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Models: NS9215

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

[Module] DMA TX Control

[ M o d u l e ] D M A T X C o n t r o l

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

Addresses: 9000_0018 / 9000_8018 / 9001_0018 / 9001_8018 / 9002_0018 / 9002_8018 / 9003_0018

The DMA TX Control register contains control register settings for each transmit DMA channel.

Register

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

CE

CA

FLEX DIRECT INDEXEN I/O

Reserved

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 module

 

 

 

 

 

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

R/W

INDEXEN

0x0

0

Hardware will not use the INDEX field when

 

 

 

 

 

 

in the idle state

 

 

 

 

 

1

Hardware will use the INDEX field when in

 

 

 

 

 

 

the idle state

 

 

 

 

 

 

 

 

D26:16

N/A

Reserved

N/A

N/A

 

 

 

 

 

 

 

 

D15:10

R

STATE

0x0

DMA state machine status field

 

 

 

 

 

 

 

D09:00

R/W

INDEX

0x0

When the state machine is in the idle state, this

 

 

 

 

 

register can be used to change the index. This field

 

 

 

 

 

can be read at any time to determine the current

 

 

 

 

 

index.

 

 

 

 

 

 

 

380

Hardware Reference NS9215

31 March 2008

Page 380
Image 380
Digi NS9215 manual D u l e D M a T X C o n t r o l, Indexen