22.3.13 Interrupt Request Register (DMA_INT)
The INT register provides a bit map for the 16 channels signaling the presence of an
interrupt request for each channel. Depending on the appropriate bit setting in the
transfer-control descriptors, the eDMA engine generates an interrupt on data transfer
completion. The outputs of this register are directly routed to the interrupt controller
(INTC). During the interrupt-service routine associated with any given channel, it is the
software’s responsibility to clear the appropriate bit, negating the interrupt request.
Typically, a write to the CINT register in the interrupt service routine is used for this
purpose.
The state of any given channel’s interrupt request is directly affected by writes to this
register; it is also affected by writes to the CINT register. On writes to INT, a 1 in any bit
position clears the corresponding channel’s interrupt request. A zero in any bit position
has no affect on the corresponding channel’s current interrupt status. The CINT register is
provided so the interrupt request for a single channel can easily be cleared without the
need to perform a read-modify-write sequence to the INT register.
Address: 4000_8000h base + 24h offset = 4000_8024h
Bit
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
R
W
Reset
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
R
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
DMA_INT field descriptions
Field
Description
31–16
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
Table continues on the next page...
Chapter 22 Enhanced Direct Memory Access (eDMA)
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
Freescale Semiconductor, Inc.
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