1.1 Organization Of Data Sheet...................................................................................1-11.2 Introduction...............................................................................................................1-11.3 Features....................................................................................................................1-3SECTION 2HARDWARE DEs criptION2.1 Power Supply Configurations................................................................................2-12.2 Clock Generation Circuitry.....................................................................................2-12.3 MC145540 ADPCM Codec....................................................................................2-42.4 MC68HC705C8P.....................................................................................................2-52.5 MC145407 and EIA232 Port Des cription.............................................................2-62.6 Computer Terminal Interface Des criptions..........................................................2-72.7 Jumper Des criptions ...............................................................................................2-82.8 Handset....................................................................................................................2-10SECTION 3OPERATING CONFIGURATIONS3.1 MC145537EVK Single Board Analog End-to-End Operation...........................3-13.2 MC145537EVK to MC145537EVK Full-Duplex Analog End-to-End...............3-23.3 MC145537EVK to MC145536EVK Full-Duplex Analog End-to-End...............3-7SECTION 4MICROCONTROLLER SOFTWARE COMMAND SET4.1 Computer Terminal Software Command Set......................................................4-1Figure 1-1.MC145537EVK Functional Block Diagram ................................................1-2Figure 2-1. DSW1 Settings for Transcoding Rates.......................................................2-2Figure 2-2. Jumper Positions for Switching Transmit and Receive Circuits of theEIA-232 Serial Computer Terminal Interface.............................................2-6Figure 3-1. Jumper Settings for Digital Loopback Analog End-to-End Operation....3-2Figure 3-2. Recommended Configuration for MC145537EVK to MC145537EVKOperation.........................................................................................................3-4Figure 3-3. Recommended Configuration for MC145537EVK to MC145536EVKOperation.........................................................................................................3-8Figure 4-1. Input / Output Modes of the MC145540 ADPCM Codec.........................4-3