RX62N Datasheet, PDF (5/25 Pages) Renesas Technology Corp – 100 MHz 32-bit RX MCU with FPU, 165 DMIPS, up to 512-Kbyte Flash, Ethernet, USB 2.0

RX62N Group and RX621 Group
16-Bit SDRAM Connection and Access Examples
Table 3 SDRAM Initialization Auto Refresh Control Register (SDIR)
Bit Name
Initialization auto refresh period bits
(ARFI[3:0])
Initialization auto refresh count bits
(ARFC[3:0])
Initialization precharge cycle count setting bits
(PRC[2:0])
Setting Value
0001b
0010b
000b
Function
4 cycles
2 times
3 cycles
Initialization
precharge cycle
Initialization auto refresh
cycle
Initialization auto refresh
cycle
SDCLK
SDRAM command PRA DSL DSL RFA DSL DSL DSL RFA DSL DSL DSL
SDIR.PRC: "000" = 3 cycles
SDIR.ARFI: "0001" = 4 cycles
SDIR.ARFC: "0010" = 2 times
DSL: Device deselect command
RFA: Auto refresh command
PRA: All bank precharge command
Figure 2 Initialization Sequence Timing
R01AN0585EJ0202 Rev.2.02
Feb 14, 2014
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