
Lead1
Active
Trail
XCLKOUT=XTIMCLK
XA[0:18]
XD[0:15]
XREADY(Synch)
td(XCOHL-XWEL)
td(XCOHL-XWEH)
td(XCOHL-XZCSH)
td(XCOH-XA)
WS(Synch)
XZCS0AND1,XZCS2,
XZCS6AND7
XRD
XWE
XR/W
td(XCOH-XZCSL)
td(XCOH-XRNWL)
td(XCOHL-XRNWH)
ten(XD)XWEL
th(XD)XWEH
tsu(XRDHsynchH)XCOHL
tsu(XRDYsynchL)XCOHL
DOUT
td(XWEL-XD
)
tdis(XD)XRNW
th(XRDYsynchL)
th(XRDYsynchH)XZCSH
=Don’tcare.Signalcanbehighorlowduringthistime.
Legend:
(F)
(E)
(A)(B)
(C)
(D)
SPRS581D – JUNE 2009 – REVISED MAY 2012
A.
All XINTF accesses (lead period) begin on the rising edge of XCLKOUT. When necessary, the device inserts an
alignment cycle before an access to meet this requirement.
B.
During alignment cycles, all signals will transition to their inactive state.
C.
During inactive cycles, the XINTF address bus always holds the last address put out on the bus except XA0, which
remains high. This includes alignment cycles.
D.
XWE1 is used in 32-bit data bus mode only. In 16-bit, this signal is XA0
E.
For each sample, setup time from the beginning of the access can be calculated as E = (XWRLEAD + XWRACTIVE +
n –1) tc(XTIM) – tsu(XRDYsynchL)XCOH where n is the sample number: n = 1, 2, 3, and so forth.
F.
Reference for the first sample is with respect to this point: F = (XWRLEAD + XWRACTIVE) tc(XTIM)
Figure 6-28. Write With Synchronous XREADY Access
XTIMING register parameters used for this example :
XRDLEAD
XRDACTIVE
XRDTRAIL
USEREADY
X2TIMING
XWRLEAD
XWRACTIVE
XWRTRAIL
READYMODE
N/A(1)
1
0
≥ 1
3
≥ 1
0 = XREADY
(Synch)
(1)
N/A = "Don't care" for this example.
Copyright 2009–2012, Texas Instruments Incorporated
Electrical Specifications
141