Toggle an LED using Timer1 with PIC16F15244

The 'pic16f15244-led-timer-example' code example uses the PIC16F15244 Curiosity Nano Development board to demonstrate how to toggle LED0 every second using Timer1 to configure that one second period.

PIC16F15244 Curiosity Nano Development Board:

Related Documentation

• PIC16F15244 Product Page

Software Used

• MPLAB® X IDE 6.10 or newer (microchip.com/mplab/mplab-x-ide)
• MPLAB® XC8 2.41 or a newer compiler (microchip.com/mplab/compilers)
• MPLAB® Code Configurator (MCC) 5.3.7 or newer (microchip.com/mplab/mplab-code-configurator)
• Microchip PIC16F1xxxx Series Device Support (1.18.352) or newer (packs.download.microchip.com/)

Hardware Used

• PIC16F15244 Curiosity Nano (EV09Z19A)
• Micro-USB to USB 2.0 cable

Setup

1. Connect the PIC16f15244 Curiosity Nano board to a PC using the Micro-USB to USB 2.0 cable.
2. Download and install MPLAB®X IDE version 6.10, or newer.
3. Download and install the XC8 C-Compiler version 2.41, or newer.
4. Open the 'pic16f15244-led-timer-example.X' project, as shown in Figure 1.

Figure 1: Open Project Window

5. Press Open Project to open the Project Properties window. Select the Curiosity tool from the tools drop-down menu, as shown in Figure 2.

Figure 2: Select the Nano in Project Properties Window

6. Press Make and Program Device to program the PIC, as shown in Figure 3. Verify if the device was successfully programmed, as shown in Figure 4.

Figure 3: 'Make and Program Device' Button

Figure 4: Program Complete

Operation

After the Curiosity Nano is programmed, LED0 states will switch from 'ON' to 'OFF' every second.

Timer1 is configured such that it will roll-over every second, causing an interrupt event to occur. Timer1 can be quickly configured using MCC. Figure 5 shows the configuration used to generate an interrupt once every second. During the Timer1 Interrupt Service Routine (ISR), pin RA2 is toggled, which allows LED0 to change states.

Figure 5: TMR1 Configuration in MCC

Example 1: TMR1 Interrupt Service Routine Code Snippet

static void Timer1_DefaultOverflowCallback(void)
{
    if(LED0_TRIS == 1)
    {
        LED0_SetDigitalOutput();
    }
    else
    {
        LED0_SetDigitalInput();
    }
}

Summary

The 'pic16f15244-led-timer-example' code example uses the PIC16F15244 Curiosity Nano Development board to demonstrate how to toggle LED0 every second using Timer1 to configure that one second period.