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Geode GXLV Processor Series Low Power Integrated x86 Solutions

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<strong>Geode</strong> <strong>GXLV</strong> <strong>Processor</strong> <strong>Series</strong>Electrical Specifications (Continued)Table 6-17. SDRAM Interface Signals (Refer to Figures 6-9 and 6-10)Symbol Parameter Min Max Unitt1RASA#, RASB#, CASA#, CASB#,WEA#, WEB#, CKEA, CKEB,DQM[7:0], CS[3:0]# Ouput Valid fromSDCLK[3:0]t1Min=z–1.5 t1Max=z–1.0 nst2 MA[12:0], BA[1:0] Output Valid from t2Min=z–1.7 t2Max=z–1.2 nsSDCLK[3:0]t3 MD[63:0] Output Valid fromt2Min=z–1.6 t3Max=z–0.3 nsSDCLK[3:0]t4 MD[63:0] Read Data in Setup to0 nsSDCLK_INt5 MD[63:0] Read Data Hold to2.0 nsSDCLK_INCalculation of minimum and maximum values of t1, t2, and t3: (seeFigure4-10onpage124)x =shift value applied to SHFTSDCLK field where SHFTSDCLK field = GX_BASE+8404h[5:3].y=coreclockperiod÷2z=(x*y)Equation Example:A 200 MHz <strong>GXLV</strong> processor interfacing with a 66 MHz SDRAM bus, having a shift value of 2:x=2core clock period = 1/(200 MHz) = 5 nsy=5÷2t1Min=(2*(5÷2))–1.5=3.5nst1 Max = (2 * (5 ÷ 2)) – 1.0 = 4.0 nst1, t2, t3SDCLK[3:0]CNTRL, MA[12:0],BA[1:0], MD[63:0]ValidFigure 6-9. Output Valid Timingt4t5SDCLK_INMD[63:0]Read Data InData ValidData ValidFigure 6-10. Setup and Hold Timings - Read Data Inwww.national.com 202 Revision 1.3

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