• Does this answer your question? How to receive serial data with c# on a raspberry with mono – Milliways 28 mins ago
• “In the picture you can see” no I can’t = post legible text not pictures – Milliways 22 mins ago
• Ah, let me see. So let me summarized what you have done so far. Let me know if I misunderstood something. (1) You have installed mono in Rpi, (2) You have written a C# program which can send the 20 character string/message “Sent from Raspberry!” and Linux/MsWin PC on the opposite side, receives the message correctly. So far so good. (Fig 1, 2 above) (3) Now you did send/receive in the opposite direction: (a) Win sends the message “Sent to Raspberry”, (b) but at this point there is something I don’t understand: How come Fig 3 right panel gets the message “… Send command not found …”.? – tlfong01 22 mins ago   
• It appear at this point Windows cannot found the “send command”. (4) If Window says there is no “send command” to sen out something, then of course at the Rpi side you get two empty panels. My quick and dirty conclusion is that Rpi’s C# program is verified good to sent out something, but no chance yet to verify that the same C# program can receive something, because the opposite side has not yet sent anything. In other words, Rpi is good. It is the other side evil Windows fault! – tlfong01 19 mins ago   
• One more thing. Please let me know what sort of “Windows” “computer” is on the other side, is it an evil WinTel PC running Win10, or a righteous AMD linux PC running uBantu? It now appears to me the problem is on the evil side, not being able to send out something. – tlfong01 7 secs ago   Edit   
• But on second thought, perhaps I jumped to the wrong conclusion too quickly: Windows did sent out the message “Send to Raspberry”, but on the Rpi side, it is not the C# program that get the message. It is the quick guy, namely bash, gets the message and replies to the evil Windows that there is such command as “Send” (the first word of the command string bash receives”. – tlfong01 just now   Edit

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