Chapter 11 Serial Interface Function; Overview; 3-Wire Serial I/O (Csi0, Csi2, Csi3): 8 Bits - NEC Renesas V850/SC1 User Manual

11.1 Overview

The V850/SC1, V850/SC2, and V850/SC3 incorporate the following serial interfaces.
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Channel 0: 3-wire serial I/O (CSI0)/I
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Channel 2: 3-wire serial I/O (CSI2)/I
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Channel 3: 3-wire serial I/O (CSI3)/asynchronous serial interface (UART1)
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Channel 4: 3-wire serial I/O (CSI4)/asynchronous serial interface (UART0)
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Channel 5: 3-wire serial I/O (CSI5)
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Channel 6: 3-wire serial I/O (CSI6)
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Channel 7: Asynchronous serial interface (UART2)
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Channel 8: Asynchronous serial interface (UART3)
2 2
Note I C0 and I C1 support multimasters.
Either 3-wire serial I/O or I

11.2 3-Wire Serial I/O (CSI0, CSI2, CSI3): 8 Bits

CSIn (n = 0, 2, 3) has the following two modes.
(1) Operation stopped mode
This mode is used when serial transfers are not performed.
(2) 3-wire serial I/O mode (fixed as MSB first)
This is an 8-bit data transfer mode using three lines: a serial clock line (SCKn), a serial output line (SOn), and a
serial input line (SIn).
Since data can be transmitted and received simultaneously in 3-wire serial I/O mode, the processing time for
data transfer is reduced.
The first bit in the 8-bit data in serial transfers is fixed as the MSB.
The SCK0 and SCK2 pins can be used to select normal output and N-ch open-drain output, respectively, by
setting the port 1 function register and port 2 function register (PF1, PF2).
3-wire serial I/O mode is useful for connection to devices such as peripheral I/O that include a clocked serial
interface, and display controllers.
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CHAPTER 11 SERIAL INTERFACE FUNCTION
2 Note
C0
2 Note
C1
2
C can be used as a serial interface.
User's Manual U15109EJ3V0UD