Recover SerDes clock time values from custom DFECDR and CDR
SerDes Toolbox / Utilities
The IBIS-AMI clock_times block recovers the clock time values of a SerDes system when you use a custom DFECDR or CDR block instead of the ones provided with the SerDes Toolbox™. The block recovers the clock time values from the AMI_GetWave function and outputs them to the generated IBIS-AMI models.
The output of the IBIS-AMI clock_times block is two global variables,
extern double* Rx_clock_times_buf and
Rx_clock_times_idx. The block only creates the variables. You must add them to
your custom code to make them work. Together, the variables implement the
clock_times vector as defined in the IBIS 7.0 specifications.
clockValid— Update input at clockTime port
Update the input at clockTime port, specified as a scalar or vector. The value at the clockValid port results in only one clock times output per sample.
Each rising edge of the input signal at the clockValid port updates the S function that passes through the clockTime port. Usually this happens once per unit interval (UI).
clockTime— Clock time data
Clock time data, specified as an array. Clock time data is passed to the AMI wrapper code using an S function.
The time value at the clockTime port must be half UI before the actual data sample times.
Enable IBIS-AMI Offset— Offset clock time values by half UI
Offset clock time values by half UI, according to IBIS-AMI specifications.
The EDA tool allocates the clock times vector. The vector is referenced at the first
call by the AMI_GetWave function. The clock times are exactly half the bit time before the
input data signal is sampled. The algorithmic model returns nonnegative clock time values.
After the last valid clock tick in the clock times vector, a
the end of the vector. The clock ticks represented by clock times vector is strictly
To sample the output waveform, each valid value of the clock times vector is added to half the bit time (half the sample time for PAM4).
 IBIS 7.0 Specification, https://ibis.org/ver7.0/ver7_0.pdf.