JRC NJU26209 Manual page 7

2
I C Bus
When the NJU26209 is configured for I
data on the SDA pin and clocks data on the SCL pin. The SDA is an open drain pin requiring a pull-up resistance.
Pins AD1 and AD2 are used to configure the seven-bit SLAVE address of the serial host interface. (Table 6)
2
Table 6 I C Bus Interface Slave address
bit7
0
0
0
0
Start
* SLAVE address is 0 when AD1/2 is "Low". SLAVE address is 1 when AD1/2 is "High".
* SLAVE address is 0 when R/W is "W". SLAVE address is 1 when R/W is "R".
Note:
Both " Standard-Mode (100kbps)" and "Fast-Mode (400kbps)" data transfer rate are supported.
4-Wire Serial Interface
The serial host interface can be configured for 4-Wire Serial bus communication by setting SEL1="High" during the
Reset Sequence initialization. SHI bus communication is full-duplex; a write byte is shifted into the SDIN pin at the
same time that a read byte is shifted out of the SDOUT pin.
Data transfers are MSB first and are enabled by setting SSb = "Low". Data is clocked into SDIN on rising
transitions of SCK. Data is latched at SDOUT on falling transitions of SCK except for the first byte(MSB) which is
latched on the falling transitions of SSb. SDOUT is always CMOS output. SDOUT does not require a pull-up
resistance.
SSb
SCK
SDIN
SDOUT
unstable
Note : When the data-clock is less than 8 clocks, the input data is shifted to LSB side and is sent to the DSP core at the
transition of SSb="High".
When the data-clock is more than 8 clocks, the last 8 bit data becomes valid.
After sending LSB data, SDOUT transmits the MSB data which is received via SDIN until SSb becomes "High".
Ver.2008-12-04
2
C bus communication in SEL="Low", the serial host interface transfers
bit6 bit5
0 1
0 1
0 1
0 1
Slave Address ( 7bit )
bit
bit7
bit6
MSB
bit7 bit6
Fig. 4 4-Wire Serial Interface Timing
bit4 bit3
1 1
1 1
1 1
1 1
bit1
bit5
bit5 bit1
NJU26209
AD2 AD1
bit2 bit1
0 0
0 1
1 0
1 1
R/W
ACK
bit
bit0
LSB
bit0
unstable
R/W
bit0
R/W
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