Registers
1751
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Universal Serial Bus 2.0 (USB) Controller
34.4.82 Queue Manager Linking RAM Region 0 Size Register (LRAM0SIZE)
The queue manager linking RAM region 0 size register (LRAM0SIZE) sets the size of the array of linking
pointers that are located in Region 0 of Linking RAM. The size specified the number of descriptors for
which linking information is stored in this region. It does not support byte accesses. The queue manager
linking RAM region 0 size register (LRAM0SIZE) is shown in
and described in
Figure 34-108. Queue Manager Linking RAM Region 0 Size Register (LRAM0SIZE)
31
16
Reserved
R-0
15
14
13
0
Reserved
REGION0_SIZE
R-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 34-112. Queue Manager Linking RAM Region 0 Size Register (LRAM0SIZE)
Field Descriptions
Bit
Field
Value
Description
31-14
Reserved
0
Reserved
13-0
REGION0_SIZE
0-3FFFh
This field indicates the number of entries that are contained in the linking RAM region 0. A
descriptor with index less than region0_size value has its linking location in region 0. A
descriptor with index greater than region0_size has its linking location in region 1. The queue
manager will add the index (left shifted by 2 bits) to the appropriate regionX_base_addr to get
the absolute 32-bit address to the linking location for a descriptor.
34.4.83 Queue Manager Linking RAM Region 1 Base Address Register (LRAM1BASE)
The queue manager linking RAM region 1 base address register (LRAM1BASE) is used to set the base
address for the first portion of the Linking RAM. This address must be 32-bit aligned. It is used by the
Queue Manager to calculate the 32-bit linking address for a given descriptor index. It does not support
byte accesses. The queue manager linking RAM region 1 base address register (LRAM1BASE) is shown
in
and described in
.
Figure 34-109. Queue Manager Linking RAM Region 1 Base Address Register (LRAM1BASE)
31
0
REGION1_BASE
R/W-0
LEGEND: R/W = Read/Write; -
n
= value after reset
Table 34-113. Queue Manager Linking RAM Region 1 Base Address Register (LRAM1BASE)
Field Descriptions
Bit
Field
Value
Description
31-0
REGION1_BASE
0-FFFF FFFFh
This field stores the base address for the second region of the linking RAM. This may be
anywhere in 32-bit address space but would be typically located in off-chip memory.