THE I2C-BUS SPECIFICATION, VERSION 2.1, JANUARY 2000
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10.1.1 GENERAL CALL ADDRESS
The general call address is for addressing every device connected to the I2C-bus. However, if a device doesn’t
need any of the data supplied within the general call structure, it can ignore this address by not issuing an
acknowledgment. If a device does require data from a general call address, it will acknowledge this address and
behave as a slave-receiver. The second and following bytes will be acknowledged by every slave-receiver
capable of handling this data. A slave which cannot process one of these bytes must ignore it by
not-acknowledging. The meaning of the general call address is always specified in the second byte (see Fig.15).
There are two cases to consider:
· When the least significant bit B is a ‘zero’.
· When the least significant bit B is a ‘one’.
the second byte.