E202075_HD404889 Datasheet, PDF (113/202 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

HD404889/HD404899/HD404878/HD404868 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, and a multiplexer are also configured for the serial interface as follows.
• Serial data register (SRL: $026, SRU: $027)
• Serial mode register 1 (SMR1: $024)
• Serial mode register 2 (SMR2: $025)
• Port mode register 3 (PMR3: $00B)
• Octal counter (OC)
• Selector
The block diagram of the serial interface is shown in figure 62.
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