diff --git a/clock.c b/clock.c
new file mode 100644
--- /dev/null
+++ b/clock.c
@@ -0,0 +1,26 @@
+
+void SystemClock_Config(void)
+{
+
+  RCC_OscInitTypeDef RCC_OscInitStruct;
+  RCC_ClkInitTypeDef RCC_ClkInitStruct;
+  RCC_PeriphCLKInitTypeDef PeriphClkInit;
+
+  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48;
+  RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
+  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
+  HAL_RCC_OscConfig(&RCC_OscInitStruct);
+
+  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
+  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI48;
+  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
+  HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1);
+
+  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
+  PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_HSI48;
+  HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit);
+
+  __SYSCFG_CLK_ENABLE();
+
+}