Datasheet
Section 18 I
2
C Bus Interface 2 (IIC2) 
    Rev. 3.00 Mar. 15, 2006 Page 373 of 526 
   REJ09B0060-0300 
18.5 Interrupts 
There are six interrupt requests in this module; transmit data empty, transmit end, receive data full, 
NACK receive, STOP recognition, and arbitration lost/overrun error. Table 18.3 shows the 
contents of each interrupt request. 
Table 18.3  Interrupt Requests 
Interrupt Request 
Abbreviation 
Interrupt Condition 
I
2
C Mode 
Clocked 
Synchronous 
Mode 
Transmit Data Empty  TXI  (TDRE=1) 
•
 (TIE=1)  {  { 
Transmit End  TEI (TEND=1) 
•
 (TEIE=1)  {  { 
Receive Data Full  RXI (RDRF=1) 
•
 (RIE=1)  {  { 
STOP Recognition  STPI (STOP=1) 
• 
(STIE=1)  {  × 
NACK Receive  {  × 
Arbitration 
Lost/Overrun Error 
NAKI {(NACKF=1)+(AL=1)} 
•
(NAKIE=1) 
{  { 
When interrupt conditions described in table 18.3 are 1 and the I bit in CCR is 0, the CPU 
executes an interrupt exception processing. Interrupt sources should be cleared in the exception 
processing. TDRE and TEND are automatically cleared to 0 by writing the transmit data to 
ICDRT. RDRF are automatically cleared to 0 by reading ICDRR. TDRE is set to 1 again at the 
same time when transmit data is written to ICDRT. When TDRE is cleared to 0, then an excessive 
data of one byte may be transmitted. 










