Digi NS9215 manual Channel abort, Flex I/O, Direct

Models: NS9215

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I / O H U B M O D U L E

[Module] DMA RX Buffer Descriptor Pointer

Register

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CE

CA

FLEX

DIRECT

 

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

I/O

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

STATE

INDEX

Register bit

assignment

Bit(s)

Access

Mnemonic

Reset

Description

 

 

 

 

 

 

 

D31

R/W

CE

0x0

Channel enable

 

 

 

 

 

0

Disable DMA operation

 

 

 

 

 

1

Enable DMA operation

 

 

 

 

 

 

 

D30

R/W

CA

0x0

Channel abort

 

 

 

 

 

When set, causes the current DMA operation to

 

 

 

 

 

complete and closes the buffer. The DMA channel

 

 

 

 

 

remains idle until this bit is cleared.

 

 

 

 

 

 

 

 

D29

R/W

FLEX I/O

0x0

0

DMA controlled by CPU

 

 

 

 

 

1

DMA controlled by flexible I/O

 

 

 

 

 

This bit is valid only for channels 0 and 1, which

 

 

 

 

 

 

are assigned to flexible I/O module 0 and

 

 

 

 

 

 

flexible I/O module 1.

 

 

 

 

 

 

 

 

D28

R/W

DIRECT

0x0

0

DMA mode

 

 

 

 

 

1

Direct access mode

 

 

 

 

 

 

 

 

D27:16

N/A

Reserved

N/A

N/A

 

 

 

 

 

 

 

 

D15:10

R

STATE

0x0

DMA state machine status field

 

 

 

 

 

 

 

D09:00

R

INDEX

0x0

This field can be read at any time to determine the

 

 

 

 

 

current index.

 

 

 

 

 

 

 

[ M o d u l e ] D M A R X B u f f e r D e s c r i p t o r P o i n t e r

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Addresses: 9000_0008 / 9000_8008 / 9001_0008 / 9001_8008 / 9002_0008 / 9002_8008 / 9003_0008 / 9003_8008

The DMA RX Buffer Descriptor Pointer register is the address of the first buffer descriptor for each DMA channel.

376

Hardware Reference NS9215

31 March 2008

Page 376
Image 376
Digi NS9215 manual Channel abort, Flex I/O, Direct