M16C30_02 Datasheet, PDF (128/178 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

UART2 Special Mode Register 2
Mitsubishi microcomputers
M16C / 30 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Bit 0 of the UART2 special mode register 2 (address 037616) is used as the I²C mode select bit 2. Table
1.16.11 shows the types of control to be changed by I²C mode select bit 2 when the I²C mode select bit
is set to “1”. Table 1.16.12 shows the timing characteristics of detecting the start condition and the stop
condition. Set the start/stop condition control bit (bit 7 of UART2 special mode register 2) to “1” in I²C
mode.
Table 1.16.11. Functions changed by I²C mode select bit 2
Function
IICM2 = 0
IICM2 = 1
1 Factor of interrupt number 15
2 Factor of interrupt number 16
No acknowledgment detection (NACK) UART2 transmission (the rising edge
of the final bit of the clock)
Acknowledgment detection (ACK)
UART2 reception (the falling edge
of the final bit of the clock)
3 Timing for transferring data from the The rising edge of the final bit of the
UART2 reception shift register to the reception clock
reception buffer.
The falling edge of the final bit of the
reception clock
4 Timing for generating a UART2
reception/ACK interrupt request
The rising edge of the final bit of the
reception clock
The falling edge of the final bit of the
reception clock
Table 1.16.12. Timing characteristics of detecting the start condition and the stop condition (Note 1)
3 to 6 cycles < duration for setting-up (Note 2)
3 to 6 cycles < duration for holding (Note 2)
Note 1 : When the start/stop condition control bit SHTC is “1” .
Note 2 : “Cycles” is in terms of the input oscillation frequency f(XIN) of the main clock.
SCL
SDA
(Start condition)
SDA
(Stop condition)
Duration for
setting up
Duration for
holding
127