User`s guide

From Wave Device
5-219
the signal sample rate was 8 kHz, this small buffer could hold approximately
0.005 second of data.)
If the simulation throughput rate is higher than the hardware throughput
rate, the buffer remains empty throughout the simulation. If necessary, the
From Wave Device block simply waits for new samples to become available on
the buffer (the block does not interpolate between samples). More typically, the
simulation throughput rate is lower than the hardware throughput rate, and
the buffer tends to fill over the duration of the simulation.
Troubleshooting
If the buffer size is too small in relation to the simulation throughput rate, the
buffer may fill before the entire length of signal is processed. This usually
results in a device error or undesired device output. When this problem occurs,
you can choose to either increase the buffer size or the simulation throughput
rate:
•Increase the buffer size
The
Queue duration parameter specifies the duration of signal, T
b
(in
real-time seconds), that can be buffered in hardware during the simulation.
Equivalently, this is the maximum length of time that the block’s data
acquisition can lag the hardware’s data acquisition. The number of frames
buffered is approximately
where F
s
is the sample rate of the signal and M is the number of samples per
frame. The required buffer size for a given signal depends on the signal
board
Hardware buffer with
5-frame capacity
Simulink execution rate varies.Hardware execution rate is
No delays Simulation delay
T
b
F
s
M
-------------