CY7C421-25PI 参数 Datasheet PDF下载

CY7C419/21/25/29/33

Switching Waveforms

(continued)

Figure 7. Last Write to First Read Full Flag

LAST WRITE

FIRST READ

ADDITIONAL

READS

FIRST WRITE

R

W

t

WFF

FF

t

RFF

Figure 8. Last Read to First Write Empty Flag

W

LAST READ

FIRST WRITE

ADDITIONAL

WRITES

FIRST READ

R

t

REF

EF

t

A

DATA OUT

VALID

VALID

t

WEF

Figure 9. Retransmit

t

RTC

FL/RT

t

PRT

R,W

t

RTR

Notes

13. EF, HF and FF may change state during retransmit as a result of the offset of the read and write pointers, but flags will be valid at t

RTC

.

14. t

RTC

= t

PRT

+ t

RTR

.

Document #: 38-06001 Rev. *C

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