Data Transfer Cycle States

[okubohitoshi]

I cannot understand the relations of FB_TA and the state of the bus cycle.

When auto-acknowledge disable ( AA = 0 ) ,

does it continue the current state (S1) until FB_TA becomes Low ?

If FB_TA becomes Low, is it changed by the next state (S2) ?

[Kan_Li · Accepted solution]

Hi,

Yes, your understanding is correct.

If FB_TA is recognized asserted(driven low internally or externally), then the cycle moves on to S2. If FB_TA is not asserted internally or externally, then the S1 state continues to repeat.

Hope that makes sense,

B.R

Kan

[okubohitoshi]

Thank you for answer.

Another one point let me ask you a question.

Is the following description a mistake?

in "Freescale Semiconductor Document Number: AN4393 Application Note Rev. 0, 05/2012"

2.1 Read cycle

4.

"If the auto-acknowledge feature is disabled (CSCRn[AA] = 0), then FB_TA must be negated 13.5 ns (FB4) before the third cycle."

[Kan_Li]

Hi ,

I think the above description means if you want to put the FlexBus into next stage, FB_TA must be negated 13.5 ns (FB4) before the third cycle when auto-acknowledge feature is disabled.

Hope that makes sense,

B.R

Kan

[okubohitoshi]

Thank you for your answer.