Dma Transfer End - Renesas H8SX/1500 Series Hardware Manual

Section 7 DMA Controller (DMAC)
7.5

DMA Transfer End

Operations on completion of a transfer differ according to the transfer end condition. DMA
transfer completion is indicated that the DTE and ACT bits in DMDR are changed from 1 to 0.
(1)
Transfer End by DTCR Change from 1, 2, or 4, to 0
When DTCR is changed from 1, 2, or 4 to 0, a DMA transfer for the channel is completed. The
DTE bit in DMDR is cleared to 0 and the DTIF bit in DMDR is set to 1. At this time, when the
DTIE bit in DMDR is set to 1, a transfer end interrupt by the transfer counter is requested. When
the DTCR value is 0 before the transfer, the transfer is not stopped.
(2)
Transfer End by Transfer Size Error Interrupt
When the following conditions are satisfied while the TSEIE bit in DMDR is set to 1, a transfer
size error occurs and a DMA transfer is terminated. At this time, the DTE bit in DMR is cleared to
0 and the ESIF bit in DMDR is set to 1.
• In normal transfer mode and repeat transfer mode, when the next transfer is requested while a
transfer is disabled due to the DTCR value less than the data access size
• In block transfer mode, when the next transfer is requested while a transfer is disabled due to
the DTCR value less than the block size
When the TSEIE bit in DMDR is cleared to 0, data is transferred until the DTCR value reaches 0.
A transfer size error is not generated. Operation in each transfer mode is shown below.
• In normal transfer mode and repeat transfer mode, when the DTCR value is less than the data
access size, data is transferred in bytes
• In block transfer mode, when the DTCR value is less than the block size, the specified size of
data in DTCR is transferred instead of transferring the block size of data. The transfer is
performed in bytes.
(3)
Transfer End by Repeat Size End Interrupt
In repeat transfer mode, when the next transfer is requested after completion of a 1-repeat size data
transfer while the RPTIE bit in DACR is set to 1, a repeat size end interrupt is requested. When
the interrupt is requested to complete DMA transfer, the DTE bit in DMDR is cleared to 0 and the
ESIF bit in DMDR is set to 1. Under this condition, setting the DTE bit to 1 resumes the transfer.
In block transfer mode, when the next transfer is requested after completion of a 1-block size data
transfer, a repeat size end interrupt can be requested.
Rev. 3.00 Mar. 14, 2006 Page 196 of 804
REJ09B0104-0300