3.14.1. Programmer's model

The wrapper is designed to enable any AHB-Lite master to connect to a standard AHB bus. This requires the wrapper to add support for the following features:

Bus ownership

When a transfer is initiated by the master, HTRANSS[1:0] is NONSEQ, the wrapper generates a request using HBUSREQM. The bus is also requested again if ownership is lost mid-burst.

Early terminated bursts

If a burst is terminated prematurely through loss of the bus, the wrapper holds the master using HREADYMUXS and rebuilds the burst when bus control is regained.

Slave responses

The slave responses of SPLIT and RETRY are handled by the wrapper. Bursts are also regenerated in these cases. ERROR responses are passed to the master through the HRESPS[1:0] signal and the master must determine an appropriate action.

Locked transfers

The HMASTLOCK signal is retimed into the arbitration phase as HLOCK. Additionally, unlocked IDLE transfers are inserted between locked bursts, as recommended in the AMBA Specification (Rev 2.0).

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