evb11.sdi

proteus 仿真实例

,,, ;EVB11 Demo Program
,,, ;A very simple example which implements a
,,, ;terminal echo program and writes the incomming
,,, ;and outgoing characters to some LED displays.
,,,
,,, ACIA_CONTROL    equ $9800
,,, ACIA_STATUS     equ $9800
,,, ACIA_DATA       equ $9801
,,,
,,, PORTC             equ      $1003
,,, PORTB             equ      $1004
,,, PORTCL            equ      $1005
,,, DDRC              equ      $1007
,,,
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,,,                 org $FFFE
FFFE,E0 00,,                 dw start
,,,
,,,                 org $E000
,,,
E000,8E 00 FF,start:, start:          lds  #$FF
,,,
E003,86 03,,                 ldaa #$03                       ; Reset
E005,B7 98 00,,                 staa ACIA_CONTROL
,,,
E008,86 1D,,                 ldaa #$1D                       ; 8 bits, odd, 1 stop, div 16 clocks
E00A,B7 98 00,,                 staa ACIA_CONTROL
,,,
E00D,86 FF,,                 ldaa #$FF
E00F,B7 10 07,,                 staa DDRC
,,,
,,,
E012,B6 98 00,waitrx:, waitrx:         ldaa ACIA_STATUS
E015,84 01,,                 anda #$01
E017,26 07,,                 bne readrx
E019,86 00,,                 ldaa #0
E01B,4A,delay:, delay:          deca
E01C,26 FD,,                 bne delay
E01E,20 F2,,                 bra waitrx
,,,
E020,F6 98 01,readrx:, readrx:         ldab ACIA_DATA
E023,F7 10 04,,                 stab PORTB
,,,
E026,B6 98 00,waittx:, waittx:         ldaa ACIA_STATUS
E029,84 02,,                 anda #$02
E02B,27 F9,,                 beq waittx
,,,
E02D,F7 98 01,,                 stab ACIA_DATA
E030,F7 10 03,,                 stab PORTC
,,,
E033,20 DD,done:, done:           bra waitrx
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