Adding left/key_scanner.[ch] which I totally forgot.

left/src/key_scanner.c

@@ -0,0 +1,21 @@
+#include "fsl_lptmr.h"
+#include "key_scanner.h"
+#include "main.h"
+
+void KEY_SCANNER_HANDLER(void)
+{
+    KeyMatrix_ScanRow(&keyMatrix);
+    LPTMR_ClearStatusFlags(KEY_SCANNER_LPTMR_BASEADDR, kLPTMR_TimerCompareFlag);
+}
+
+void InitKeyScanner(void)
+{
+    lptmr_config_t lptmrConfig;
+    LPTMR_GetDefaultConfig(&lptmrConfig);
+    LPTMR_Init(KEY_SCANNER_LPTMR_BASEADDR, &lptmrConfig);
+
+    LPTMR_SetTimerPeriod(KEY_SCANNER_LPTMR_BASEADDR, MSEC_TO_COUNT(KEY_SCANNER_INTERVAL_MSEC, LPTMR_SOURCE_CLOCK));
+    LPTMR_EnableInterrupts(KEY_SCANNER_LPTMR_BASEADDR, kLPTMR_TimerInterruptEnable);
+    EnableIRQ(KEY_SCANNER_LPTMR_IRQ_ID);
+    LPTMR_StartTimer(KEY_SCANNER_LPTMR_BASEADDR);
+}

left/src/key_scanner.h

@@ -0,0 +1,18 @@
+#ifndef __KEY_SCANNER_H__
+#define __KEY_SCANNER_H__
+
+// Macros:
+
+    #define LPTMR_SOURCE_CLOCK CLOCK_GetFreq(kCLOCK_LpoClk)
+
+    #define KEY_SCANNER_LPTMR_BASEADDR LPTMR0
+    #define KEY_SCANNER_LPTMR_IRQ_ID   LPTMR0_IRQn
+    #define KEY_SCANNER_HANDLER        LPTMR0_IRQHandler
+
+    #define KEY_SCANNER_INTERVAL_MSEC 1
+
+// Functions:
+
+    void InitKeyScanner(void);
+
+#endif