HD6412373R RENESAS [Renesas Technology Corp], HD6412373R Datasheet - Page 306

• Manufacturer Part Number: HD6412373R
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 6 Bus Controller (BSC)
In some synchronous DRAMs provided with a self-refresh mode, the interval between clearing
self-refreshing and the next command is specified. A setting can be made in bits TPCS2 to TPCS0
in REFCR to make the precharge time after self-refreshing from 1 to 7 states longer than the
normal precharge time. In this case, too, normal precharging is performed according to the setting
of bits TPC1 and TPC0 in DRACCR, and therefore a setting should be made to give the optimum
post-self-refresh precharge time, including this time. Figure 6.58 shows an example of the timing
when the precharge time after self-refreshing is extended by 2 states.
Rev.7.00 Mar. 18, 2009 page 238 of 1136
REJ09B0109-0700
Precharge-sel
Address bus
SDRAMφ
CAS
RAS
CKE
WE
(TPC1 = 1, TPC0 = 0, RCW1 = 0, RCW0 = 0, RLW1 = 0, RLW0 = 0)
φ
PALL
T
Rp
SELF
Figure 6.57 Self-Refresh Timing
T
Rr
Software standby
NOP
T
Rc2