TI380C25 Datasheet, PDF (41/71 Pages) Texas Instruments – TOKEN-RING COMMPROCESSOR

SCS, SRSX,
SRS0 – SRS2,
SBHE
SRAS
256
Valid
264
265
266a
267
Valid ^†
TI380C25
TOKEN-RING COMMPROCESSOR
SPWS012 – JANUARY 1995
268
SIACK
272a
273a
SWR
272a
273a
SRD
SDDIR
High
SDBEN
272a
282R
283R
273a
286
279
282a
275
SRDY ^‡
Hi-Z
255
Hi-Z
SADH0 – SADH7,
259
SADL0 – SADL7,
SPH, SPL ^§
Hi-Z
260
261
261a
Output Data Valid
Hi-Z
† _{In 80x8x mode, SRAS can be used to strobe the values of SBHE, SRSX, SRS0 – SRS2, and SCS. When used to do so, SRAS must meet}
parameter 266a, and SBHE, SRS0 – SRS2, and SCS must meet parameter 264. If SRAS is strapped high, parameters 266a and 264 are
irrelevant and parameter 268 must be met.
‡ _{When the TMS380C25 begins to drive SDBEN inactive, it has already latched the write data internally. Parameter 263 must be met to the input}
of the data buffers.
§ _{In 8-bit 80x8x mode DIO reads, the SADH0 – SADH7 contain don’t care data.}
Figure 14. 80x8x DIO Read-Cycle Timing
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