HD6417144 RENESAS [Renesas Technology Corp], HD6417144 Datasheet - Page 536

• Manufacturer Part Number: HD6417144
• Description: 32-Bit RISC Microcomputer SuperHTM RISC engine Family/SH7144 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

14. I
14.3.8
The ICDRE flag is set and cleared under the conditions as shown below. Since the ICDRE flag is
an internal flag, it cannot be accessed.
Rev.4.00 Mar. 27, 2008 Page 492 of 882
REJ09B0108-0400
Bit Name
ICDRE
2
C Bus Interface (IIC) Option
ICDRE Flag (Internal Flag)
0
Initial Value
Description
Transmit Data Write Request Flag
This flag is an internal flag that indicates the ICDR (ICDRT) state in
transmission mode.
0: Indicates that the data to be transmitted has been already written to
1: Indicates that data has been transferred from ICDRT to ICDRS and
[Setting conditions]
•
•
[Clearing conditions]
•
•
•
Note that if the ACKE bit is set to 1 in I
acknowledge bit decision, ICDRE is not set when data transmission is
completed while the acknowledge bit is 1.
Due to the set condition B above, ICDRE is temporarily cleared to 0
when data is written to ICDR (ICDRT); however, since data is
transferred from ICDRT to ICDRS immediately, ICDRE is set to 1
again. Do not write data to ICDR when TRS = 0 because the ICDRE
flag value is invalid during the time.
ICDR (ICDRT) or ICDR is initialized.
is being transmitted, or the start condition has been detected or
transmission has been completed, thus allowing the next data to be
written to.
When the start condition is detected from the bus line state in I
bus format or serial format.
When data is transferred from ICDRT to ICDRS.
A. When data transmission is completed while ICDRE =0 (at the
B. When ICDR is written to in transmit mode after data
When transmit data is written to ICDR (ICDRT).
When the stop condition is detected in I
format.
When 0 is written to the ICE bit.
rising edge of the 9th cycle of the clock).
transmission is completed while ICDRE = 1.
2
C bus format thus enabling
2
C bus format or serial
2
C