HD6432351 datasheet(296/1025 Pages) RENESAS

296 / 1025 page

Section 7 DMA Controller (DMAC)

Rev. 3.00 Sep 15, 2006 page 262 of 988

REJ09B0330-0300

External

memory

External

device

(Read)

(Write)

HWR, LWR

A23 to A0

H8S/2350 Group

D15 to D0

(high impedance)

DACK

Address bus

Figure 7.17 Data Bus in Single Address Mode

When using the DMAC for single address mode reading, transfer is performed from external

memory to the external device, and the

DACK pin functions as a write strobe for the external

device. When using the DMAC for single address mode writing, transfer is performed from the

external device to external memory, and the

DACK pin functions as a write strobe for the external

device. Since there is no directional control for the external device, one or other of the above

single directions should be used.

Bus cycles in single address mode are in accordance with the settings of the bus controller for the

external memory area. On the external device side,

DACK is output in synchronization with the

address strobe. For details of bus cycles, see section 7.5.11, DMAC Bus Cycles (Single Address

Mode).

Do not specify internal space for transfer addresses in single address mode.

HD6432351 Datasheet(PDF) 296 Page - Renesas Technology Corp