Digi NS7520 manual Buffer not ready interrupt pending, Channel abort interrupt pending

Models: NS7520

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D M A M o d u l e

 

 

 

 

 

 

 

 

 

 

Bits

Access

Mnemonic

Reset

Description

 

 

 

 

 

D29

R/C

NRIP

0

Buffer not ready interrupt pending

 

 

 

 

Set when the DMA channel encounters a buffer

 

 

 

 

descriptor whose F bit is in the incorrect state.

 

 

 

 

When NRIP 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 NRIP is cleared by firmware, the buffer

 

 

 

 

descriptor is tried again.

 

 

 

 

 

D28

R/C

CAIP

0

Channel abort interrupt pending

 

 

 

 

Set when the DMA channel finds that the CA bit is

 

 

 

 

set in the DMA Control register. When CAIP is set,

 

 

 

 

the DMA channel stops until the bit is cleared by

 

 

 

 

firmware. The DMA channel automatically goes to

 

 

 

 

the next buffer descriptor when CAIP is cleared.

 

 

 

 

The CA bit in the DMA Control register must be

 

 

 

 

cleared, using firmware, before CAIP is cleared.

 

 

 

 

Otherwise, the next buffer descriptor aborts as

 

 

 

 

well.

 

 

 

 

 

D27

R/C

PCIP

0

Premature complete interrupt pending

 

 

 

 

Set when the DMA channel, configured to operate

 

 

 

 

in fly-by read mode, receives an end-of-transfer

 

 

 

 

indicator from the peripheral while processing a

 

 

 

 

DMA buffer descriptor. The DMA channel goes to

 

 

 

 

the next buffer descriptor.

 

 

 

 

NCIP is set when PCIP is set, for backward

 

 

 

 

compatibility.

 

 

 

 

 

D26:25

N/A

Reserved

N/A

N/A

 

 

 

 

 

D24

R/W

PCIE

0

Premature complete interrupt enable

 

 

 

 

 

D23

R/W

NCIE

0

Normal completion interrupt enable

 

 

 

 

 

D22

R/W

ECIE

0

Error completion interrupt enable

 

 

 

 

 

D21

R/W

NRIE

0

Buffer not ready interrupt enable

Table 51: DMA Status/Interrupt Enable register bit definition

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Page 157
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Digi NS7520 Buffer not ready interrupt pending, Channel abort interrupt pending, Premature complete interrupt pending