31.2.4.1.5 Acknowledge Sequence Timing
An Acknowledge sequence (see Figure 31-27) is
         enabled by setting the Acknowledge Sequence Enable (ACKEN)
         bit. When this bit is set, the SCL pin is pulled low and the contents of the Acknowledge
         Data (ACKDT) bit are presented on the SDA pin. If the user wishes to generate an
         Acknowledge, then the ACKDT bit must be cleared. If not, the user must set the ACKDT bit
         before starting an Acknowledge sequence. The Baud Rate Generator then counts for one
         rollover period (TBRG) and the SCL pin is deasserted (pulled high). When the SCL
         pin is sampled high (clock arbitration), the Baud Rate Generator counts for
         TBRG. The SCL pin is then pulled low. Following this, the ACKEN bit is
         automatically cleared, the Baud Rate Generator is turned off and the MSSP module then goes
         into Idle mode.
      