The C500 microcontroller family provides usually only one on-chip asynchronous serial communication channel (USART). If a second USART is required, an emulation of the missing interface may help to avoid an external hardware solution with additional electronic components.1 Introduction 32 General Operation and Hardware Environment 42.1 Supported Features 42.2 Required Resources 52.3 External Routing 62.4 Principles of Emulation 72.4.1 USART Write 72.4.2 USART READ 83 USART Emulation Software Des cription 93.1 Software Structure 93.2 Main Program 103.3 Emulation Subroutines 123.4 Baud Rate Calculation. 123.5 Load Measurement 153.6 Performance Limitations 163.7 Make File 173.8 Support of KitCON-513 Evaluation Board 18