HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 216

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

DTCRB
DTCRB is initialized to H'00 by a reset and in standby mode.
Bit 7—Data Transfer Master Enable (DTME): Together with the DTE bit in DTCRA, this bit
enables or disables data transfer. When the DTME and DTE bits are both set to 1, the channel is
enabled. When an NMI interrupt occurs DTME is cleared to 0, suspending the transfer so that the
CPU can use the bus. The suspended transfer resumes when DTME is set to 1 again. For further
information on operation in block transfer mode, see section 8.6.6, NMI Interrupts and Block
Transfer Mode.
DTME is set to 1 by reading the register while DTME = 0, then writing 1.
Bit 7
DTME
0
1
Bit
Initial value
Read/Write
Data transfer master enable
Enables or disables data
transfer, together with
the DTE bit, and is cleared
to 0 by an interrupt
Description
Data transfer is disabled (DTME is cleared to 0 when an NMI interrupt
occurs)
Data transfer is enabled
DTME
R/W
7
0
Reserved bit
R/W
—
6
0
Destination address
increment/decrement
Destination address
increment/decrement enable
These bits select whether
the destination address
register (MARB) is incremented,
decremented, or held fixed
during the data transfer
DAID
R/W
5
0
202
DAIDE
R/W
Transfer mode select
Selects whether the
block area is the source
or destination in block
transfer mode
4
0
TMS
R/W
3
0
DTS2B
R/W
2
0
Data transfer select
2B to 0B
These bits select the data
transfer activation source
DTS1B
R/W
1
0
(Initial value)
DTS0B
R/W
0
0