As part of a project I am using Simulink to send and receive serial data. The shown setup only concerns the necessary parts for this question. I send the (string) output of a ramp signal with slope 1 every 5 seconds to COM9. This data is instantly forwarded to COM10. I am using the Virtual Serial Port Driver by Electronic Team to emulate the serial ports and forward the received data. Simulink then reads out the data at COM10 with a sample time = 0.05. I use Simulation Pacing in Simulink to ensure simulation time corresponds to wall clock time. I have attached my Simulink script.
The problem:
There are two scenarios.
1) The first one uses the setup as described above and as shown below.
Some time after T = 5 s, I expect Serial Port [10] to read "5". Instead, it reads "0", and will continue to lag behind 5 seconds, i.e., at T = 10 s, it will read "5", etc.
2) In the second setup, I do not read COM10 in Simulink, but use PuTTY to open a terminal at baud = 115200.
What happens is that right after pressing Run, COM10 receives a "0", and it will correctly receive "5" at T = 5 s, "10" at T = 10 s, etc. This is the desired behaviour for the simulation in scenario 1.
Question:
How can I get rid of the "delay" in scenario 1?
