BAT32G1x9 user manual | Chapter 20 Serial interface IICA
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Rev.1.02
20.2.2
Slave address register n(SVAn).
This is the register that holds the 7-bit local station address {A6, A5, A4, A3, A2, A1, A0} when used as a slave.
The SVAn register is set by the 8-bit memory operation instruction. However, when the STDn bit is "1" (start
condition detected), it is forbidden to overwrite this register.
After generating a reset signal, the value of this register changes to "00H".
Figure 20-4 Format of the slave address register n (SVAn).
After reset: 00H,
R/W
Symbol
7 6 5 4 3 2 1 0
Swan
Note: bit0
is fixed to
"0".
20.2.3
SO latches
The SO latch holds the output level of the SDAAn pin.
20.2.4
Wake-up control circuitry
This circuit generates an interrupt request (INTIICAn) when the address value set to the slave address register
n(SVAn) is the same as the received address or when an extension code is received.
20.2.5
Serial clock counter
During the send or receive process, this counter counts the output or input serial clock to check whether 8 bits
of data have been sent and received.
20.2.6
Interrupt request signal generation circuit
This circuit control generates an interrupt request signal (INTIICAn). An I2C interrupt request is generated by the
following
two
triggers.
• Drop of the 8th or 9th serial clock (set by the WTIMn bit).
•
Interrupt request (set via SPIEn bit) due to detection of a stop condition.
Note: WTIMn
bit:
bit3
of
IICA
control register
n0
(IICCTLn0
).
SPIEn bit:
bit4
of
IICA
control register
n0
(IICCTLn0
).
20.2.7
Serial clock control circuitry
In master mode, this circuit generates the output from the sample clock to the clock of the SCLAn pin.
20.2.8
Serial clock wait control circuit
This circuit controls the wait timing.
20.2.9
Ack generation circuit, stop condition detection circuit, start condition detection circuit, Ack
detection circuit
These circuits generate and detect various states.
20.2.10
Data hold time correction circuit
This circuit generates a data hold time for the serial clock to drop.
20.2.11
Start conditional generation circuitry
If stTn is positioned "1", the circuit generates a start condition.
However, in a state where appointment communication is prohibited (IICRSVn bit =1) and the bus is not
released (IICBSYn bit=1), the start condition request is ignored and the STCFn position "1" is changed.
20.2.12
Stop condition generation circuitry
If the SPTn position is "1", the circuit generates a stop condition.
20.2.13
Bus status detection circuitry
This circuit detects whether the bus is released by detecting the start and stop conditions. However, the bus
state cannot be detected immediately at the very beginning of operation, so the initial state of the bus state
detection circuit must be set by the STCENn bit.
A6
A5
A4
A3
A2
A1
A0
0
Note