Holtek HT-IDE, Руководство пользователя

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org 04h ;external interrupt subroutine
reti ;for safeguard
org 08h ;timer/event 0 interrupt subroutine
reti ;for safeguard
org 0ch ;timer/event 1 interrupt subroutine
reti ;for safeguard
start: ;
clr intc ;initialize registers
clr tmrc ;to guarantee performance
clr tmr ;(interrupts)
set pac ;(ports)
set pbc ;(input mode)
set pcc ;
main:
clr LCM_DATA_CTRL ;set LCM data port to output port
clr LCM_CTRL_CTRL ;set LCM control port to output port
clr LCM_DATA
clr LCM_CTRL
DISPLAY_INIT:
ifdef four_bit ;
mov a,20h ;4-bit mode
else
mov a,30h ;8-bit mode
endif
mov LCM_DATA,a
set LCM_CTRL.E ;write instruction code to
clr LCM_CTRL.E ;initalize LCM
LCM_DELAY: ;delay for LCM setup timing
mov a,0ffh ;need about 4.5ms
mov counter1,a
mov counter0,a
lp0:
sdz counter1
jmp lp0
sdz counter0
jmp lp0
CMD_SEQ:
ifdef four_bit ;
mov a,28h ;4-bit mode and 2 lines (2 pass/byte)
else ;28h for 2 lines and 20h for 1 line
mov a,38h ;8-bit mode and 2 lines
endif ;38h for 2 lines and 30h for 1 line
mov LCM_DATA,a ;
set LCM_CTRL.E
clr LCM_CTRL.E
ifdef four_bit
mov a,80h ;4-bit high nibble (2nd pass)
endif
mov LCM_DATA,a ;write instruction code
HT-IDE User’s Guide
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