Issues with Serial Communication of TMS320F28379D using SCI with Matlab Simulink

Hi there,

I coded the F28379D, to generate 20 ms sinewave using Matlab simulink as shown below.

Case 1:

Sine Sample time: 5e-3

Sine Samples Per Second: 4

Rate transition of trasmitter: 5e-3

sample time of receiver: 5e-3

->The result at receiver end of Matlab was as expected as shown below,

Case 2:

->To improve the resolution of the sine wave, the data is modified as,

Sine Sample time: 1e-3

Sine Samples Per Second: 20

Rate transition of trasmitter: 1e-3

sample time of receiver: 1e-3

->The received data is having the unexpected high values after 3 secs. Before 3 secs data was fine.

What is the reason for such behaviour?. Is a rate transition value of 5e-3, the lowest I can use for the transmitter for this board? How can I find the lowest supported rate transition for error free operation?.

The hardware settings are as shown below,

The SCI transmitter Header and Terminator are set to null i., ''.

Mathworks Version: 2020a

CCS Version:8.3.1

Thanks.