Microprocessor 8085 Buffer

The 8085 is not the originator of the incoming data therefore not to loose incoming data while the 8085 is busy with other task the data is pumped into a buffer or stack.

The data can then be retrieved and interpreted later.

The 8085 however place the data in an output latch and must receive a read confirmation before it can send more data.

On later CPUś one could access an output buffer as well which made transfers faster. Also have a look at the 8212,

It has been a long time since I used a 8085.

hi about the "latch" part.. i am not pretty sure.. but its basic function is to store the data to, be transferred till it is asked to do so ..

The ALE Address Latch Is to demultiplex the lower 8 bit address from the 8 bit data.

The 8085 has T states and each state will cause a different action. look up 8085 T states.

Because it doesn't directly handle I/O such as the 8048 does. The 48 and others have I/O pins right on the chip, whereas the 85 doesn't and everything is transferred via the Data Bus.

There are 'peripheral' chips that handle the I/O "directly" (8255?) and this CPU needs a way to get that data to and from those I/O chips.

The "buffer" and "latch" are there to ensure that the data is transferred either way - on the right 'clock cycle' and they're controlled by the 'control bus' lines. Also - when transferring data from I/O devices, those devices are dedicated and usually can 'run' faster than the CPU.