M16C62A Datasheet, PDF (117/242 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

UART2 Special Mode Register
Mitsubishi microcomputers
M16C / 62A Group (80-pin)
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
P70 through P72 conforming to the simplified I ²C bus
P70/TxD2/SDA
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
Transmission
delay
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
P71/RxD2/SCL
Noize
Filter
Noize
Filter
Noize
Filter
DQ
Arbitration
T
Timer
IICM=1
Reception register
IICM=0
or IICM2=1
UART2 reception/ACK interrupt
request, DMA1 request
IICM=0
Start condition
detection
Stop condition
detection
UART2
S
Q Bus busy
R
L-synchronous
DQ
Falling edge
output enabling
T
detection
bit
IICM=1
and IICM2=0
NACK
Selector
I/O
R
Q
Data bus
(Port P71 output data latch)
UART2
Internal clock
DQ
T
ACK
9th pulse
IICM=1
IICM=1
IICM=1
SWC2 _CLK
Bus collision
detection
control
External clock
UART2
IICM=0
Bus collision/start, stop condition
detection interrupt request
IICM=0
Falling edge of 9 bit
SWC
P72/CLK2
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.
Note: P72/CLK2 is not connected to the outside.
Figure 1.14.26. Functional block diagram for I²C mode
To DMA0, DMA1
To DMA0
Table 1.14.9. Features in I²C mode
Function
1 Factor of interrupt number 10 (Note 2)
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
DMA1 factor at the time when 1 1 0 1 is assigned
to the DMA request factor selection bits
8 Noise filter width
9 Reading P71
10 Initial value of UART2 output
Normal mode
Bus collision detection
UART2 transmission
UART2 reception
Not delayed
TxD2 (output)
RxD2 (input)
UART2 reception
15ns
Reading the terminal when 0 is
assigned to the direction register
H level (when 0 is assigned to
the CLK polarity select bit)
I²C mode (Note 1)
Start condition detection or stop
condition detection
No acknowledgment detection (NACK)
Acknowledgment detection (ACK)
Delayed (digital or analog delay can be selected)
SDA (input/output) (Note 3)
SCL (input/output)
Acknowledgment detection (ACK)
50ns
Reading the terminal regardless of the
value of the direction register
The value set in latch P70 when the port is
selected
Note 1: Make the settings given below when I²C mode is in use.
Set “0 1 0 2” in bits 2, 1, and 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.
116