M16C28 Datasheet, PDF (288/423 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/Tiny SERIES

M16C/28 Group (M16C/28, M16C/28B)
16. MULTI-MASTER I²C bus INTERFACE
In receive mode, ACK bit = 1 WIT bit = 0
SCL
SDA
ACK-BIT bit
PIN flag
Internal WAIT flag
I²C bus interface
interrupt request signal
The writing signal of
the S00 register
7 clock
7 bit
8 clock
8 bit
ACK
clock
ACK bit
1 clock
1 bit
In receive mode, ACK bit = 1 WIT bit = 1
SCL
7 clock
8 clock
SDA
7 bit
8 bit
ACK
clock
1 bit
ACK-BIT bit
PIN flag
Internal WAIT flag
I²C bus interface
interrupt request signal
The writing signal of
the S00 register
The writing signal of the S2
0 register
1)
2)
NOTES:
1. Do not write to the I²C0 clock control register except the bit ACK-BIT.
Figure 16.12 The timing of the interrupt generation at the completion of the data receive
16.6.3 Bits 2,3 : Port Function Select Bits PED, PEC
If the ES0 bit in the S1D0 register is set to "1" (I²C bus interface enabled), the SDAMM functions as an
output port. When the PED bit is set to "1" and the SCLMM functions as an output port when the PEC bit
is set to "1". Then the setting values of P2_0 and P2_1 bits in the port P2 register are output to the I²C
bus, regardless of he internal SCL/SDA output signals. (SCL/SDA pins are onnected to I²C bus interface
circuit)
The bus data can be read by reading the port pi direction register in input mode, regardless of the setting
values of the PED and PEC bits. Table 16.5 shows the port specification.
Table 16.5 Port specifications
Pin Name
ES9 Bit
0
P20
1
1
Pin Name
ES0 Bit
0
P21
1
1
PED Bit
-
0
1
PEC Bit
-
0
1
P20 Port Direction
Register
Function
0/1
Port I/O function
-
SDA I/O function
-
SDA input function, port output function
P21 Port Direction
Register
Function
0/1
Port I/O function
-
SCL I/O function
-
SCL input function, port output funcion
Rev. 2.00 Jan. 31, 2007 ^{page 268} of 385
REJ09B0047-0200