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When acting as a slave transmitter or slave receiver, while PIN=0, the chip will suspend
ACCESS.bus transmission by holding the SCL line low until the PIN bit is set to logic 1 (inactive).
This prevents further data from being transmitted or received until the current data byte in S0 has
been read (when acting as slave receiver) or the next data byte is written to S0 (when acting as slave
transmitter).
PIN bit summary:
The PIN bit can be used in polled applications to test when a serial transmission has been
completed. When the ENI bit is also set, the PIN flag sets the internal interrupt via the nINT output.
In transmitter mode, after successful transmission of one byte on the ACCESS.bus the PIN bit will
be automatically reset to logic 0 (active) indicating a complete byte transmission.
In transmitter mode, PIN is set to logic 1 (inactive) each time register S0 is written.
In receiver mode, PIN is set to logic 0 (inactive) on completion of each received byte.
Subsequently, the SCL line will be held low until PIN is set to logic 1.
In receiver mode, when register S0 is read, PIN is set to logic 1 (inactive).
In slave receiver mode, an ACCESS.bus STOP condition will set PIN=0 (active).
PIN=0 if a bus error (BER) occurs.
Bit 6: Reserved , Logic 0.
Bit 5: STS. When in slave receiver mode, this flag is asserted when an externally generated STOP
condition is detected (used only in slave receiver mode).
Bit 4: BER. Bus error; a misplaced START or STOP condition has been detected. Resets nBB (to
logic 1; inactive), sets PIN=0 (active).
Bit 3: LRB/AD0 . Last Received Bit or Address 0 (general call) bit. This status bit serves a dual
function, and is valid only while PIN=0:
1. LRB holds the value of the last received bit over the ACCESS.bus while AAS=0 (not
addressed as slave).
Normally this will be the value of the slave acknowledgment; thus
checking for slave acknowledgment is done via testing of the LRB.
2. ADO; when AAS=1 (Addressed as slave condition) the ACCESS.bus controller has been
addressed as a slave. Under this condition, this bit becomes the AD0 bit and will be set to
logic 1 if the slave address received was the ‘general call’ (00h) address, or logic 0 if it was the
ACCESS.bus controller’s own slave address.
Bit 2: AAS. Addressed As Slave bit. Valid only when PIN=0. When acting as slave receiver, this
flag is set when an incoming address over the ACCESS.bus matches the value in own address
register S0’ (shifted by one bit) or if the ACCESS.bus ‘general call’ address (00h) has been
received (‘general call’ is indicated when AD0 status bit is also set to logic 1).
Bit 1: LAB. Lost Arbitration Bit. This bit is set when, in multi-master operation, arbitration is lost to
another master on the ACCESS.bus.