D M A c h a n n e l r e g i s t e r s

DMA Status/Interrupt Enable register

Address: FF90 0014 / 34 / 54 / 74 / 94 / B4 / D4 / F4 / 114 / 134 / 154 / 174 / 194 / 1B4 / 1D4 / 1F4

The interrupt enable (IE) bits can be set to cause an interrupt to occur when the corresponding interrupt status bit is set in the DMA Status register. The interrupt pending (IP) bits are set to indicate begin active. These bits are cleared by writing a 1 to the same bit locations.

31

30

29

28

27

26

25

24

23

 

22

21

20

19

18

17

16

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NCIP

ECIP

NRIP

CAIP

PCIP

Reserved

PCIE

NCIE

 

ECIE

NRIE

CAIE

WRAP

IDONE

LAST

FULL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15

14

13

12

11

10

9

8

7

 

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Rsvd

 

 

 

 

 

 

 

BLEN

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Register bit assignment

Bits

Access

Mnemonic

Reset

Description

 

 

 

 

 

D31

R/C

NCIP

0

Normal completion interrupt pending

 

 

 

 

Set when a buffer descriptor has been closed (for

 

 

 

 

normal conditions) and either the NCIE bit is set or

 

 

 

 

the IDONE bit is active in the current buffer

 

 

 

 

descriptor. A normal DMA channel completion

 

 

 

 

occurs when the BLEN count expires (gets to 0) or

 

 

 

 

when a peripheral device signals completion.

 

 

 

 

 

D30

R/C

ECIP

0

Error completion interrupt pending

 

 

 

 

Set when the DMA channel encounters either a

 

 

 

 

bad buffer descriptor pointer or a bad data buffer

 

 

 

 

pointer. When ECIP is set, the DMA channel stops

until the bit is cleared by firmware; the DMA channel does not go to the next buffer descriptor.

When ECIP is cleared, the buffer descriptor is tried again from where it left off. The CA bit in the DMA Control register can be used to abort the current buffer descriptor and go to the next descriptor.

Table 51: DMA Status/Interrupt Enable register bit definition

1 4 2

N S 7 5 2 0 H a r d w a r e R e f e r e n c e , R e v . D 0 3 / 2 0 0 6

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Image 156
Digi NS7520 manual DMA Status/Interrupt Enable register bit definition, Normal completion interrupt pending