SH7708 datasheet(266/633 Pages) RENESAS

No. de pieza	SH7708

Descripción Electrónicos	SuperH??RISC engine

PDF	633 Pages

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Fabricante Electrónico	RENESAS [Renesas Technology Corp]

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EDO Mode: In DRAM, an extended data out (EDO) mode is also provided in which, once the

CAS signal is asserted while the RAS signal is asserted, even if the CAS signal is negated, data is

output to the data bus until the

CAS signal is next asserted. (This is in addition to the mode in

which data is output to the data bus only while the

CAS signal is asserted in a data read cycle.) In

the SH7708 Series, the EDO mode bit (EDOMODE) in MCR enables selection, for area 3 DRAM

only, of either normal access/burst access using high-speed page mode or EDO mode normal

access/burst access. EDO mode normal access is shown in figure 10.18, and burst access in figure

10.19.

In EDO mode, the timing for data output to the data bus in a read cycle is extended as far as the

next assertion of the

CAS signal. This delays the data latch timing by 1/2 cycle to the rising edge

of the CKIO clock, enabling the DRAM access time to be increased.

SH7708 Datasheet(PDF) 266 Page - Renesas Technology Corp