NEXT (Basic Bus: One initiator.)
I/O Blocks, Common Interface Nets.
will consider a number of I/O blocks. All will be targets, most will also generate interrupts and some will also be initiators.
We use no bi-directional (tri-state) busses within our SoC: instead we use dedicated busses
and multiplexor trees.
We use the following RTL net names:
- addr Internal address selection within a target,
- hwen Asserted during a target write,
- hren Asserted during a target read,
- wdata Input data to a target when written,
- rdata Output data when target is read,
- interrupt Asserted by target when wanting attention.
On an initiator the net directions will be reversed.