call init_LCD ; Contains function set & clear screen.
call dsp_fixmsg ; Display fixed message.
; *** Main Loop ***
mainloop
call set_cntmode ; Set count mode. (Gate time etc.)
call dsp_status ; Display status.
MOV f DSPMODE, f ; Check display mode.
btfss status, z ;
goto len_mode ;
call dsp_freq ; Display frequency.
goto cntstart
len_mode
call dsp_leng ; Display wave length.
cntstart
call dsp_goff ; Display "Gate OFF".
call dsp_gon ; Display "Gate ON".
call count ; Count core.
goto mainloop
;-------------------------------------------------------------------------
; Set count mode.
; Input : Port B (Data input port of count mode)
; Output: DSPMODE (Display mode)
; EXT_PSC (External prescaler mode)
; INT_PSC (Internal prescaler mode)
; RESMODE (Resolution mode)
; GATETIME (Gate time in milliseconds)
; W register & variable I will be broken.
;
; Notes: All input ports are negative logic.
;-------------------------------------------------------------------------
set_cntmode
; *** Get count mode from input port ***
MOV f portb, w ; Read input port &
andlw 00111111b ; negate logic.
xorlw 00111111b ;
MOV wf CNTMODE ;
andlw 00000011b ; Get resolution mode.
MOV wf RESMODE ;
rrf CNTMODE, f ; Get internal prescaler mode.
rrf CNTMODE, f ;
MOV f CNTMODE, w ;
andlw 00000011b ;
MOV wf INT_PSC ;
rrf CNTMODE, f ; Get external prescaler mode.
rrf CNTMODE, f ;
MOV f CNTMODE, w ;
andlw 00000001b ;
MOV wf EXT_PSC ;
rrf CNTMODE, f ; Get display mode.
MOV f CNTMODE, w ;
andlw 00000001b ;
MOV wf DSPMODE ;
; *** Set gate time ***
MOV lw FRES_100 ; Set gate time soon if
subwf RESMODE, w ; resolution >= 100 Hz.
btfsc status, c ;
goto set_gtime ;
MOV f EXT_PSC, f ; Check other mode
上一页 [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] 下一页
本文关键字：单片机 PIC单片机，单片机-工控设备 - PIC单片机
