80C186EC/80C188EC Microprocessor User's Manual

DIRECT MEMORY ACCESS UNIT
SECTORS
MOV AX, 512 ; THE DISK READS IN 512 BYTE
MOV DX, D1TC ; XFER COUNT REG
OUT DX, AX
; NOW WE NEED TO SET THE PARAMETERS FOR THE CHANNEL AS FOLLOWS:
;
; DESTINATION SOURCE
; ----------- ------
; MEMORY SPACE I/O SPACE
; INCREMENT PTR CONSTANT PTR
;
; TERMINATE ON TC, INTERRUPT, SOURCE SYNC, HIGH PRIORITY RELATIVE TO
; CHANNEL 0, BYTE XFERS, USE DRQ PIN FOR REQUEST SOURCE. ARM CHANNEL.
MOV
MOV
OUT
AX, 1010001101100110B
DX, D0CON
DX, AX
; REQUESTS ON DRQ1 WILL NOW RESULT IN TRANSFERS
CODE_SEG
DATA_SEG
ENDS
SEGMENT
SOURCE_DATA_1DB '80C186EC INTEGRATED PROCESSOR'
DEST_DATA_1DB 30 DUP('MITCH') ; JUNK DATA FOR TEST
DISK_BUFF DB
512 DUP()
DATA_SEG
ENDS
END START
Example 10-1. Initializing the DMA Unit (Continued)
10-33