Page 206 - Making PIC Microcontroller Instruments and Controllers

202 COUI|IING PULSES: A PnOGRAiIIIIABLE TACHO ETEB

urPli'ii!!n.1!.{li: Finished pulse counling Program
CI,EAR
DEFITiIE OSC 4

The followinq are lhe lnages of the nwbers and are srored in

befoie we do anythins else. These {ilL be Placed in PORTB to

nunber for each digit.
r'tRME 1999, %11111111 LED iS Lii
lrRxTE 2000, % 0 0 0 0 0 1 1 0 0
wRxtE 200L. %10111110 t
VTRITE 2 OO2, %01001100 2
WRITE 2003, % 0 0 0 1 1 1 0 0 3 for our parlicuLar wirinql
wRrtE 2004. %10110100 4 setup this deflnes lhe
wRtrE 2005, %00010101 5 ren digits lhal] te need,
!rRME 2005, % 0 0 0 0 0 1 0 1 6
wRrrEE 2007, r"10011110
r,tRrrE 2008, %00000100 8
$RITE 2009, % 0 0 0 1 0 1 0 0 9

TRIsA=e"o0010000
ERIsB=%00000000
P VAR BYTE
X VIR BYIA counter variable
A VAR BYTE coluter variabLe
Z VAR BYTE counLer variable
Q l/TR BYTE counter variable
?ULSE_I,EN VAR WORD
VAI-IE VAR WORD value of neironone counts
TOIIAI- VAR WORD value of netronone counts
DIGIT1 VAR BYTE each disit in disPLaY
D!GIT2 VAT BYTE each digit in disPlay
DIGIT3 VAR BYTE each dilrir in displaY
DIGIT4 VIR BYTE each diqlit in disPLaY
sets the initiaL walue for x
P = { 0 0 set pause will be in nicroseconds

Q = 0
MAITiI:
DIGIEl=-1 digits Lo a blank
DIGI12=-1 digrits to a btank
DIGtT3=-1 disits to a blank
DIGIT4=-1 disits Lo a blank