Appendix B - Time stamp limits

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Transitional timing and state with timestamp
When transitional timing or state with time stamp mode is used, The GoLogic uses a 32-bit value to store each sample’s elapsed time. The maximum elapsed time for a sample is...

2^32 = 4,294,967,296

Time per sample = 1 / sampling frequency

Minimum time stamp per sample = 1 x time per sample

Maximum time stamp per sample = 4,294,967,296 x time per sample

The following table lists the available sampling frequencies, time per sample, minimum time per sample, and maximum time per sample...

 
    Time   Minimum time   Maximum time
Sampling
Frequency
  per sample   per sample   per sample
                       
500 Hz   2   ms   2   ms   99.42   days
1 KHz   1   ms   1   ms   49.71   days
2 KHz   500   us   500   us   24.86   days
10 KHz   100   us   100   us   4.97   days
25 KHz   40   us   40   us   1.99   days
50 KHz   20   us   20   us   23.86   hours
100 KHz   10   us   10   us   11.93   hours
250 KHz   4   us   4   us   4.77   hours
500 KHz   2   us   2   us   2.39   hours
1 MHz   1   us   1   us   1.19   hours
2.5 MHz   400   ns   400   ns   28.63   min
5 MHz   200   ns   200   ns   14.32   min
12.5 MHz   80   ns   80   ns   5.73   min
25 MHz   40   ns   40   ns   2.86   min
50 MHz   20   ns   20   ns   1.43   min
125 MHz*   8   ns   8   ns   0.57   min
250 MHz  

Time stamp not available at this frequency

500 MHz   Time stamp not available at this frequency
                       
* Timer uses this sampling rate during state with timestamp mode.
I2C state analysis
When I2C State Analysis mode is used, the GoLogic uses a 26-bit value to store each sample’s elapsed time. The maximum elapsed time for a sample is...

2^26 = 67,108,864

Time per sample = 1 / sampling frequency

Minimum time stamp per sample = 1 x time per sample

Maximum time stamp per sample = 67,108,864 x time per sample

The following table lists the available sampling frequencies, time per sample, minimum time per sample, and maximum time per sample...

 
    Time   Minimum time   Maximum time
Sampling
Frequency
  per sample   per sample   per sample
                       
500 KHz   2   us   2   us   2.24   min
2.5 MHz   400   ns   400   ns   26.84   sec
12.5 MHz   80   ns   80   ns   5.37   sec
  • The 500 KHz sampling frequency is used for the 100 kilobits-per-second I2C bus. The GoLogic samples the I2C SDA and SCL signals every 2 microseconds. A time stamp rollover occurs if the I2C bus is inactive for more than 2.24 minutes.
  • The 2.5 MHz sampling frequency is used for the 400 kilobits-per-second I2C bus. The GoLogic samples the I2C SDA and SCL signals every 400 nanoseconds. A time stamp rollover occurs if the I2C bus is inactive for more than 26.84 seconds.
  • The 12.5 MHz sampling frequency is used for the 3.4 megabits-per-second I2C bus. The GoLogic samples the I2C SDA and SCL signals every 80 nanoseconds. A time stamp rollover occurs if the I2C bus is inactive for more than 5.37 seconds.
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