Running the demonstration
UM1590
Doc ID 023892 Rev 1
2.2.2 Clock
failure
At any demonstration level, if no clock is present on OSC_IN (broken or disconnected
crystal), the message shown in
is displayed on the LCD screen.
Figure 12.
No HSE clock detected
If the 8 MHz crystal is not reconnected in the next few seconds, the MCU enters Standby
mode. If the 8 MHz crystal is reconnected within a few seconds, a system reset is
generated.
Note:
The clock security system (CSS) feeds the MCU with the HSI OSC used as an emergency
clock if no clock is detected.
When a timeout occurs, the MCU enters Standby mode and the message shown in
is displayed on the LCD screen.
Figure 13.
Standby mode entered
1.
The demonstration does not restart as long as the 8 MHz crystal is not present.
2.
Connecting the 8 MHz crystal oscillator after reset may not restart the demonstration correctly. The crystal
oscillator must be connected before starting the demo.
