PCA9665_2 © NXP B.V. 2006. All rights reserved.
Product data sheet Rev. 02 — 7 December 2006 25 of 91
NXP Semiconductors PCA9665
Fm+ parallel bus to I2C-bus controller

8.3.3 Slave Receiver Byte mode

In the Slave Receiver Byte mode, a number of data bytes are received from a master
transmitterone byte at a time (see Figure 9). To initiate the Slave Receiver mode,I2CADR
and I2CCON must be loaded as shown in Table29 and Table 30.
Theupper 7 bitsare the I2C-bus address to which PCA9665 will respond when addressed
by a master. GC is the control bit that allows the PCA9665 to respond or not to the
General Call address (00h).
When programmed to logic 1, the PCA9665 will acknowledge the General Call address.
When programmed to logic 0, the PCA9665 will not acknowledge the General Call
address.
ENSIO must be set to logic 1 to enable the I2C-bus interface. The AA bit must be set to
enable PCA9665 to acknowledge its own slave address, STA, STO, and SI must be reset.
WhenI2CADR and I2CCON have been initialized, the PCA9665 waits until it is addressed
byits own slave address followed by the data direction bit which must be ‘0’ (W) to operate
in the Slave Receiver mode. After its own slave address and the W bit have been
received, the Serial Interrupt flag (SI) is set, the Interrupt line (INT) goes LOW, and
I2CSTA is loaded with 60h. This status code is used to vector to an interrupt service
routine, and the appropriate action to be taken is detailed in Table31.
The Slave Receiver Buffered mode may also be entered when:
The arbitration is lost while the PCA9665 is in the master mode. See status 68h and
D8h.
The General Call Address (00h) has been received (General Call address enabled
with GC = 1). See status D0h.
If the AA bit is reset during a transfer,the PCA9665 will return a not acknowledge (logic 1)
on SDA after the next received data byte. While AA is reset, the I2C-bus state machine
does not respond to its own slave address. However, the I2C-bus is still monitored and
address recognition may be resumed at any time by setting AA. This means that the AA
bit may be used to temporarily isolate PCA9665 from the I2C-bus.
Table 29. I2CADR initialization
Bit 76543210
Symbol AD7 AD6 AD5 AD4 AD3 AD2 AD1 GC
Value own slave address X
Table 30. I2CCON initialization
Bit 76543210
Symbol AA ENSIO STA STO SI - - MODE
Value 11000XX0