CHAPTER 5. PERIPHERAL HARDWARE FUNCTIONS

5.5SERIAL INTERFACE

5.5.1Serial Interface Functions

The μPD75402A incorporates a clocked 8-bit serial interface, with the following three modes available.

(1) Operation-halted mode

This mode is used when no serial transfer is to be performed, and allows power dissipation to be reduced.

(2) 3-wire serial I/O mode

In this mode, 8-bit data transfer is performed using three lines: The serial clock (SCK), serial output (SO), and serial input (SI).

In the 3-wire serial I/O mode simultaneous transmission and reception is possible, increasing the data transfer processing speed.

The 3-wire serial I/O mode allows connection to 75X series and 78K series devices and various peripheral I/O devices.

Serial data transfer is performed MSB-first.

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NEC PD75402A, PD75P402 Peripheral Hardware Functions Serial Interface, Serial Interface Functions, Operation-halted mode