M16C30_02 Datasheet, PDF (124/178 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

UART2 Special Mode Register
Mitsubishi microcomputers
M16C / 30 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
P70 through P72 conforming to the simplified I ²C bus
P70/TxD2/SDA
P71/RxD2/SCL
P72/CLK2
Timer
I/O
Selector
SDDS=0
UART2 _{or DL=000}
Digital delay
(Divider)
SDDS=1 and
DL≠000
IICM=1 (SDDS=0) or
DL=000 (SDDS=1)
UART2
Analog
delay
Transmission
register
IICM=0 or
DL≠000 (SDDS=1)
SDHI
ALS
IICM=0
or IICM2=1
IICM=1
and IICM2=0
UART2 transmission/
NACK interrupt request
Noize
Filter
Noize
Filter
Noize
Filter
DQ
Arbitration
T
Timer
IICM=1
Reception register
IICM=0
or IICM2=1
UART2 reception/ACK interrupt
request
IICM=0
Start condition
detection
Stop condition
UART2
S
Q
R
Bus busy
IICM=1
and IICM2=0
detection
Falling edge
detection
L-synchronous
output enabling
bit
NACK
DQ
T
I/O
R
Q
Data bus
Selector ^{(Port P71 output data latch)}
UART2
Internal clock
IICM=1
IICM=1
SWC2
External clock
DQ
T
ACK
9th pulse
IICM=1
CLK
control
Bus collision
detection
UART2
IICM=0
Bus collision/start, stop condition
detection interrupt request
IICM=0
Falling edge of 9 bit
SWC
UART2
IICM=0
Selector
I/O
Timer
Port reading
* With IICM set to 1, the port terminal is to be readable
even if 1 is assigned to P7 1 of the direction register.
To DMA0
To DMA0
Figure 1.16.27. Functional block diagram for I²C mode
Table 1.16.9. Features in I²C mode
Function
Normal mode
1 Factor of interrupt number 10 (Note 2)
Bus collision detection
2 Factor of interrupt number 15 (Note 2)
3 Factor of interrupt number 16 (Note 2)
4 UART2 transmission output delay
5 P70 at the time when UART2 is in use
6 P71 at the time when UART2 is in use
7 P72 at the time when UART2 is in use
UART2 transmission
UART2 reception
Not delayed
TxD2 (output)
RxD2 (input)
CLK2
8 Noise filter width
9 Reading P71
15ns
Reading the terminal when 0 is
assigned to the direction register
10 Initial value of UART2 output
H level (when 0 is assigned to
the CLK polarity select bit)
Note 1: Make the settings given below when I²C mode is in use.
Set 0 1 0 in bits 2, 1, 0 of the UART2 transmission/reception mode register.
Disable the RTS/CTS function. Choose the MSB First function.
Note 2: Follow the steps given below to switch from a factor to another.
1. Disable the interrupt of the corresponding number.
2. Switch from a factor to another.
3. Reset the interrupt request flag of the corresponding number.
4. Set an interrupt level of the corresponding number.
Note 3: Set an initial value of SDA transmission output when serial I/O is invalid.
I²C mode (Note 1)
Start condition detection or stop
condition detection
No acknowledgment detection (NACK)
Acknowledgment detection (ACK)
Delayed
SDA (input/output) (Note 3)
SCL (input/output)
P72
50ns
Reading the terminal regardless of the
value of the direction register
The value set in latch P70 when the port is
selected
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