NXP Semiconductors Kinetis KE1xZ256, Reference Manual

Page: 244 / 1325

13.4.2 Fault reporting and handling
Channel errors are reported in the Error Status register (DMAx_ES) and can be caused
by:
• A configuration error, which is an illegal setting in the transfer-control descriptor or
an illegal priority register setting in Fixed-Arbitration mode, or
• An error termination to a bus master read or write cycle
A configuration error is reported when the starting source or destination address, source
or destination offsets, minor loop byte count, or the transfer size represent an inconsistent
state. Each of these possible causes are detailed below:
• The addresses and offsets must be aligned on 0-modulo-transfer-size boundaries.
• The minor loop byte count must be a multiple of the source and destination transfer
sizes.
• All source reads and destination writes must be configured to the natural boundary of
the programmed transfer size respectively.
• In fixed arbitration mode, a configuration error is caused by any two channel
priorities being equal. All channel priority levels must be unique when fixed
arbitration mode is enabled.
NOTE
When two channels have the same priority, a channel
priority error exists and will be reported in the Error Status
register. However, the channel number will not be reported
in the Error Status register. When all of the channel
priorities within a group are not unique, the channel
number selected by arbitration is undetermined.
To aid in Channel Priority Error (CPE) debug, set the Halt
On Error bit in the DMA’s Control Register. If all of the
channel priorities within a group are not unique, the DMA
will be halted after the CPE error is recorded. The DMA
will remain halted and will not process any channel service
requests. Once all of the channel priorities are set to unique
numbers, the DMA may be enabled again by clearing the
Halt bit.
Functional description
Kinetis KE1xZ256 Sub-Family Reference Manual, Rev. 3, 07/2018
244 NXP Semiconductors