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The ground of both devices should also be made common. UART uses two data lines for sending (Tx) and receiving (Rx) data.

As it is asynchronous it doesn't need to send clock signal along with the data signals. There are also two different modes namely the 8-bit and 9-bit mode, in this tutorial we will configure the USART module to work in Asynchronous mode with 8-bit communication system, since it is the most used type of communication. If it overflows for four time it create a timing tick of about 1ms.Ĭ program lists about is written for this programming example.ĭiagram lists below is its full schematic.The USART can be configured in the following modes: It's unique for all interrupt source in Mid-Range PIC16F887 microcontroller. The void interrupt() is MikroC compiler's reserve keyword used for ISR. Timer0 interrupt flag must be tested first and clear before remaining code. To handle interrupt, targeting interrupt source must be written in interrupt service routine (ISR). Main program loop stay idle as there's no additional code to handle. It's interrupt flag and Timer0 register must be cleared first. Global interrupt, Timer0 interrupt must be enabled. Timer0 module is selected to operate in timer mode with 1:2 prescaler. Oscillator is driven from PIC16F887 internal RC oscillator using its maximum 8MHz frequency. It must be configure to output direction in its corresponding TRISD register. In main program setting up, RD0 of Port D is output pin. Simulation sample of this programming example However we use this advantage to create a simple 1ms timing delay seeing its effect. Timer interrupt is useful for creating a timer tick that schedule tasks in microcontroller program. It's automatically called whenever its interrupt flag is set, then it's executed and automatically return to previous program context. Timer0 interrupt is a thread written in ISR that doesn't need to be polled in main program loop. It must be enabled and handled in ISR to get full advantage. Timer0 module is able to trigger interrupt even it's operate in timer or counter mode.