h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 220

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 8 Data Transfer Controller (DTC)
8.3.2
The DTC operates when activated by an interrupt or by a write to DTVECR by software. An
interrupt request can be directed to the CPU or DTC, as designated by the corresponding DTCER
bit. An interrupt becomes a DTC activation source when the corresponding bit is set to 1, and a
CPU interrupt source when the bit is cleared to 0.
At the end of a data transfer (or the last consecutive transfer in the case of chain transfer), the
activation source or corresponding DTCER bit is cleared. Table 8.3 shows activation source and
DTCER clearance. The activation source flag, in the case of RXI0, for example, is the RDRF flag
of SCI0.
Table 8.3
Figure 8.3 shows a block diagram of activation source control. For details see section 5, Interrupt
Controller.
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REJ09B0257-0500
Activation Source
Software activation
Interrupt activation
Activation Sources
Activation Source and DTCER Clearance
When the DISEL Bit Is 0 and
the Specified Number of
Transfers Have Not Ended
The SWDTE bit is cleared to 0
The corresponding DTCER bit
remains set to 1
The activation source flag is
cleared to 0
When the DISEL Bit Is 1, or when
the Specified Number of Transfers
Have Ended
An interrupt is issued to the CPU
The corresponding DTCER bit is cleared
to 0
The activation source flag remains set to 1
A request is issued to the CPU for the
activation source interrupt
The SWDTE bit remains set to 1