From af8f6044f19796825645e29e197ee7a83f2a0398 Mon Sep 17 00:00:00 2001
From: Kymkim <oliver@kym-kim.com>
Date: Mon, 24 Mar 2025 13:55:43 -0700
Subject: [PATCH] test module stuff

---
 modules/testmodule/lib/main.c | 62 +++++++++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 modules/testmodule/lib/main.c

diff --git a/modules/testmodule/lib/main.c b/modules/testmodule/lib/main.c
new file mode 100644
index 00000000..45ece729
--- /dev/null
+++ b/modules/testmodule/lib/main.c
@@ -0,0 +1,62 @@
+#include "stm32f1xx_hal.h"
+
+#define NUM_COLS 2
+#define NUM_ROWS 2
+
+//Stores the GPIO and the PIN location - would be useful for the matrix
+typedef struct {
+    GPIO_TypeDef* GPIO;
+    uint16_t PIN;
+} keyMatrix ;
+
+keyMatrix matrix[NUM_COLS][NUM_ROWS] = {
+    {{GPIOA, GPIO_PIN_0},{GPIOA, GPIO_PIN_1}},  //Column
+    {{GPIOA, GPIO_PIN_2},{GPIOA, GPIO_PIN_3}}   //Row     
+};
+
+int main(void){
+
+    HAL_Init(); //Initialize the HAL Abstraction Layer
+
+    //Initialize a 2x2 pins
+    for(int col = 0; col<NUM_COLS; col++){
+        GPIO_InitTypeDef GPIO_InitCols = {0};
+        GPIO_InitCols.Pin = matrix[0][col].PIN;
+        GPIO_InitCols.Mode = GPIO_MODE_OUTPUT_PP;
+        GPIO_InitCols.Pull = GPIO_NOPULL;
+        GPIO_InitCols.Speed = GPIO_SPEED_FREQ_LOW;
+        HAL_GPIO_Init(matrix[0][col].GPIO, &GPIO_InitCols);
+    }
+
+    for(int row = 0; row<NUM_ROWS; row++){
+        GPIO_InitTypeDef GPIO_InitRows = {0};
+        GPIO_InitRows.Pin = matrix[1][row].PIN;
+        GPIO_InitRows.Mode = GPIO_MODE_INPUT;
+        GPIO_InitRows.Pull = GPIO_PULLDOWN;
+        HAL_GPIO_Init(matrix[0][row].GPIO, &GPIO_InitRows);
+    }
+
+
+    // TODO: Deboucing Code - I suggest not to use HAL_Delay() beacause it is blocking 
+    // and might affect performance and introduce input delay. 
+    for(int col=0; col<NUM_COLS; col++){
+        //Set column to high
+        HAL_GPIO_WritePin(matrix[0][col].GPIO, matrix[0][col].PIN, GPIO_PIN_SET);
+        
+        //Read each row pin
+        for(int row=0; row<NUM_ROWS; row++){
+            if(HAL_GPIO_ReadPin(matrix[1][row].GPIO, matrix[0][col].PIN)){
+                //Register Key Press here
+            }
+        }
+
+        //Set column to back to low
+        HAL_GPIO_WritePin(matrix[0][col].GPIO, matrix[0][col].PIN, GPIO_PIN_RESET);
+    }
+
+}
+
+/*
+    Would be nice if someone can abstract all of keyboard checking and initialization
+    into a separate include file so we can reuse it with other modules
+*/
\ No newline at end of file