Set the minute if SW3 is pressed call SetMinute btfsc Flag,ServiceSW4 ; Toggle between display modes when SW4 is pressed call ChangeDisplay EndServiceSwitches return ;************************************************************************************ ; SetHour - Implements a state machine that debounces SW2 and also determines whether ; or not SW2 was pressed momentarily or whether it is being held down. If pressed ; momentarily then increment hour only once. If pressed and held, then increment ; the hour at a rate of one hour per 1/4 second. ; ;************************************************************************************ SetHour movlw high SW2StateTable movwf PCLATH movf StateSW2,w andlw 0x07 ; mask off state pointer addlw low SW2StateTable btfsc STATUS,C incf PCLATH,f movwf PCL SW2StateTable goto SW2State0 goto SW2State1 goto SW2State2 goto SW2State3 goto SW2State4 goto SW2State5 nop clrf StateSW2 bcf Flag,ServiceSW2 return SW2State0 ; Check for button press clrf TMR0 bcf INTCON,T0IF incf StateSW2,f return SW2State1 btfsc SW2 ; If button is released before timeout then exit state machine goto ExitStateMachine btfss INTCON,T0IF ; Has 16ms passed? goto EndSW2State1 call IncrementHour ; Yes then Increment the Hour and display it call DisplayTime clrf Counter ; Prepare for next time sequence where we wait to see how long clrf TMR0 ; the button is pushed bcf INTCON,T0IF incf StateSW2,f goto EndSW2State1 ExitStateMachine bcf Flag,ServiceSW2 clrf StateSW2 EndSW2State1 return SW2State2 btfsc SW2 goto SW2Unpressed ; Button pressed less than 1/2 second btfss INTCON,T0IF goto EndSW2State2 bcf INTCON,T0IF incf Counter,f btfsc Counter,5 ; if 1/2 second has passed then proceed to next state incf StateSW2,f goto EndSW2State2 SW2Unpressed movlw 2 addwf StateSW2,f EndSW2State2 return SW2State3 ; Button pressed a long time, increment hour faster btfsc SW2 incf StateSW2,f btfss INTCON,T0IF goto EndSW2State3 bcf INTCON,T0IF incf Counter,f btfss Counter,4 ; if 1/4 second has passed then increment hour goto EndSW2State3 bcf Counter,4 call IncrementHour call DisplayTime EndSW2State3 return SW2State4 btfss SW2 ; Wait for button release goto EndSW2State4 clrf TMR0 bcf INTCON,T0IF incf StateSW2,f EndSW2State4 return SW2State5 btfss SW2 goto BackToSW2State1 btfss INTCON,T0IF goto EndSW2State5 bcf Flag,ServiceSW2 clrf StateSW2 goto EndSW2State5 BackToSW2State1 decf StateSW2,f EndSW2State5 return ;************************************************************************************ ; SetMinute - Implements a state machine that debounces SW3 and also determines whether ; or not SW3 was pressed momentarily or whether it is being held down. If pressed ; momentarily then increment minute only once. If pressed and held, then increment ; the minute at a rate of one minute per 1/8 second. ; ;************************************************************************************ SetMinute movlw high SW3StateTable movwf PCLATH movf StateSW3,w andlw 0x07 ; mask off state pointer addlw low SW3StateTable btfsc STATUS,C incf PCLATH,f movwf PCL SW3StateTable goto SW3State0 goto SW3State1 goto SW3State2 goto SW3State3 goto SW3State4 goto SW3State5 nop clrf StateSW3 bcf Flag,ServiceSW3 return SW3State0 ; Check for button press clrf TMR0 bcf INTCON,T0IF incf StateSW3,f return SW3State1 btfsc SW3 ; If button is released before timeout then exit state machine goto ExitSW3StateMachine btfss INTCON,T0IF ; Has 16ms passed? goto EndSW3State1 call IncrementMinute ; Yes then Increment the Minute and display it call DisplayTime clrf Counter ; Prepare for next time sequence where we wait to see how long clrf TMR0 ; the button is pushed bcf INTCON,T0IF incf StateSW3,f goto EndSW3State1 ExitSW3StateMachine bcf Flag,ServiceSW3 clrf StateSW3 EndSW3State1 return SW3State2 btfsc SW3 goto SW3Unpressed ; Button pressed less than 1/2 second btfss INTCON,T0IF goto EndSW3State2 bcf INTCON,T0IF incf Counter,f btfsc Counter,5 ; if 1/2 second has passed then proceed to next state incf StateSW3,f goto EndSW3State2 SW3Unpressed movlw 2 addwf StateSW3,f EndSW3State2 return SW3State3 ; Button pressed a long time, increment hour faster btfsc SW3 incf StateSW3,f btfss INTCON,T0IF goto EndSW3State3 bcf INTCON,T0IF incf Counter,f btfss Counter,3 ; if 1/8 second has passed then increment hour goto EndSW3State3 bcf Counter,3 call IncrementMinute call DisplayTime EndSW3State3 return SW3State4 btfss SW3 ; Wait for button release goto EndSW3State4 clrf TMR0 bcf INTCON,T0IF incf StateSW3,f EndSW3State4 return SW3State5 btfss SW3 goto BackToSW3State1 btfss INTCON,T0IF goto EndSW3State5 bcf Flag,ServiceSW3 clrf StateSW3 goto EndSW3State5 BackToSW3State1 decf StateSW3,f EndSW3State5 return ;************************************************************************************ ; ChangeDisplay - Implements a state machine that debounces SW4 and toggles the ; display mode flag. ; ;************************************************************************************ ChangeDisplay movlw high SW4StateTable movwf PCLATH movf StateSW4,w andlw 0x03 ; mask off state pointer addlw low SW4StateTable btfsc STATUS,C incf PCLATH,f movwf PCL SW4StateTable goto SW4State0 goto SW4State1 goto SW4State2 goto SW4State3 SW4State0 movlw 0x01 ; Toggle DisplayMode Flag xorwf Flag,f call DisplayTime ; Display the time incf StateSW4,f return SW4State1 btfss SW4 ; Wait for button release goto EndSW4State1 clrf TMR0 bcf INTCON,T0IF incf StateSW4,f EndSW4State1 return SW4State2 btfss SW4 goto BackToSW4State1 btfsc INTCON,T0IF incf StateSW4,f goto EndSW4State2 BackToSW4State1 decf StateSW4,f EndSW4State2 return SW4State3 bcf Flag,ServiceSW4 clrf StateSW4 return END ; directive 'end of program'