What are some application scenarios of APB4? Please brief me about this as I am working on APB4.
APB is typically used to access peripheral registers within a slave.
The advantages of APB is that it is very simple to implement, has a low wire count and APB4 should support all the features needed for a register access use case, such as security, error signalling and strobes.
The downside of APB is that it is inherently low performance, as it requires at least 2 cycles per access and only supports one outstanding transactions. Therefore, you would typically only convert to APB near to the slave, and keep the rest of the network in a higher performance protocol.