PT2259
BYTE FORMAT
Every byte transmitted to the DATA line consists of 8 bits and each byte must be followed by an “acknowledge” bit. The
MSB is transmitted first.
ACKNOWLEDGE SIGNAL
During the ninth clock pulse, the microprocessor puts a resistive “high” level on the DATA line. If the peripheral audio
processor (PT2259) acknowledges, it will pull the DATA line from a “high” state to a “low” state during this acknowledge
clock phase so that the DATA line is in a stable “low” state during this clock pulse. Please refer to the diagram below.
The audio processor that has been address (PT2259) must generate an “acknowledge” signal after receiving each byte
or the DATA line will remain at the “high” level during the ninth clock pulse.
TRANSMISSION WITHOUT ACKNOWLEDGE
If you do not wish the audio processor (PT2259) to detect the “acknowledge” signal, a simpler microprocessor
transmission method can be used: after PT2259 has received a byte wait for one clock pulse and do not acknowledge it.
If this approach is used, however, there is a greater chance for faulty operations to occur and noise immunity will be
decreased.
I2C START TIME
When PT2259 is powered on, a short period must elapse before voltage becomes stable. After the power is turned on,
PT2259 must wait at least 200ms before it is able to send an I2C control signal otherwise control efficacy and normal
operation will be comprised. Please refer to the diagram below:
V1.3
5
July, 2009
PTC [ PRINCETON TECHNOLOGY CORP ]
