HD6417615 Hitachi Semiconductor, HD6417615 Datasheet - Page 479

• Manufacturer Part Number: HD6417615
• Description: Hardware Manual
• Manufacturer: Hitachi Semiconductor

Bit 0—DMA Enable Bit (DE): Enables or disables DMA transfers. In auto-request mode, the
transfer starts when this bit or the DME bit in DMAOR is set to 1. The NMIF and AE bits in
DMAOR and the TE bit must be all set to 0. In external request mode or on-chip peripheral
module request mode, the transfer begins when the DMA transfer request is received from the
relevant device or on-chip peripheral module, provided this bit and the DME bit are set to 1. As
with the auto-request mode, the TE bit and the NMIF and AE bits in DMAOR must all be set to 0.
The transfer can be stopped by clearing this bit to 0. The DE bit is initialized to 0 by a reset and in
standby mode. Its value is retained during a module standby.
Bit 0: DE
0
1
11.2.5
DMA vector number registers 0 and 1 (VCRDMA0, VCRDMA1) are 32-bit read/write registers
that set the DMAC transfer-end interrupt vector number. Only the lower eight bits of the 32 are
valid. They are written as 32-bit values, including the upper 24 bits. Write the initial values to the
upper 24 bits. These bits return 0 if read. Values are retained in a reset, in standby mode, and when
the module standby function is used.
Bits 31 to 8—Reserved: These bits are always read as 0. The write value should always be 0.
Bits 7 to 0—Vector Number Bits 7–0 (VC7–VC0): Set the interrupt vector numbers at the end of a
DMAC transfer. Interrupt vector numbers of 0–127 can be set. When a transfer-end interrupt
occurs, the vector number is fetched and control is transferred to the specified interrupt handling
routine. The VC7–VC0 bits retain their values in a reset and in standby mode. As the maximum
vector number is 127, 0 must always be written to VC7.
464
Initial value:
Initial value:
DMA Vector Number Registers 0 and 1 (VCRDMA0, VCRDMA1)
R/W:
R/W:
Bit:
Bit:
VC7
R/W
31
—
—
0
R
7
Description
DMA transfer disabled
DMA transfer enabled
VC6
R/W
30
—
—
0
R
6
VC5
R/W
29
—
—
0
R
5
VC4
R/W
…
…
…
…
—
4
VC3
R/W
11
—
—
0
R
3
VC2
R/W
10
—
—
0
R
2
VC1
R/W
—
—
9
0
R
1
(Initial value)
VC0
R/W
—
—
8
0
R
0