TMS320VC5421 datasheet(69/104 Pages) TI1

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Electrical Specifications

December 1999 − Revised October 2008

SPRS098D

5.7

Ready Timing For Externally Generated Wait States

The following timing requirements table assumes testing over recommended operating conditions and

H = 0.5tc(CO) (see Figure 5−6 and Figure 5−7).

Table 5−10. Ready Timing Requirements for Externally Generated Wait States†

MIN

MAX

UNIT

tsu(RDY)

Setup time, READY before CLKOUT low

th(RDY)

Hold time, READY after CLKOUT low

tv(RDY)MSTRB Valid time, READY after MSTRB low‡

2H−8

th(RDY)MSTRB Hold time, READY after MSTRB low‡

† The hardware wait states can be used only in conjunction with the software wait states to extend the bus cycles. To generate wait states by READY,

at least two software wait states must be programmed. READY is not sampled until the completion of the internal software wait states.

‡ These timings are included for reference only. The critical timings for READY are those referenced to CLKOUT

MSTRB

READY

PPA[18:0]

CLKOUT

th(RDY)

th(RDY)MSTRB

tv(RDY)MSTRB

Wait State

Generated

by READY

Wait States

Generated Internally

tsu(RDY)

Figure 5−6. Memory Read With Externally Generated Wait States

TMS320VC5421 Datasheet(PDF) 69 Page - Texas Instruments