DMA_TCDn_CITER_ELINKYES field descriptions (continued)
Field Description
NOTE:
When the CITER field is initially loaded by software, it must be set to the same value as that
contained in the BITER field.
NOTE:
If the channel is configured to execute a single service request, the initial values of BITER and
CITER should be 0x0001.
22.3.32 TCD Current Minor Loop Link, Major Loop Count (Channel
Linking Disabled) (DMA_TCDn_CITER_ELINKNO)
If TCDn_CITER[ELINK] is cleared, the TCDn_CITER register is defined as follows.
Address:
4000_8000h base + 1016h offset + (32d × i), where i=0d to 15d
Bit 15 14 13 12 11 10 9 8
Read
ELINK CITER
Write
Reset
x* x* x* x* x* x* x* x*
Bit
7 6 5 4 3 2 1 0
Read
CITER
Write
Reset
x* x* x* x* x* x* x* x*
* Notes:
x = Undefined at reset.•
DMA_TCDn_CITER_ELINKNO field descriptions
Field Description
15
ELINK
Enable channel-to-channel linking on minor-loop complete
As the channel completes the minor loop, this flag enables linking to another channel, defined by the
LINKCH field. The link target channel initiates a channel service request via an internal mechanism that
sets the TCDn_CSR[START] bit of the specified channel.
If channel linking is disabled, the CITER value is extended to 15 bits in place of a link channel number. If
the major loop is exhausted, this link mechanism is suppressed in favor of the MAJORELINK channel
linking.
NOTE:
This bit must be equal to the BITER[ELINK] bit; otherwise, a configuration error is reported.
0 The channel-to-channel linking is disabled
1 The channel-to-channel linking is enabled
CITER Current Major Iteration Count
This 9-bit (ELINK = 1) or 15-bit (ELINK = 0) count represents the current major loop count for the channel.
It is decremented each time the minor loop is completed and updated in the transfer control descriptor
memory. After the major iteration count is exhausted, the channel performs a number of operations, for
Table continues on the next page...
Chapter 22 Enhanced Direct Memory Access (eDMA)
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors 477
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