M37517F8HP Datasheet, PDF (33/98 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

7517 Group
Example of Master Transmission
An example of master transmission in the standard clock mode, at
the SCL frequency of 100 kHz and in the ACK return mode is
shown below.
(1) Set a slave address in the high-order 7 bits of the I²C address
register (address 002C16) and “0” into the RWB bit.
(2) Set the ACK return mode and SCL = 100 kHz by setting “8516”
in the I²C clock control register (address 002F16).
(3) Set “0016” in the I²C status register (address 002D16) so that
transmission/reception mode can become initializing condition.
(4) Set a communication enable status by setting “0816” in the I²C
control register (address 002E16).
(5) Confirm the bus free condition by the BB flag of the I²C status
register (address 002D16).
(6) Set the address data of the destination of transmission in the
high-order 7 bits of the I²C data shift register (address 002B16)
and set “0” in the least significant bit.
(7) Set “F016” in the I²C status register (address 002D16) to gener-
ate a START condition. At this time, a SCL for 1 byte and an
ACK clock automatically occur.
(8) Set transmit data in the I²C data shift register (address
002B16). At this time, a SCL and an ACK clock automatically oc-
cur.
(9) When transmitting control data of more than 1 byte, repeat
step (8).
(10) Set “D016” in the I²C status register (address 002D16) to gen-
erate a STOP condition if ACK is not returned from slave
reception side or transmission ends.
Example of Slave Reception
An example of slave reception in the high-speed clock mode, at
the SCL frequency of 400 kHz, in the ACK non-return mode and
using the addressing format is shown below.
(1) Set a slave address in the high-order 7 bits of the I²C address
register (address 002C16) and “0” in the RWB bit.
(2) Set the no ACK clock mode and SCL = 400 kHz by setting
“2516” in the I²C clock control register (address 002F16).
(3) Set “0016” in the I²C status register (address 002D16) so that
transmission/reception mode can become initializing condition.
(4) Set a communication enable status by setting “0816” in the I²C
control register (address 002E16).
(5) When a START condition is received, an address comparison
is performed.
(6) •When all transmitted addresses are “0” (general call):
AD0 of the I²C status register (address 002D16) is set to “1”
and an interrupt request signal occurs.
•When the transmitted addresses agree with the address set in (1):
ASS of the I²C status register (address 002D16) is set to “1”
and an interrupt request signal occurs.
• In the cases other than the above AD0 and AAS of the I²C
status register (address 002D16) are set to “0” and no inter
rupt request signal occurs.
(7) Set dummy data in the I²C data shift register (address 002B16).
(8) When receiving control data of more than 1 byte, repeat step (7).
(9) When a STOP condition is detected, the communication ends.
Rev.1.01 Aug 02, 2004 page 33 of 96