MPASM 03.00 Released COUNT.ASM 3-10-2002 16:22:35 PAGE 1
LOC OBJECT CODE LINE SOURCE TEXT
VALUE
00001 ; COUNT.ASM
00002 ; Copyright (c) 2002, TundraWare Inc.
00003 ;
00004 ; Loosely based on David Tait's LED 'WALK.ASM' Test Program
00005 ; Uses same hardware setup but counts in binary, flashing at
00006 ; full count.
00007
00008 ;;; Generally speaking, UPPER-CASE symbols in the code below are
00009 ;;; defined in the standard MPLAB include file. My code is in
00010 ;;; lower-case.
00011
00012
00013 list p=16F84A
00014 #include <P16F84A.INC>
00001 LIST
00002 ; P16F84A.INC Standard Header File, Version 2.00 Microchip Technology, Inc.
00134 LIST
00015
00016 errorlevel -302 ;suppress bank selection messages
2007 3FF5 00017 __config 3ff5h ;xt osc, watchdog
2000 0001 0002 0003 00018 __idlocs 1234
0004
00019
00020 ;;; Device Constants
00021
00022
00000008 00023 pre1 equ 08h ; prescaler constants
00000009 00024 pre2 equ 09h
0000000A 00025 pre4 equ 0ah
0000000B 00026 pre8 equ 0bh
0000000C 00027 pre16 equ 0ch
0000000D 00028 pre32 equ 0dh
0000000E 00029 pre64 equ 0eh
0000000F 00030 pre128 equ 0fh
00031
00032
00033 ;;; Program Constants
00034
00000005 00035 blinkcnt equ 05h ; number of times to blink
0000000D 00036 bcount equ 0dh ; register to hold blink count
0000000F 00037 maxcnt equ 0fh ; maximum count to display
0000000D 00038 preblink equ pre32 ; prescaler value for blinking
0000000C 00039 precount equ pre16 ; prescaler value for counting
00040
00041 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
00042
00043 ;;;
00044 ; Main program logic
00045 ;;;
00046
0000 200E 00047 begin call portb_w ; setup PORTB for writing
0001 300C 00048 movlw precount ; set prescaler for slow disply
0002 2012 00049 call wdt_pre
MPASM 03.00 Released COUNT.ASM 3-10-2002 16:22:35 PAGE 2
LOC OBJECT CODE LINE SOURCE TEXT
VALUE
0003 300F 00050 movlw maxcnt ; number of counts
0004 0186 00051 clrf PORTB ; all leds off
0005 0063 00052 count sleep ; display current count for a while
0006 0A86 00053 incf PORTB,F ; next value to display
0007 0806 00054 movf PORTB,W ; see if we're displaying 'maxcnt'
0008 390F 00055 andlw 0fh ; mask hi nibble - no LEDs there
0009 3A0F 00056 xorlw maxcnt ; subtract 'maxcnt' from w
000A 1D03 00057 btfss STATUS,Z
000B 2805 00058 goto count ; nope, continue counting
000C 2016 00059 call blink
000D 2800 00060 goto begin
00061
00062 ;;; End of main logic
00063
00064 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
00065
00066 ;;;
00067 ; Supporting Subroutines
00068 ;;;
00069
00070 ;;;
00071 ; Set PORTB To Write
00072 ; Returns with Bank 0 selected
00073 ;;;
00074
000E 1683 00075 portb_w bsf STATUS,RP0 ; select register bank 1
000F 0186 00076 clrf TRISB ; set PORTB to all outputs
0010 1283 00077 bcf STATUS,RP0 ; select register bank 0
0011 0008 00078 return
00079
00080 ;;; End of 'portb_w'
00081
00082
00083 ;;;
00084 ; Set the WDT Prescaler
00085 ; Value required must be passed in w
00086 ; Returns with Bank 0 selected
00087 ;;;
00088
0012 1683 00089 wdt_pre bsf STATUS,RP0 ; select register bank 1
0013 0081 00090 movwf OPTION_REG
0014 1283 00091 bcf STATUS,RP0 ; bank0 so PORTB is addressable
0015 0008 00092 return
00093
00094 ;;; End of 'wdt_pre'
00095
00096
00097 ;;;
00098 ; Blink The Lights
00099 ;;;
00100
0016 300D 00101 blink movlw preblink ; set prescaler for fast blink
0017 2012 00102 call wdt_pre
MPASM 03.00 Released COUNT.ASM 3-10-2002 16:22:35 PAGE 3
LOC OBJECT CODE LINE SOURCE TEXT
VALUE
0018 3005 00103 movlw blinkcnt ; number of times to blink
0019 008D 00104 movwf bcount
001A 0063 00105 bcycle sleep ; display on from caller
001B 0186 00106 clrf PORTB ; display off
001C 0063 00107 sleep
001D 0B8D 00108 decfsz bcount,F ; if zero, we've done 'blinkcnt' repetitions
001E 2820 00109 goto again ; we're not done yet
001F 0008 00110 return ; all done
0020 300F 00111 again movlw maxcnt ; blink again - display on
0021 0086 00112 movwf PORTB
0022 281A 00113 goto bcycle
00114
00115 ;;; End of 'blink'
00116
00117
00118
00119 ;;;
00120 ; EEPROM Contents
00121 ;;;
00122
2100 00123 org 2100h
00124 ;
2100 0024 0049 0064 00125 DE "$Id: count.asm,v 1.9 2002/03/10 15:43:56 tundra Exp tundra $"
003A 0020 0063
006F 0075 006E
0074 002E 0061
0073 006D 002C
0076 0020 0031
002E 0039 0020
0032 0030 0030
0032 002F 0030
0033 002F 0031
0030 0020 0031
0035 003A 0034
0033 003A 0035
0036 0020 0074
0075 006E 0064
0072 0061 0020
0045 007
00126 END
MPASM 03.00 Released COUNT.ASM 3-10-2002 16:22:35 PAGE 4
SYMBOL TABLE
LABEL VALUE
C 00000000
DC 00000001
EEADR 00000009
EECON1 00000088
EECON2 00000089
EEDATA 00000008
EEIE 00000006
EEIF 00000004
F 00000001
FSR 00000004
GIE 00000007
INDF 00000000
INTCON 0000000B
INTE 00000004
INTEDG 00000006
INTF 00000001
IRP 00000007
NOT_PD 00000003
NOT_RBPU 00000007
NOT_TO 00000004
OPTION_REG 00000081
PCL 00000002
PCLATH 0000000A
PORTA 00000005
PORTB 00000006
PS0 00000000
PS1 00000001
PS2 00000002
PSA 00000003
RBIE 00000003
RBIF 00000000
RD 00000000
RP0 00000005
RP1 00000006
STATUS 00000003
T0CS 00000005
T0IE 00000005
T0IF 00000002
T0SE 00000004
TMR0 00000001
TRISA 00000085
TRISB 00000086
W 00000000
WR 00000001
WREN 00000002
WRERR 00000003
Z 00000002
_CP_OFF 00003FFF
_CP_ON 0000000F
_HS_OSC 00003FFE
_LP_OSC 00003FFC
_PWRTE_OFF 00003FFF
_PWRTE_ON 00003FF7
MPASM 03.00 Released COUNT.ASM 3-10-2002 16:22:35 PAGE 5
SYMBOL TABLE
LABEL VALUE
_RC_OSC 00003FFF
_WDT_OFF 00003FFB
_WDT_ON 00003FFF
_XT_OSC 00003FFD
__16F84A 00000001
again 00000020
bcount 0000000D
bcycle 0000001A
begin 00000000
blink 00000016
blinkcnt 00000005
count 00000005
maxcnt 0000000F
portb_w 0000000E
pre1 00000008
pre128 0000000F
pre16 0000000C
pre2 00000009
pre32 0000000D
pre4 0000000A
pre64 0000000E
pre8 0000000B
preblink 0000000D
precount 0000000C
wdt_pre 00000012
MEMORY USAGE MAP ('X' = Used, '-' = Unused)
0000 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXX------------- ----------------
2000 : XXXX---X-------- ---------------- ---------------- ----------------
2100 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXX----
All other memory blocks unused.
Program Memory Words Used: 35
Program Memory Words Free: 989
Errors : 0
Warnings : 0 reported, 0 suppressed
Messages : 0 reported, 2 suppressed
