UPD78F1502AGK-GAK-AX Datasheet, PDF (569/1031 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcontrollers

78K0R/Lx3
CHAPTER 14 SERIAL ARRAY UNIT
Simplified I²C (IIC10, IIC20) performs the following four types of communication operations.
• Address field transmission (See 14.7.1.)
• Data transmission
(See 14.7.2.)
• Data reception
(See 14.7.3.)
• Stop condition generation (See 14.7.4.)
14.7.1 Address field transmission
Address field transmission is a transmission operation that first executes in I²C communication to identify the target for
transfer (slave). After a start condition is generated, an address (7 bits) and a transfer direction (1 bit) are transmitted in
one frame.
Simplified I²C
IIC10
IIC20
Target channel
Pins used
Channel 2 of SAU0
SCL10, SDA10 ^Note
Channel 0 of SAU1
SCL20, SDA20 ^Note
Interrupt
INTIIC10
INTIIC20
Transfer end interrupt only (Setting the buffer empty interrupt is prohibited.)
Error detection flag Parity error detection flag (PEFmn)
Transfer data length
8 bits (transmitted with specifying the higher 7 bits as address and the least significant bit as R/W
control)
Transfer rate
Max. fCLK/4 [MHz] (SDRmn [15:9] = 1 or more)
fCLK: System clock frequency
However, the following condition must be satisfied in each mode of I²C.
• Max. 400 kHz (first mode)
• Max. 100 kHz (standard mode)
Data level
Forward output (default: high level)
Parity bit
No parity bit
Stop bit
Appending 1 bit (for ACK reception timing)
Data direction
MSB first
Note To perform communication via simplified I²C, set the data I/O pins (SDA10, SDA20) in the N-ch open-drain output
(VDD tolerance) mode (POM14 = 1, POM11 = 1) by using the port output mode register 1 (POM1) (see 4.3
Registers Controlling Port Function for details). When communicating with an external device with a different
potential, set the N-ch open-drain output (VDD tolerance) mode (POM15 = 1, POM10 = 1) also for the clock
input/output pins (SCL10, SCL20) (see 4.4.4 Connecting to external device with different potential (2.5 V, 3 V)
for details).
Remark m: Unit number (m = 0, 1), n: Channel number (n = 0, 2)
R01UH0004EJ0501 Rev.5.01
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Jun 20, 2011