AHB revisions from AHB3 to AHB5

I noticed that "Multi slave select" is one of the new features in AHB5.

But, isn't it possible to set multiple slaves in a system with a decoder and a multiplexor?

I think we can do that with AHB3.

What is the major difference between AHB3 and AHB5 about  "Multi slave select"?

  • In AHB5 what "multi slave select" is describing is where one physical slave can have multiple HSEL inputs, allowing the system address decoder to tell the slave which area of the slave is being addressed, perhaps simplifying the address decode logic inside the slave. So you could have one HSEL input on your slave for configuration registers, and another HSEL input to access a data array, with each address range possibly at different ends of the system address map.

    All AHB specifications support multiple separate slaves on the bus (as you described with a decoder and multiplexor), so what AHB5 is adding is a documented way of having what looks like multiple separate slaves with different HSEL inputs all sharing a common set of AHB control signals (HADDR, HTRANS, HWRITE etc).