Renesas H8S/2111B Network Card User Manual


 
IFIIC60B_010020040200 Rev. 1.00, 05/04, page 277 of 544
Section 13 I
2
C Bus Interface (IIC)
This LSI has a two-channel I
2
C bus interface. The I
2
C bus interface conforms to and provides a
subset of the Philips I
2
C bus (inter-IC bus) interface functions. The register configuration that
controls the I
2
C bus differs partly from the Philips configuration, however.
13.1 Features
Selection of addressing format or non-addressing format
I
2
C bus format: addressing format with an acknowledge bit, for master/slave operation
Clocked synchronous serial format: non-addressing format without an acknowledge bit, for
master operation only
Conforms to Philips I
2
C bus interface (I
2
C bus format)
Two ways of setting slave address (I
2
C bus format)
Start and stop conditions generated automatically in master mode (I
2
C bus format)
Selection of the acknowledge output level in reception (I
2
C bus format)
Automatic loading of an acknowledge bit in transmission (I
2
C bus format)
Wait function in master mode (I
2
C bus format)
A wait can be inserted by driving the SCL pin low after data transfer, excluding
acknowledgement.
The wait can be cleared by clearing the interrupt flag.
Wait function (I
2
C bus format)
A wait request can be generated by driving the SCL pin low after data transfer.
The wait request is cleared when the next transfer becomes possible.
Interrupt sources
Data transfer end (including when a transition to transmit mode with I
2
C bus format occurs,
when ICDR data is transferred, or during a wait state)
Address match: When any slave address matches or the general call address is received in
slave receive mode with I
2
C bus format (including address reception after loss of master
arbitration)
Start condition detection (in master mode)
Stop condition detection (in slave mode)
Selection of 16 internal clocks (in master mode)
Direct bus drive (SCL/SDA pin)
Eight pins—P52/SCL0, P97/SDA0, P86/SCL1, P42/SDA1, PG4/ExSDAA, PG5/ExSCLA,
PG6/ExSDAB, and PG7/ExSCLB—(normally NMOS push-pull outputs) function as
NMOS open-drain outputs when the bus drive function is selected.