diff --git a/ex_4/main.c b/ex_4/main.c
index c1d93c22dad1892c30e0133a744f9d665ba4421f..dc71c30db3dd846e859b775b4003fca1a32d3fdf 100644
--- a/ex_4/main.c
+++ b/ex_4/main.c
@@ -169,4 +169,17 @@ int8_t sensor_config() {
 }
 
 int main(void) {
+
+  uint32_t err_code = spi_config();
+  if (err_code != NRF_SUCCESS)
+  {
+    // error check failed!
+  }
+
+  err_code = sensor_config();
+  if (err_code != NRF_SUCCESS)
+  {
+    // error check failed!
+  }
+
 }
diff --git a/ex_4/pca10040/blank/ses/ex4_Release.jlink b/ex_4/pca10040/blank/ses/ex4_Release.jlink
new file mode 100644
index 0000000000000000000000000000000000000000..292d9a0285da5394049932321a6ed1feb16950af
--- /dev/null
+++ b/ex_4/pca10040/blank/ses/ex4_Release.jlink
@@ -0,0 +1,39 @@
+[BREAKPOINTS]
+ForceImpTypeAny = 0
+ShowInfoWin = 1
+EnableFlashBP = 2
+BPDuringExecution = 0
+[CFI]
+CFISize = 0x00
+CFIAddr = 0x00
+[CPU]
+MonModeVTableAddr = 0xFFFFFFFF
+MonModeDebug = 0
+MaxNumAPs = 0
+LowPowerHandlingMode = 0
+OverrideMemMap = 0
+AllowSimulation = 1
+ScriptFile=""
+[FLASH]
+CacheExcludeSize = 0x00
+CacheExcludeAddr = 0x00
+MinNumBytesFlashDL = 0
+SkipProgOnCRCMatch = 1
+VerifyDownload = 1
+AllowCaching = 1
+EnableFlashDL = 2
+Override = 0
+Device="ARM7"
+[GENERAL]
+WorkRAMSize = 0x00
+WorkRAMAddr = 0x00
+RAMUsageLimit = 0x00
+[SWO]
+SWOLogFile=""
+[MEM]
+RdOverrideOrMask = 0x00
+RdOverrideAndMask = 0xFFFFFFFF
+RdOverrideAddr = 0xFFFFFFFF
+WrOverrideOrMask = 0x00
+WrOverrideAndMask = 0xFFFFFFFF
+WrOverrideAddr = 0xFFFFFFFF