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Renesas SH7641 User Manual

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Section 13 Direct Memory Access Controller (DMAC)

Rev. 4.00 Sep. 14, 2005 Page 443 of 982

REJ09B0023-0400

To execute a longword access to an 8-bit or 16-bit external device or to execute a word access to
an 8-bit external device, the

DACK and TEND outputs are divided for data alignment as shown in

figure 13.18.

CKIO

Address

DACKn

TENDn

WAIT

CSn

T

1

T

2

T

aw

T

1

T

2

(Active low)

(Active low)

Note:

TEND is asserted for the last transfer unit of DMA transfers.

If a transfer unit is divided into multiple bus cycles and
if

CSn is negated during the bus cycle, TEND is also divided.

RD

D15 to D0

WEn

D15 to D0

Read

Write

Figure 13.18 BSC Ordinary Memory Access

(No Wait, Idle Cycle 1, Longword Access to 16-Bit Device)

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