
Electrical Specifications
127
March 2004  Revised October 2004
SGUS051A
Lead
Active
Trail
DIN
td(XCOH-XZCSL)
td(XCOH-XA)
td(XCOHL-XRDL)
td(XCOHL-XZCSH)
td(XCOHL-XRDH)
WS (Synch)
XCLKOUT=XTIMCLK
XCLKOUT=1/2 XTIMCLK
XZCS0AND1, XZCS2,
XZCS6AND7
XA[0:18]
XRD
XWE
XR/W
XD[0:15]
XREADY(Synch)
NOTES: A. All XINTF accesses (lead period) begin on the rising edge of XCLKOUT. When necessary, the device will insert 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 will always hold the last address put out on the bus. This includes
alignment cycles.
D. For each sample, setup time from the beginning of the access (D) can be calculated as:
  D = (XRDLEAD + XRDACTIVE +n  1) tc(XTIM)  tsu(XRDYsynchL)XCOHL
E. Reference for the first sample is with respect to this point
  E = (XRDLEAD + XRDACTIVE)  tc(XTIM)
where n is the sample number: n = 1, 2, 3, and so forth.
th(XRDYsynchL)
tsu(XRDHsynchH)XCOHL
tsu(XRDYsynchL)XCOHL
tsu(XD)XRD
ta(XRD)
ta(A)
th(XD)XRD
th(XRDYsynchH)XZCSH
 = Don’t care. Signal can be high or low during this time.
Legend:
See Note D
See Note E
te(XRDYsynchH)
See Notes A and B
See Note C
Figure 631. Example Read With Synchronous XREADY Access
XTIMING register parameters used for this example:
XRDLEAD
XRDACTIVE
XRDTRAIL
USEREADY
X2TIMING
XWRLEAD
XWRACTIVE
XWRTRAIL
READYMODE
≥
1
3
≥
1
1
0
N/A
N/A
N/A
0 = XREADY
(Synch)
N/A = “Don’t care” for this example