DDR4 SDRAM computer buses have migrated towards replacing parallel buses with serial buses, for example by the evolution of Serial ATA replacing Parallel ATA, PCI Express replacing PCI, and serial ports replacing parallel ports. In general, serial buses are easier to scale up and have fewer wires/traces, making circuit boards using them easier to design. In the longer term, experts speculate that non-volatile RAM types like PCM (phase-change memory), RRAM (resistive random-access memory), or MRAM (magnetoresistive random-access memory) could replace DDR4 SDRAM and its successors. GDDR5 SGRAM is a graphics type of DDR3 synchronous graphics RAM, which was introduced before DDR4, and
Serial port serial ports in a PC. The only limitation is the amount of resources, such as operating memory and computing power, needed to emulate many serial ports at the same time. Virtual serial ports emulate all hardware serial port functionality, including baud rate, data bits, parity bits, stop bits, etc. Additionally, they allow controlling the data flow, emulating all signal lines (DTR, DSR, CTS, RTS, DCD, and RI) and customizing pinout. Virtual serial ports are common with Bluetooth and are the standard way of receiving data from Bluetooth-equipped GPS modules. Virtual serial port emulation can be useful in case there is