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3 asynchronous transmit retries register, 4 csr data register – Texas Instruments TSB12LV26 User Manual

Page 44

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4–6

4.3

Asynchronous Transmit Retries Register

The asynchronous transmit retries register indicates the number of times the TSB12LV26 attempts a retry for
asynchronous DMA request transmit and for asynchronous physical and DMA response transmit. See Table 4–4 for
a complete description of the register contents.

Bit

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

Name

Asynchronous transmit retries

Type

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

Default

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bit

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Name

Asynchronous transmit retries

Type

R

R

R

R

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Default

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Register:

Asynchronous transmit retries

Type:

Read/Write, Read-only

Offset:

08h

Default:

0000 0000h

Table 4–4. Asynchronous Transmit Retries Register Description

BIT

FIELD NAME

TYPE

DESCRIPTION

31–29

secondLimit

R

The second limit field returns 0s when read, since outbound dual-phase retry is not implemented.

28–16

cycleLimit

R

The cycle limit field returns 0s when read, since outbound dual-phase retry is not implemented.

15–12

RSVD

R

Reserved. Bits 15–12 return 0s when read.

11–8

maxPhysRespRetries

R/W

This field tells the physical response unit how many times to attempt to retry the transmit operation
for the response packet when a busy acknowledge or ack_data_error is received from the target
node.

7–4

maxATRespRetries

R/W

This field tells the asynchronous transmit response unit how many times to attempt to retry the
transmit operation for the response packet when a busy acknowledge or ack_data_error is
received from the target node.

3–0

maxATReqRetries

R/W

This field tells the asynchronous transmit DMA request unit how many times to attempt to retry the
transmit operation for the response packet when a busy acknowledge or ack_data_error is
received from the target node.

4.4

CSR Data Register

The CSR data register is used to access the bus management CSR registers from the host through compare-swap
operations. This register contains the data to be stored in a CSR if the compare is successful.

Bit

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

Name

CSR data

Type

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

Default

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

Bit

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Name

CSR data

Type

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

Default

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

Register:

CSR data

Type:

Read-only

Offset:

0Ch

Default:

XXXX XXXXh