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CHAPTER 13
SERIAL INTERFACE SIO0
User’s Manual U12790EJ2V0UD
(4) Interrupt timing specification register 0 (SINT0)
This register sets the bus release interrupt and address mask functions and displays the P27/SCK0/SCL pin
level status.
SINT0 is set by a 1-bit or 8-bit memory manipulation instruction.
Reset input sets SINT0 to 00H.
Figure 13-7. Format of Interrupt Timing Specification Register 0 (SINT0) (1/2)
Notes 1. Bit 6 (CLD) is a read-only bit.
2. When not using the I2C mode, set CLC to 0.
Used in I2C bus mode.
SCL pin enters high-impedance state unless serial transfer is being performed (except for clock line,
which is kept high).
Used to enable master device to generate start condition and stop condition signals.
<6>
<5>
<4>
<3>
<2>
1
0
7
Symbol
SINT0
0
CLD
SIC
SVAM CLC WREL WAT1 WAT0
FF63H
00H
R/WNote 1
Address
After reset
R/W
WREL
0
Wait state has already been cancelled.
Cancel wait state. Automatically cleared to 0 when the state is cancelled.
(Used to cancel wait state by means of WAT0 and WAT1.)
CLC
0
1
Control of clock levelNote 2
Used in I2C bus mode.
Output level of SCL pin made low unless serial transfer is being performed.
R/W
1
Control of wait sate cancellation
R/W
WAT1
0
1
Control of wait and interrupt
Interrupt servicing request generated at rising edge of 8th SCK0 clock
(keeping clock output in high impedance state).
R/W
WAT0
0
Used in I2C bus mode (8-clock wait).
Interrupt servicing request generated at rising edge of 8th SCL clock.
(In the case of a master device, SCL output is made low to enter a wait state after 8 clock pulses are
output. In the case of a slave device, SCL output is made low to request a wait state after 8 clock
pulses are input.)
1
Used in I2C bus mode (9-clock wait).
Interrupt servicing request generated at rising edge of 9th SCL clock .
(In the case of a master device, SCL output is made low to enter a wait state after 9 clock pulses are
output. In the case of a slave device, SCL output is made low to request a wait state after
9 clock pulses are input.)
0
Setting prohibited
1