1er code
http://www.melabs.com/resources/samples ... ounter.zipCode:
' Pulse counter
' =============
'
' File name : Count_Display.bas
' Company : Mister E
' Programmer : Steve Monfette
' Date : 27/12/2004
' Device : PIC16F84A-20/P
'
'
' This program display to 3 x 7 segments dislay the result of
' pulses count on PORTA.4 pin/sec.
'
'
' Hardware connection :
' ---------------------
' 1. 3 X 7 segments display on PORTB<7:0>
' 2. 3 X PNP transistor on PORTA<3:0> to drive common anode
' of each 7 segments display
'
'
' Programming mode and PIC define
' -------------------------------
'
@ __config _HS_OSC & _WDT_ON & _PWRTE_ON
' HS oscillator
' Enable watch dog timer
' Enable power up timer
'
DEFINE OSC 20 ' use 20 MHZ oscillator
' I/O Definition
' --------------
'
TRISA = %11110000 ' PORTA : <2:0> outputs to common Anode of 7 segment
' 1. PORTA.0 More significant
' 2. PORTA.2 Less significant
' : PORTA.4 input for signal
'
TRISB = 0 ' PORTB connected to 7 segments
' B0 : segment a
' B1 : segment b
' B2 : segment c
' B3 : segment d
' B4 : segment e
' B5 : segment f
' B6 : segment g
' B7 : segment decimal dot
' Internal EEPROM definition
' --------------------------
'
data @0,192,249,164,176,153,146,130,248,128,144 ' table to convert
' numbers to 7 segments
' pattern output when
' drive invert
' Interrupt and register definition
' ---------------------------------
'
OPTION_REG = %1111000 ' TMR0 clock source : RA4/T0CKI
' increment on low to high transition
' Prescaler assign to WDT
' WDT rate 1:1
'
INTCON = %10100000 ' Enable global interrupt
' Disable EE write interrupt
' Enable TMR0 overflow interrupt
' Variable definition
' -------------------
'
DisplayPort var PORTB ' Port for 7 Segments
ClockInput var PORTA.4 ' Input pin for signal
_7Seg1 con 14 ' enable more significant 7 segment display
_7Seg2 con 13 ' enable mid significant 7 segment display
_7Seg3 con 11 ' enable less significant 7 segment display
Digit_1 var byte ' Hundreds digit
Digit_2 var byte ' Tenth digit
Digit_3 var byte ' Unit digit
ToBeDisplay var word ' Result of count to be send to 7 segment display
Display var byte ' Temp variable
DisplayLoop var byte '
Delay var word ' Variable for Delay loop
OverFlowVar var word '
Thousands var bit ' Flag for count >= 1000 & < 10 000
TenThousands var bit ' Flag for count >= 10 000
' Variable and software initialisation
' ------------------------------------
'
tobedisplay = 0 ' set initial value of count
TMR0 = 0 ' reset prescaller
on interrupt goto SetVarToBeDisplay
MainLoop:
' MainLoop
' ---------
'
' 1. display the result of the count on RA4 pin
' 2. refresh display
' 3. reset Timer0
' 4. reload prescaler.
'
' Duration of the procedure : 1 sec
' fine tuned by DelayBetweenEachDisplay Sub
'
' Looping 1 sec and get results of the pulse count in
' TMR0 + OverFlowVar
'
DisplayRefresh:
'
' Testing amount of count
' -----------------------
'
' Get the result of count and place decimal point flag
' on the according 7 segments
'
If tobedisplay>=1000 then
tobedisplay=tobedisplay/10
if tobedisplay>=1000 then
tobedisplay=tobedisplay/10
Thousands=0
TenThousands=1
else
TenThousands=0
thousands=1
endif
else
thousands=0
tenthousands=0
endif
'
' convert digit to 7 segment output pattern
' -----------------------------------------
display=ToBeDisplay dig 2 ' Read hundreds digit
read display,digit_1 ' Convert hundreds
if thousands==1 then digit_1=digit_1 & $7F ' enable decimal dot
' by clearing PORTB.7
display=ToBeDisplay dig 1 ' Read tenths digit
read display,digit_2 ' Convert tenths
if tenthousands==1 then digit_2=digit_2 & $7F ' enable decimal dot '
' by clearing PORTB.7
display=ToBeDisplay dig 0 ' Read units digit
read display,digit_3 ' Convert units
'
'
' Send digit to 7 segments
' ------------------------
for displayloop = 0 to 111 ' loop for about 1 sec
' display hundreds
' ----------------
PORTA=_7seg1 ' enable hundreds 7 segment
displayport=digit_1 ' display
gosub DelayBetweenEachDigit
' display tenth
' -------------
PORTA=_7seg2 ' enable tenth 7 segment
displayport=digit_2 ' display
gosub DelayBetweenEachDigit
' display units
' -------------
PORTA=_7seg3 ' enable unit 7 segment
displayport=digit_3 ' display
gosub DelayBetweenEachDigit
next
tobedisplay = OverFlowVar + TMR0
OverFlowVar = 0 ' Reset OverFlowVar
TMR0 = 0 ' reset prescaller
goto DisplayRefresh
DelayBetweenEachDigit:
' DelayBetweenEachDigit
' ---------------------
' Produce delay of about 3 mSec
'
' Fine tuned with MPLAB StopWatch to get MainLoop = 1 sec
'
for delay=1 to 307
@ nop
next
@ nop
@ nop
@ nop
@ nop
@ nop
@ nop
@ nop
return
disable
SetVarToBeDisplay:
'
' SetVarToBeDisplay
' -----------------
' interrupt routine of TMR0 overflow
'
' Reset prescaller
' Reset overflow flag
'
OverFlowVar = OverFlowVar + 256
INTCON.2 = 0 ' clear overflow flag
TMR0 = 0 ' reload TMR0
resume
