CHAPTER 10 SERIAL INTERFACE FUNCTION
User’s Manual U13850EJ6V0UD
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Table 10-11. Extension Code Bit Definitions
Slave Address
R/W Bit
Description
0000 000
0
General call address
0000 000
1
Start byte
0000 001
X
CBUS address
0000 010
X
Address that is reserved for different bus format
1111 0xx
X
10-bit slave address specification
10.4.10 Arbitration
When several master devices simultaneously output a start condition (when STTn is set to 1 before STDn is set to
1
Note
), communication among the master devices is performed as the number of clocks is adjusted until the data
differs. This kind of operation is called arbitration (n = 0, 1).
When one of the master devices loses in arbitration, an arbitration loss flag (ALDn) in IIC status register n (IICSn)
is set via the timing by which the arbitration loss occurred, and the SCLn and SDAn lines are both set for high
impedance, which releases the bus (n = 0, 1).
The arbitration loss is detected based on the timing of the next interrupt request (the eighth or ninth clock, when a
stop condition is detected, etc.) and the ALDn = 1 setting that has been made by software (n = 0, 1).
For details of interrupt request timing, see
10.4.5 I
2
C interrupt requests (INTIICn)
.
Note
STDn: Bit 1 of IIC status register n (IICSn)
STTn: Bit 1 of IIC control register n (IICCn)