Crystal Clock Error Routine at Startup in PSoC® 3, and PSoC 5LP - KBA85476

Version: **

 

Question: What happens if the external XTAL clock settings in the .cydwr settings and the actual external crystal oscillator frequency are considerably different?

 

Answer:

To counter this situation the CPU gets stuck in the Clock Startup procedure. The ClockSetup() phase is associated with a timeout window exceeding, which results in calling the CyClockStartupError().The CPU gets stuck in an infinite while loop within this routine. The routines can be found in cyfitter_cfg.c. Figures 1 and 2 depict the same.

Figure 1. Clock Setup Routine Executed During Startup

Figure 2. Clock Startup Error Routine; by Default This Would Run into an Infinite While Loop