Specifications

Application Examples
; CALLS: NONE
; DESTROYS: FLAGS
DCU_READ PROC
; PRESERVE REGISTER STATUS
PUSH AX
PUSH BX
PUSH CX
PUSH DX
; SET UP ADDRESS REGISTERS
MOV AX,SEG DATA
MOV DX,OFFSET DMA_BUF
MOV BL,AH
MOV CL,4
SHL AX,CL
SHR BL,CL
ADD DX,AX
ADC BL,0
MOV DX,DCU_DBA_OFF
MOV AX,DX
OUT DX,AX
MOV DX,DCU_DBA_SEG
MOV AX,BX
OUT DX,AL
; SET UP COUNT REGISTERS
MOV AX,SIZE DMA_BUF
MOV DX,DCU_DBC
OUT DX,AX
; SET UP MODE AND ENABLE
PUT DCU_DMD,DCU_DMD_READ
PUT DCU_DMK,DCU_DMK_INIT
; RESTORE REGISTER STATUS
POP DX
POP CX
POP BX
POP AX
; RESTORE REGISTER STATUS
POP DX
POP CX
POP AX
DCU_READ ENDP
CODE ENDS
END MAIN
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