adc-44d ETC-unknow, adc-44d Datasheet - Page 66

• Manufacturer Part Number: adc-44d
• Description: Multi-function Analogue Input/output Card
• Manufacturer: ETC-unknow

Page 58
127-170
2000 REM PROGRAM THE DMA CONTROLLER
2005 REM FIRST EXTRACT THE SEGMENT AND OFFSET
2010 seg = VARSEG(DAT%(0))
2020 offs = VARPTR(DAT%(0))
2025 REM Transfer the Logical SEGMENT:OFFSET address
2027 REM into a physical PAGE:OFFSET address
2030 PAGE& = seg1% AND &HF000
2040 PAGE& = PAGE& / 4096
2050 PAGE& = PAGE& AND 15
2060 OFFSET& = seg
2070 OFFSET& = OFFSET& * 16
2080 OFFSET& = OFFSET& + offs
2090 OFFSET& = OFFSET& AND 65535
2100 REM Set-up the DMA registers.
2105 OUT (&HA),7: REM DISABLE DMA CHANNEL 3
2110 OUT (&HC), 0: REM RESET BYTE SELECT FF
2120 OUT (&HB), &H47: REM AUTO INC ON CH3,WRITE
2130 OUT (&H82), PAGE&: REM SET PAGE FOR DMA CH3
2150 OUT (&H6), (OFFSET& AND 255): REM SET UP START
2160 OUT (&H6), (OFFSET& AND &HFF00) / 256: REM SET
2170 OUT (&H7), length% AND 255: REM BYTE COUNT LS 8
2180 OUT (&H7), length% / 256: REM BYTE COUNT MS
2190 OUT (&HA), 3: REM ENABLE DMA TXFER
2200 RETURN
ADDRESS OF OUR DATA
TRANSFER, SINGLE MODE
FOR LS 8 BITS
UP START FOR MS 8 BITS
BITS
BITS
How to Use DMA
Blue Chip Technology Ltd.
Appendix C