Renesas 16-bit single-chip microcomputer 用户手册

Rev.1.02 Jul 01, 2005 page 136 of 314
REJ09B0126-0102

M16C/6N Group (M16C/6NL, M16C/6NN)

14. Serial I/O

Under development

This document is under development and its contents are subject to change.

Table 14.3 lists the functions of the input/output pins during clock synchronous serial I/O mode. Table

14.3 shows pin functions for the case where the multiple transfer clock output pin select function is

deselected. Table 14.4 lists the P6_4 pin functions during clock synchronous serial I/O mode.

Note that for a period from when the UARTi operation mode is selected to when transfer starts, the TXDi

pin outputs an “H”.

Figure 14.11 shows the transmit/receive timings during clock synchronous serial I/O mode.

Table 14.3 Pin Functions (When Not Select Multiple Transfer Clock Output Pin Function)

i = 0 to 2

Table 14.4 P6_4 Pin Functions

TXDi

(P6_3, P6_7, P7_0)

RXDi

(P6_2, P6_6, P7_1)

CLKi

(P6_1, P6_5, P7_2)

_________ ________

CTSi/RTSi

(P6_0, P6_4, P7_3)

Pin Name

Function

Method of Selection

Serial Data Output

Serial Data Input

Transfer Clock Output

Transfer Clock Input

________

CTS Input

________

RTS Output

I/O Port

(Outputs dummy data when performing reception only)

PD6_2 and PD6_6 bits in PD6 register = 0

PD7_1 bit in PD7 register = 0

(Can be used as an input port when performing transmission only)

CKDIR bit in UiMR register = 0

CKDIR bit = 1

PD6_1 and PD6_5 bits in PD6 register = 0

PD7_2 bit in PD7 register = 0

CRD bit in UiC0 register = 0

CRS bit in UiC0 register = 0

PD6_0 and PD6_4 bits in PD6 register = 0

PD7_3 bit in PD7 register = 0

CRD bit = 0

CRS bit = 1

CRD bit = 1

-: “0” or “1”

NOTES:

__________ __________

In addition to this, set the CRD bit in the U0C0 register to “0” (CTS0/RTS0 enabled) and the CRS

__________

bit in the U0C0 register to “1” (RTS0 selected).

2. When the CLKMD1 bit = 1 and the CLKMD0 bit = 0, the following logic levels are output:

• High if the CLKPOL bit in the U1C0 register = 0

• Low if the CLKPOL bit = 1

Bit set Value

Pin Function

U1C0 Register

UCON Register

PD6 Register

CRD bit

CRS bit

RCSP bit CLKMD1 bit CLKMD0 bit

PD6_4 bit

P6_4

Input: 0, Output: 1

_________

CTS1

_________

RTS1

_________

CTS0

(1)

CLKS1

(2)