Control Registers and Control Packets
788
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Direct Memory Access Controller (DMA) Module
20.3.2 Channel Configuration
The channel configuration is defined by the channel control packet: channel control, transfer count, offset
values, source/destination address.
•
It is stored in local RAM, which is protected by parity.
•
Each control packet contains a total of nine fields.
•
The first six fields are programmable, while the last three fields are read only.
•
The RAM is accessible by queue A and queue B state machines as well as CPU.
•
When there are simultaneous accesses, the priority is resolved in a fixed priority scheme with the CPU
having the highest priority.
All the control packets look the same. Following, there is the detailed layout of these registers shown for
control packet 0.
20.3.2.1 Initial Source Address Register (ISADDR)
Figure 20-110. Initial Source Address Register (ISADDR) [offset = 00]
31
0
ISADDR
R/WP-X
LEGEND: R/W = Read/Write; WP = Write in privilege mode only; X = value is unknown; -
n
= value after reset
Table 20-100. Initial Source Address Register (ISADDR) Field Descriptions
Bit
Field
Description
31-0
ISADDR
Initial source address. These bits give the absolute 32-bit source address (physical).
20.3.2.2 Initial Destination Address Register (IDADDR)
Figure 20-111. Initial Destination Address Register (IDADDR) [offset = 04h]
31
0
IDADDR
R/WP-X
LEGEND: R/W = Read/Write; WP = Write in privilege mode only; X = value is unknown; -
n
= value after reset
Table 20-101. Initial Destination Address Register (IDADDR) Field Descriptions
Bit
Field
Description
31-0
IDADDR
Initial destination address. These bits give the absolute 32-bit destination address (physical).