updted content of write board specific software

Author: balotofi

how-tos/write_board_software.md

@@ -6,6 +6,84 @@ layout: default
 lang: en
 ---
 
+# Writing the Board-Specific Software File
+
+## Overview
+
+This guide explains how to write the board-specific software file for the subsystem board. This involves modifying key parameters and configurations to match the hardware setup.
+
+## Before you start
+
+Before writing the board-specific software file, ensure:
+
+* You have the necessary software development tools installed (e.g., MPLAB X, XC8 compiler).
+* You have access to the firmware repository.
+* You understand the board’s hardware specifications and required configurations.
+
+## Modifying the Board-Specific Software File
+
+1. **Locate the Board-Specific File**
+    
+    Navigate to the firmware repository and open the file corresponding to your board (e.g., `board_config.h`).
+
+2. **Update the Microcontroller Settings**
+    
+    Modify the following parameters to match your board’s specifications:
+
+    ```c
+    #define CPU_FREQUENCY 32000000  // Set the correct clock frequency
+    #define UART_BAUDRATE 9600       // Set the UART communication speed
+    ```
+
+3. **Configure the I/O Pins**
+    
+    Adjust the pin configurations based on your hardware connections:
+
+    ```c
+    #define LED_PIN TRISBbits.TRISB0  // Set LED pin as output
+    #define BUTTON_PIN TRISBbits.TRISB1  // Set Button pin as input
+    ```
+
+4. **Define Communication Protocols**
+    
+    If using SPI, I2C, or UART, configure the relevant registers:
+
+    ```c
+    void initUART() {
+        TXSTAbits.BRGH = 1;  // High-speed mode
+        BAUDCONbits.BRG16 = 1;
+        SPBRGH = 0x00;
+        SPBRG = 207;  // Baud rate setting
+    }
+    ```
+
+### Updating Other Files
+
+Some additional files may require changes to ensure proper integration:
+
+1. **Modify `main.c`**
+    
+    Ensure the initialization functions for peripherals and board-specific settings are included:
+    
+    ```c
+    void main() {
+        initUART();
+        while (1) {
+            // Main program loop
+        }
+    }
+    ```
+
+2. **Update `Makefile` or Build Configurations**
+    
+    If using a custom linker script or additional libraries, ensure they are properly linked in your project settings.
+
+## See also
+
+* [Microchip MPLAB X Documentation](https://www.microchip.com/mplabx)
+* [PIC18F67J94 Datasheet](https://www.microchip.com/wwwproducts/en/PIC18F67J94)
+* [Troubleshooting Common Compilation Errors](#troubleshooting)
+
 
 
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