I have the following doubts in AMBA 3 APB v1.0
1) How the APB slave generate PREADY is high /low?
2)What are all the factors APB slave have to consider while generating the PREADY is high /zero? Eg) PSELx, PENABLE, states etc
3) in figure 2-2,During the right transfer with wait states ,PSELx and PENABLE is high PREADY is low for 2 clock period. Why PREADY is low for 2 clock ? (ref Figure 2-2 Write transfer with wait states)
4)how to check the write /read transfer with wait states on simulation ?
5)in access state at what condition PREADY will be low ?
Apologies - I've noticed the first IF statement in #4 wasn't correct so I've corrected
if (PSEL == 1'b1 && PENABLE == 1'b1) begin
if (PSEL == 1'b1 && PENABLE == 1'b1 && PREADY == 1'b0) begin
My original post has been corrected, too.
Thank you Toshihisa Oishi .Now i understood . IHI 0024C AMBA® APB ProtocolVersion: 2.0 gives more clarity about PREADY signal .
Thank you Dheeran for the feedback. It's useful information that v2.0 give more clarity about PREADY signal.Just for future reference for other people in Community, below is the link to AMBA APB Protocol Specification Version 2.0 (aka Version C).