D12320VF25IV Datasheet, PDF (376/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 8 Data Transfer Controller
[4] Write 1 to the SWDTE bit and the vector number (H'60) to DTVECR. The write data is H'E0.
[5] Read DTVECR again and check that it is set to the vector number (H'60). If it is not, this
indicates that the write failed. This is presumably because an interrupt occurred between steps
[3] and [4] and led to a different software activation. To activate this transfer, go back to step
[3].
[6] If the write was successful, the DTC is activated and a block of 128 bytes of data is transferred.
[7] After the transfer, an SWDTEND interrupt occurs. The interrupt handling routine should clear
the SWDTE bit to 0 and perform other wrap-up processing.
8.4 Interrupts
An interrupt request is issued to the CPU when the DTC finishes the specified number of data
transfers, or a data transfer for which the DISEL bit was set to 1. In the case of interrupt activation,
the interrupt set as the activation source is generated. These interrupts to the CPU are subject to
CPU mask level and interrupt controller priority level control.
In the case of activation by software, a software activated data transfer end interrupt (SWDTEND)
is generated.
When the DISEL bit is 1 and one data transfer has ended, or the specified number of transfers
have ended, after data transfer ends, the SWDTE bit is held at 1 and an SWDTEND interrupt is
generated. The interrupt handling routine should clear the SWDTE bit to 0.
When the DTC is activated by software, an SWDTEND interrupt is not generated during a data
transfer wait or during data transfer even if the SWDTE bit is set to 1.
Rev.6.00 Sep. 27, 2007 Page 344 of 1268
REJ09B0220-0600