I have an ICOM IC-7300 connected via USB to a Raspberry Pi set up for server operation. Accessing this server via the Internet is a Win 10 laptop running WFVIEW. This all works well. In the Win 10 laptop I have two virtual audio cables and a TCP link connected to WSJT-X. This all works well with WSJT-X able to control the TX frequencies. No problem so far.
Now the problem.
I decided to try MMSSTV, a popular SSTV program. Again, it is connected to the two virtual audio cables and that connection works fine. Rig control is the issue. I installed a VSPE virtual com port, and used it to connect to the MMSSTV com port.
The rig commands, although correct, are not received by WFVIEW and do not create a Pseudo Terminal.
Now I am going to make a long story short. To troubleshoot the problem I made the simplest test setup that I could.
I connected Tera Term, a common terminal emulator, to the same come port as MMSSTV was using and proceeded to test.
Using a file with a transmit command from Tera Term, the command was received by WFVIEW and a pseudo terminal created with a log entry of the correct command. This worked. It worked regardless of Tera Term’s bit rate setting also. The only difference that I could detect between Tera Term and MMSSTV was that the characters from MMSSTV visually seemed to be sent at a much slower rate, a significant gap between characters.
To prove that this was the issue, I optioned Tera Term with a 1ms delay between characters, and sent the same file. With that small delay, it was not recognized by WFVIEW and no Pseudo Terminal appeared in the log. This was a repeatable situation;
remove the delay, and the command is sent and recognized by the 7300.
Normally, delays between characters within reason should be accepted. The monitoring capability of the VSPE virtual com port also showed correct data going to WFVIEW but still no WFVIEW log info.
It seems that the pseudo terminal buffer is not being created or sent when there are async character delays. Is there some control character such as CR or LF that would help? I could pre or append them after a delay if appropriate.
I realize this is a rather obscure problem that few people will encounter, but if I could make it work,I would like to.
I would appreciate any ideas or approaches on further troubleshooting of my situation.