;;;OK
;;;; last modified : 98-3-2,16:00:00
;
;This example implement a simple ohm-measure with MCU ,
;demonstrating how to utilise SX18/28's:
; I/O operation
;
;Hardware:
; Display: 8 segment LCD(working in scaning mode)
; Volatile Resistance: 0--10K
; Immutable Resistance: 10K,series connected with the former
; Standard Resistance: 10K
; Capacitor: 104: 0.01uF
;
; I/O connection:
; ra0--------COM1
; ra1--------COM2
; ra2--------COM3
; ra3--------COM4
;
; rc0--------LCD.a
; rc1--------LCD.b
; rc2--------LCD.c
; rc3--------LCD.d
; rc4--------LCD.e
; rc5--------LCD.f
; rc6--------LCD.g
;
; rb3--------LCD control
; rb5--------Volatile Resistance
; rb6--------Standard Resistance
; rb7--------Detected Pin
; Configuration data
; The Chip's configuration is 28 pin, 2K EEPROM, 136 byte RAM,
; internal 4MHz internal RC driven, single clock per instruction.
; device pins28,pages4,banks8,osc4mhz,turbo,stackx,optionx
RA equ 05h
RB equ 06h
RC equ 07h
PORTA EQU 05H
PORTB EQU 06H
PORTC EQU 07H
INDF EQU 0
TMR0 EQU 1
PCL EQU 2
STATUS EQU 3
FSR EQU 4
RTCC EQU 1H
WREG EQU 1H
PC EQU 2H
C EQU STATUS.0
DC EQU STATUS.1
Z EQU STATUS.2
PD EQU STATUS.3
TO EQU STATUS.4
PA0 EQU STATUS.5
PA1 EQU STATUS.6
PA2 EQU STATUS.7
;port define
common equ ra
com1 equ ra.0
com2 equ ra.1
com3 equ ra.2
com4 equ ra.3
lcd_control equ rb.3
lcd_data equ rc
;Varialbes
temp equ 10h ;1 byte
second equ 0eh
minute equ 0fh
databyte_1 equ 11h
databyte_2 equ 12h
databyte_3 equ 13h
databyte_4 equ 14h
lcd_data_pointer equ 15h
lcd_common_pointer equ 16h
lcd_phase equ 17h
lcd_odd_phase equ 18h
time_countl equ 19h
time_counth equ 1ah
rm_countl equ 1bh
rm_counth equ 1ch
rc_countl equ 1dh
rc_counth equ 1eh
ohm_measure_delay equ 1fh
dec_l equ 0eh
dec_h equ 0fh
dec_u equ 23h
device pins28,pages4,banks8,osc4mhz,turbo,stackx,optionx
reset start
org 0
;jmp InitProg
InitProg ;
; inc second
; sb Z
; jmp InitEnd
; jmp Measure1
InitEnd ;
reti
Measure1 inc databyte_1
mov w,#0fh
and databyte_1,w
mov w,#3
mov databyte_2,w
; call Measure
jmp InitEnd
org $40
start
mov w,#0 ;rc all out
mov !rc,w
mov w,#0 ;ra0..3 out
mov !ra,w
mov w,#%0 ;rb3 out
mov !rb,w
; mov w,#0eh
; mov m,w
mov w,#0e2h ;1110 0010
mov !option,w ; ^^^PS2 PS1 PS0------1:8
; ^--------------------PSA=0 prescaler assigned to RTCC
; ^----------------------RTE_ES=0 RTCC L->H
; ^-----------------------RTS=0 RTCC internal inc
; ^------------------------RTE_IE=0 RTCC interrupt is enabled
;^-------------------------RTW=1 register 01h addresses RTCC
clr ra
clr rb
clr rc
clr rm_countl
clr rm_counth
clr rc_countl
clr rc_counth
call Proc_Init_LCD_Display
loop0
mov w,#0
mov ohm_measure_delay,w
:loop1
call Display ;1
call Proc_Delay
decsz ohm_measure_delay
jmp :loop1
call Measure
jmp loop0
ret
Proc_Delay
mov w,#54 ;67;#100;#135;#100;90;#77;#67;#54;#30;#10;#19
mov time_counth,w
Proc_Delay_1
mov w,#25;#32
mov time_countl,w
; clr time_countl
Proc_Delay_2
decsz time_countl
jmp Proc_Delay_2
decsz time_counth
jmp Proc_Delay_1
ret
proc_read_rtcc
mov w,rtcc
mov rm_countl,w
mov w,#0
mov w,rm_countl-w
sb 3.2 ;z=0
inc rm_counth
ret
Measure
call proc_encharge_rm
call proc_discharge
call proc_bin_bcd
call proc_update_display
Measure_end
ret
proc_discharge
mov w,#000h ;0000 0000
; ^---------------------rb.5 input to detecte Cap is discharged
; ^----------------------rb.6 ouput to discharge the Cap
;^-----------------------rb.7 input to disable
mov !rb,w
:waitdischarge
clrb rb.6
clrb rb.5
clrb rb.7
; snb rb.5
;jmp :waitdischarge
;call proc_delay ;here will restore the portb status
ret
;;;measure the rm value
proc_encharge_rm
mov w,#60h ;0110 0000
; ^---------------------rb.5-input -- detecte
; ^----------------------rb.6 input --disable
;^-----------------------rb.7 output--encharge
mov !rb,w
clr rm_countl
clr rm_counth
mov w,#80h
mov rm_countl,w
setb rb.7 ;begin encharge
wait_encharge_rm
inc rm_countl
snb z ;overflow?
jmp encharge_rm_1
inc rm_counth
snb z ;rm_counth overflow?
dec rm_counth
mov w,#80h
mov rm_countl,w
encharge_rm_1
snb rb.5 ;encharged?
jmp encharge_rm_end
jmp wait_encharge_rm
encharge_rm_end
mov w,#0f0h
sub rm_counth,w
mov w,#020h
sub rm_counth,w
ret
proc_bin_bcd
mov w,rm_counth
clr dec_h
mov dec_l,w
bin_bcd_1
mov w,#10
mov w,dec_l-w
sb 3.0
jmp bin_bcd_end
mov dec_l,w
inc dec_h
jmp bin_bcd_1
bin_bcd_end
; mov w,#9
; mov w,dec_h-w
; snb 3.0
; jmp bin_bcd_end_1
; mov w,#0fh
; mov dec_h,w
; mov dec_l,w
bin_bcd_end_1
clrb 3.0
rl dec_h
rl dec_h
rl dec_h
rl dec_h
mov w,#0f0h
and dec_h,w
mov w,#0fh
and dec_l,w
mov w,dec_l
or w,dec_h
mov rm_counth,w
; mov w,#099h
; mov w,rm_counth-w
; snb 3.0
; jmp bin_bcd_end_2
; mov w,#0ffh
; mov rm_counth,w
bin_bcd_end_2
retw 0
;;;measure the rc value
proc_encharge_rc
mov w,#0a0h ;1010 0000
; ^---------------------rb.5 input-- detecte
; ^----------------------rb.6 ouput-- encharge
;^-----------------------rb.7 input-- disable
mov !rb,w
clr rc_countl
clr rc_counth
mov w,#080h
mov rc_countl,w
setb rb.6 ;begin encharge
wait_encharge_rc
inc rc_countl
snb z ;overflow?
jmp encharge_rc_1
inc rc_counth
mov w,#080h
mov rc_countl,w
encharge_rc_1
snb rb.6
jmp encharge_rc_end
jmp wait_encharge_rc
encharge_rc_end
ret
proc_freq_ohm
mov w,#0b0h
mov w,rc_counth-w
snb 3.0 ;c
clr w
mov temp,w
clrc
rr temp
mov w,temp
mov rc_counth,w
ret
proc_update_display
mov w,rm_counth
mov temp,w
and w,#0fh
mov databyte_1,w
mov w,#0f0h
and temp,w
clrb 3.0
rl temp
rl temp
rl temp
rl temp
mov w,temp
and w,#0fh
mov databyte_2,w
ret
Proc_Init_LCD_Display
;clear buffer
mov w,#$a
mov databyte_1,w
mov w,#$b
mov databyte_2,w
mov w,#$c
mov databyte_3,w
mov w,#$11
mov databyte_4,w
clrb rb.3
mov w,#0
mov lcd_data,w
mov w,#%1111
mov common,w
mov w,#databyte_1
mov lcd_data_pointer,w
mov w,#%0001
mov lcd_phase,w
mov w,#1
mov lcd_odd_phase,w
ret
;LCD SEGMENT CODE TABLE
; org $30
Proc_Seg_Table
jmp pc+w
retw $3f ;0
retw $06 ;1
retw $5b ;2
retw $4f ;3
retw $66 ;4
retw $6d ;5
retw $7d ;6
retw $07 ;7
retw $7f ;8
retw $6f ;9
retw $77 ;A
retw $7c ;b
retw $58 ;c
retw $5e ;d
retw $79 ;E
retw $71 ;F
retw $76 ;H
retw $01 ;1--Com4
retw $02 ;AM
retw $04 ;oo
retw $08 ;TEMP
retw $10 ;PM
retw $20 ;TIMER
retw $40 ;KEEP WARM
Display
mov w,lcd_data_pointer
mov fsr,w
mov w,indf
call Proc_Seg_Table
sb lcd_odd_phase.0
jmp Display_1 ;2468
not w ;1357
mov rc,w
mov w,lcd_phase
mov ra,w
setb rb.3
jmp Display_2
Display_1
mov rc,w ;2468
mov w,lcd_phase
not w
and w,#0fh
mov ra,w
clrb rb.3
inc lcd_data_pointer
mov w,#0fh
and lcd_phase,w
clrb 3.0 ;clear c
rl lcd_phase
mov w,#databyte_2
mov w,lcd_data_pointer-w
sb 3.2
jmp Display_2
mov w,#databyte_1
mov lcd_data_pointer,w
mov w,#%0001
mov lcd_phase,w
Display_2
inc lcd_odd_phase
ret
| file: /Techref/scenix/lcd.src, 7KB, , updated: 1999/6/14 11:14, local time: 2025/5/3 20:00,
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