SH7641 Datasheet, PDF (409/1036 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family / SH7641 Series

Section 12 Bus State Controller (BSC)
When bank active mode is set, if only accesses to the respective banks in the area 3 space are
considered, as long as accesses to the same row address continue, the operation starts with the
cycle in figure 12.23 or 12.26, followed by repetition of the cycle in figure 12.24 or 12.27. An
access to a different area during this time has no effect. If there is an access to a different row
address in the bank active state, after this is detected the bus cycle in figure 12.24 or 12.27 is
executed instead of that in figure 12.25 or 12.28. In bank active mode, too, all banks become
inactive after a refresh cycle or after the bus is released as the result of bus arbitration.
CKIO
A25 to A0
A12/A11*¹
CSn
RASL, RASU
CASL, CASU
RD/WR
DQMxx
D31 to D0
BS
DACKn*²
Td1
Td2
Td3
Td4
Tr
Tc1
Tc2
Tc3
Tc4
Tde
Notes: 1. Address pin to be connected to pin A10 of SDRAM.
2. The waveform for DACKn is when active low is specified.
Figure 12.23 Burst Read Timing (Bank Active, Different Bank, CAS Latency 1)
Rev. 4.00 Sep. 14, 2005 Page 359 of 982
REJ09B0023-0400