1 usb hc hcca register-mbar + 0x1018, Usb hc hcca register—mbar + 0x1018 -13, Usb hc hcca register -13 – Freescale Semiconductor MPC5200B User Manual

Page 416: Usb hc hcca register, Usb hc period current endpoint descriptor register, 0x10

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Host Control (HC) Operational Registers

MPC5200B Users Guide, Rev. 1

Freescale Semiconductor

12-13

USB HC Bulk Current Endpint Descriptor Register

(0x102C)

USB HC Done Head Register

(0x1030)

12.4.3.1

USB HC HCCA Register—MBAR + 0x1018

The HC HCCA register contains the physical address of the Host Controller Communication Area. HCD determines alignment restrictions
by writing all 1s to HcHCCA and reading the HcHCCA content. Alignment is evaluated by examining the number of 0s in the lower order
bits. Minimum alignment is 256Bytes. Bits 0 through 7 must always return 0 when read. This area holds control structures and the interrupt
table, which are accessed by both the HC and HCD.

12.4.3.2

USB HC Period Current Endpoint Descriptor Register —MBAR + 0x101C

The HC Period Current Endpoint Descriptor (ED) register contains the physical address of the current isochronous or interrupt endpoint
descriptor.

Table 12-7. USB HC HCCA Register

msb 0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

R

HCCA

W

RESET:

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31 lsb

R

HCCA

Reserved

W

RESET:

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bits

Name

Description

0:23

HCCA

Host Controller Communication Area—base address.

24:31

Reserved

Table 12-8. USB HC Period Current Endpoint Descriptor Register

msb 0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

R

PCED

W

RESET:

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31 lsb

R

PCED

Reserved

W

RESET:

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bits

Name

Description

0:27

PCED

PeriodCurrentED—HC uses this field to point to the head of one of the Periodic lists, which is
processed in the current Frame. HC updates register content after a periodic ED is processed.
HCD may read the content in determining which ED is currently being processed at the time
of reading.

28:31

Reserved

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