SL811HS

DMA Write Cycle

nDRQ

nDACK

tdakrqtackrq

tdack

tdwrlo

D0-D7

 

 

 

 

DATA

 

tdsu

 

 

 

 

 

 

tdwrp

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

nW R

DMA Write Cycle

SL811 DMA W RITE CYCLE TIMING

tdhld

tackwrh

Parameter

Description

Min.

Typ.

Max.

 

 

 

 

 

tdack

nDACK low

80 ns

 

 

 

 

 

 

 

tdwrlo

nDACK to nWR low delay

5 ns

 

 

 

 

 

 

 

tdakrq

nDACK low to nDRQ high delay

5 ns

 

 

 

 

 

 

 

tdwrp

nWR pulse width

65 ns

 

 

 

 

 

 

 

tdhld

Data hold after nWR high

5 ns

 

 

 

 

 

 

 

tdsu

Data set-up to nWR strobe low

60 ns

 

 

 

 

 

 

 

tackrq

NDACK high to nDRQ low

5 ns

 

 

 

 

 

 

 

tackwrh

NDACK high to nDRQ low

5 ns

 

 

 

 

 

 

 

twrcycle

DMA Write Cycle Time

150 ns

 

 

 

 

 

 

 

Note nWR must go low after nDACK goes low in order for nDRQ to clear. If this sequence is not implemented as requested, the next nDRQ is not inserted.

Document 38-08008 Rev. *D

Page 28 of 32

Page 28
Image 28
Cypress SL811HS manual DMA Write Cycle