HD6432670 Hitachi, HD6432670 Datasheet - Page 262

• Manufacturer Part Number: HD6432670
• Description: (HD64F267x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

T
T
T
T
T
T
Rp1
Rp2
Rrw
Rr
Rc1
Rc2
ø
SDRAMø
Address bus
Precharge-sel
CKE
High
PALL
NOP
REF
NOP
Figure 6.55 Auto Refresh Timing
(TPC = 1, TPC0 = 1, RCW1 = 0, RCW0 = 1)
When the interval specification from the REF command to the ACTV cannot be satisfied, setting
the RLW1 and RLW0 bits of REFCR enables one to three wait states to be inserted in the refresh
cycle. Set the optimum number of waits according to the synchronous DRAM connected and the
operating frequency of this LSI. Figure 6.56 shows the timing when one wait state is inserted.
Rev. 2.0, 04/02, page 216 of 906