via any I/O or memory-mapped port, e.g. one of the ports of an 8155. (In this way, SID can be compared to the SO ["Set Overflow"] pin of the 6502 CPU contemporary to the 8085.)

Like the 8080, the 8085 can accommodate slower memories through externally generated wait states (pin 35, READY), and has provisions for Direct Memory Access (DMA) using HOLD and HLDA signals (pins 39 and 38). An improvement over the 8080 is that the 8085 can itself drive a piezoelectric crystal