HD404849 Datasheet, PDF (81/127 Pages) Hitachi Semiconductor – 4-Bit Single-Chip Microcomputer

HD404849 Series
Serial Interface
The serial interface serially transfers and receives 8-bit data, and includes the following features.
• Multiple transmit clock sources
 External clock
 Internal prescaler output clock
 System clock
• Output level control in idle states
Five registers, an octal counter are also configured for the serial interface as follows.
 Serial data register (SRL: $006, SRU: $007)
 Serial mode register A (SMRA: $005)
 Serial mode register B (SMRB: $028)
 Port mode register A (PMRA: $004)
 Miscellaneous register (MIS: $00C)
 Octal counter (OC)
 Selector
The block diagram of the serial interface is shown in figure 66.
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