# pic18f47k42-scrolling-text-fire-mplab-mcc

**Repository Path**: bellstudio/pic18f47k42-scrolling-text-fire-mplab-mcc

## Basic Information

- **Project Name**: pic18f47k42-scrolling-text-fire-mplab-mcc
- **Description**: 用 PIC18F47K42 驱动一个 8x32 WS2812B RGB LED 阵列
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-09-14
- **Last Updated**: 2025-09-14

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

[![MCHP](./images/microchip.png)](https://www.microchip.com)

# WS2812B Scrolling Text, with Simulated Fire  
This project uses an PIC18F47K42 with a HPC Development board to drive an array of 8x32 WS2812B RGB LEDs to generate a variety of visual patterns, including a spinner, fire, shimmer, and scrolling text.
This project highlights the advanced array of Core Independent Peripherals (CIP) available on Microchip 8-bit PIC® microcontrollers, including the ADCC (Analog to Digital Converter with Computation), CLC (Configurable Custom Logic),
PWM (Pulse Width Modulation), SPI (Serial Peripheral Interface), and Timers. Furthermore, this project shows how custom timing protocols, such as WS2812B, can be implemented in peripherals, making it possible to use an 8-bit MCU for this task.

## Related Documentation

 [WS2812B Datasheet](http://www.world-semi.com/Certifications/WS2812B.html)  

Related projects:  
[RGB lighting with WS2812 using SPI and CCL](https://mplab-discover.microchip.com/v1/item/com.microchip.ide.project/com.microchip.subcategories.modules-and-peripherals.system-modules.Others/com.microchip.mcu8.mplabx.project.avr128da48-cnano-ws2812-mplab-mcc/1.0.1?view=about&s0=ws2812)  
[Using the Configurable Logic Cell (CLC) to Interface a PIC16F1509 and WS2811 LED Driver](https://ww1.microchip.com/downloads/en/AppNotes/00001606A.pdf)

## Software Used

- MPLAB® X IDE 5.50 or newer [(microchip.com/mplab/mplab-x-ide)](http://www.microchip.com/mplab/mplab-x-ide)
- MPLAB XC8 2.36 or a newer compiler [(microchip.com/mplab/compilers)](http://www.microchip.com/mplab/compilers)
- MPLAB Code Configurator (MCC) 5.0.3 or newer [(microchip.com/mplab/mplab-code-configurator)](https://www.microchip.com/mplab/mplab-code-configurator)
- MPLAB Code Configurator (MCC) Device Libraries PIC10 / PIC12 / PIC16 / PIC18 MCUs [(microchip.com/mplab/mplab-code-configurator)](https://www.microchip.com/mplab/mplab-code-configurator)
- Microchip PIC18F-K Series Device Support (1.6.125) or newer [(packs.download.microchip.com/)](https://packs.download.microchip.com/)


## Hardware Used

- [PIC18F47K42 PDIP](https://www.microchip.com/en-us/product/PIC18F47K42)
- Curiosity HPC Development Board [(DM164136)](https://www.microchip.com/en-us/development-tool/dm164136)

A custom PCB was made to use the MikroBUS™ socket on the Curiosity HPC Development Board. The Altium files produced are part of this repository.

## Setup

**Important: Perform these steps with the power OFF.**

1. Insert a PIC18F47K42 into the DIP socket on the Curiosity HPC Development Board.
2. Plug in the custom PCB into the MikroBUS socket on the Curiosity HPC Development Board.
3. Connect auxiliary power and the LED array to the PCB.

*Image of the Assembled System*
![Curiosity Nano Project Setup](./images/project_setup.jpg)  

### I/O Assignment

|	Signal						  |	Microcontroller Pin |
|---------------------------------|---------------------|
|  Analog Hue					  |	RA1					|
|  Analog Brightness   			  |	RA0					|
|  CLC1 Output	  				  |	RC6					|
|  Switch 1 (s1)				  |	RB4					|
|  LED1		  					  |	RA4					|
|  LED2			  				  |	RA5					|
|  LED3		  					  |	RA6					|
|  LED4				  			  |	RA7					|
|  SPI SCK1				  		  |	RC3					|
|  SPI SDI1			  			  |	RC4					|
|  SPI SDO1				  		  |	RC2					|  

![MCC Pin Manager Window View](./images/pin_manager.png)  

## Operation  
WS2812B is a custom serial protocol. To send a '1' or '0', the user must send a HIGH pulse and then a LOW pulse of a specific length. Sending a RET code requires a LOW pulse as shown below. The images below are from the WS2812B datasheet.  
![WS2812B Sequence Chart](./images/WS2812_sequence_chart.png)  
![WS2812B Data Transfer Time](./images/WS2812_data_transfer_time.png)  
![WS2812B Cascade Method](./images/WS2812_cascade.png)  

To implement WS2812B, PWM, SPI, and CCL peripherals were used to generate the specific waveforms.

### ADCC Module Configuration  
The ADCC configuration in this example was used to measure the analog voltage from 2 potentiometers: one for hue and the other for brightness of the WS2812B array.  

The peripheral was configured to take single measurements for each of the two channels used, with VDD as the positive reference, VSS as the negative reference, and using left result alignment.  

The selected clock source was FOSC/ADCLK and the clock used was FOSC/64. This set the time to complete 1 bit conversion (TAD) as 1µs, a sampling frequency of 86.96 kHz and a conversion time of 11.5µs.
See image below for ADCC setup.  
![ADCC Configuration](./images/ADCC_config.png)


### TMR1 Timer Configuration  
TMR1 was set up with a period of 20 ms. This was achieved by using the clock source of FOSC/4, with a prescaler of 1:8, and TMR1 was synchronized to the system clock.  

This timer is used in the main.c file to update the display functions.
See image below for TMR1 setup.  
![TMR1 Configuration](./images/TMR1_config.png)  

### TMR2 Timer Configuration  
TMR2 was set up with a period of 630 ns. This was achieved by using the clock source of FOSC/4, with a prescaler of 1:1, and a set period of 630 ns. With clock resolution, this is an actual period of 625 ns.
See image below for TMR2 setup.  
![TMR2 Configuration](./images/TMR2_config.png)

### PWM5 Configuration  
PWM5 uses TMR2 as its base timer and set with a duty cycle of 25%. This gives a HIGH time of 156.25 ns and a LOW time of 468.75 ns.
See image below for PWM5 setup.  
![PWM5 Configuration](./images/PWM5_config.png)

### PWM6 Configuration  
PWM6 used TMR2 as its base timer and set with a duty cycle of 66%. This gives a HIGH time of 412.5 ns and a LOW time of 212.5 ns.
See image below for PWM6 setup.  
![PWM6 Configuration](./images/PWM6_config.png)

### SPI1 Configuration   
SPI1 was set up in SPI Host mode, with input data sampled at the middle. Clock polarity was Idle Low and Active High. Clock edge was idle to active. The SPI clock source was TMR2_Postscaled, resulting in a SPI clock of 800 kHz. See image below for SPI1 setup.  
![SPI1 Configuration](./images/SPI1_config.png)

### CLC1 Config  
CLC1 was used to put together the following signals to create the custom protocol required for the WS2812B: SPI1 SCK, SPI1 SDO, PWM5 and PWM6.
The mode selected was AND-OR. See image below for CLC1 setup.  
![CLC1 Configuration](./images/CLC1_config.png)

## Summary  
This example shows how to drive a WS2812B 8x32 RGB LED array using the PIC18F47K42.