Control Registers and Control Packets
566
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Direct Memory Access Controller (DMA) Module
16.3.1.4 HW Channel Enable Set and Status Register (HWCHENAS)
Figure 16-21. HW Channel Enable Set and Status Register (HWCHENAS) [offset = 14h]
31
16
Reserved
R-0
15
0
HWCHENA[15:0]
R/WP-0
LEGEND: R/W = Read/Write; R = Read only; WP = Write in privilege mode only; -
n
= value after reset
Table 16-13. HW Channel Enable Set and Status Register (HWCHENAS) Field Descriptions
Bit
Field
Value
Description
31-16
Reserved
0
Reads return 0. Writes have no effect.
15-0
HWCHENA[
n
]
Hardware channel enable bit. Bit 0 corresponds to channel 0, bit 1 corresponds to channel 1, and
so on. An active hardware DMA request cannot initiate a DMA transfer unless the corresponding
hardware enable bit is set.
The corresponding hardware enable bit is cleared automatically for the following conditions:
• At the end of a block transfer if the auto-initiation bit AIM (see CHCTRL) is not active.
• If an AHB bus error is detected for an active channel.
Reading from HWCHENAS gives the status (enabled/disabled) of channels 0 through 15.
0
The corresponding channel is disabled for hardware triggering.
1
The corresponding channel is enabled for hardware triggering.
16.3.1.5 HW Channel Enable Reset and Status Register (HWCHENAR)
Figure 16-22. HW Channel Enable Reset and Status Register (HWCHENAR) [offset = 1Ch]
31
16
Reserved
R-0
15
0
HWCHDIS[15:0]
R/WP-0
LEGEND: R/W = Read/Write; R = Read only; WP = Write in privilege mode only; -
n
= value after reset
Table 16-14. HW Channel Enable Reset and Status Register (HWCHENAR) Field Descriptions
Bit
Field
Value
Description
31-16
Reserved
0
Reads return 0. Writes have no effect.
15-0
HWCHDIS[
n
]
HW channel disable bit. Bit 0 corresponds to channel 0, bit 1 corresponds to channel 1, and so on.
0
Read: The corresponding channel is disabled for HW triggering.
Write: No effect.
1
Read: The corresponding channel is enabled for HW triggering.
Write: The corresponding channel is disabled.