diff --git a/firmware/docs/rusefi_custom_chibios.txt b/firmware/docs/rusefi_custom_chibios.txt
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+rusEfi is trying to use latest stable ChibiOS with minimal changes
+
+At the moment rusEfi custom version of ChibiOS has the following changes:
+
+1) LSE auto-detection, see rusefi_lse_fix.h see LSE_TIMEOUT
+
+2) ?
+
+3) ?
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