Maxcntx, Basex – Cirrus Logic EP93xx User Manual

Page 423

Advertising
background image

DS785UM1

10-29

Copyright 2007 Cirrus Logic

DMA Controller

EP93xx User’s Guide

1

0

1

0

10

MAXCNTx

Address:

MAXCNT0: Channel Base Address + 0x0020 - Read/Write
MAXCNT1: Channel Base Address + 0x0030 - Read/Write

Definition:

x = “0” or “1”. Maximum byte count for the buffer. Represents the double buffer
per channel. Only the low order 16 bits are used. Each MAXCNTx register
must be programmed before it’s corresponding BASEx register.

Bit Descriptions:

RSVD:

Reserved. Unknown During Read.

MAXCNTx:

Maximum byte count for the buffer.

BASEx

Address:

BASE0: Channel Base Address + 0x0024 - Read/Write
BASE1: Channel Base Address + 0x0034 - Read/Write

Definition:

Base address for the current and next DMA transfer.

Bit Descriptions:

BASEx:

x = “0” or “1”. Base address for the current and next DMA
transfer. Loaded with start address after enabling the DMA
Channel, the latter event required to take the Channel
State machine into the STALL state, the former event
required to enter the ON State.

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

RSVD

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

MAXCNTx

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

BASEx

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

BASEx

Advertising