use external 32.768 kHz oscillator for RTC

Change-Id: Ic4630abececdb631e8cc15baab7137fc15e2a66a
diff --git a/sysmoOCTSIM/atmel_start_config.atstart b/sysmoOCTSIM/atmel_start_config.atstart
index f3620ee..385c890 100644
--- a/sysmoOCTSIM/atmel_start_config.atstart
+++ b/sysmoOCTSIM/atmel_start_config.atstart
@@ -787,8 +787,8 @@
       enable_xosc32k: true
       osculp32k_calib: 0
       osculp32k_calib_enable: false
-      rtc_1khz_selection: true
-      rtc_source_oscillator: 32kHz Ultra Low Power Internal Oscillator (OSCULP32K)
+      rtc_1khz_selection: false
+      rtc_source_oscillator: 32kHz External Crystal Oscillator (XOSC32K)
       xosc32k_arch_cfden: false
       xosc32k_arch_cfdeo: false
       xosc32k_arch_cgm: Standard mode