M37221M4H_15 Datasheet, PDF (43/114 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER

M37221M4H/M6H/M8H/MAH–XXXSP/FP M37221EASP/FP
8.6.10 Example of Master Transmission
An example of master transmission in the standard clock mode, at
the SCL frequency of 100 kHz with the ACK return mode enable, is
shown below.
➀ Set a slave address in the high-order 7 bits of the I²C address
register (address 00D816) and “0” in the RBW bit.
➁ Set the ACK return mode and SCL = 100 kHz by setting “8516” in
the I²C clock control register (address 00DB16).
➂ Set “1016” in the I²C status register (address 00D916) and hold the
SCL at HIGH.
④ Set a communication enable status by setting “4816” in the I²C
control register (address 00DA16).
➄ Set the address data of the destination of transmission in the high-
order 7 bits of the I²C data shift register (address 00D716) and set
“0” in the least significant bit.
⑥ Set “F016” in the I²C status register (address 00D916) to generate
a START condition. At this time, an SCL for 1 byte and an ACK
clock automatically occurs.
⑦ Set transmit data in the I²C data shift register (address 00D716). At
this time, an SCL and an ACK clock automatically occurs.
➇ When transmitting control data of more than 1 byte, repeat step ➆.
➈ Set “D016” in the I²C status register (address 00D916). After this, if
ACK is not returned or transmission ends, a STOP condition will
be generated.
8.6.11 Example of Slave Reception
An example of slave reception in the high-speed clock mode, at the
SCL frequency of 400 kHz, with the ACK non-return mode enabled
while using the addressing format, is shown below.
➀ Set a slave address in the high-order 7 bits of the I²C address
register (address 00D816) and “0” in the RBW bit.
➁ Set the ACK non-return mode and SCL = 400 kHz by setting “2516”
in the I²C clock control register (address 00DB16).
➂ Set “1016” in the I²C status register (address 00D916) and hold the
SCL at HIGH.
④ Set a communication enable status by setting “4816” in the I²C
control register (address 00DA16).
➄ When a START condition is received, an address comparison is
executed.
⑥ •When all transmitted address are“0” (general call):
AD0 of the I²C status register (address 00D916) is set to “1” and
an interrupt request signal occurs.
•When the transmitted addresses match the address set in ➀:
ASS of the I²C status register (address 00D916) 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 00D916) are set
to “0” and no interrupt request signal occurs.
⑦ Set dummy data in the I²C data shift register (address 00D716).
➇ When receiving control data of more than 1 byte, repeat step ➆.
➈ When a STOP condition is detected, the communication ends.
Rev.1.00 Oct 01, 2002 page 41 of 110
REJ03B0134-0100Z