Re: 9-pin male connector...are you thinking of an RS232 connector? The USB-TTL cables should have 3 exposed leads at the end (RX, TX, and GND) to connect directly to the Netduino's headers...
For RS232, you can use an RS232 shield. CuteDigi makes one, and there are other breakouts and options available. We can point you in the right direction.
My bad: I'd thought that I somehow needed to modify a USB-TTL cable to connect to the DB9 port on an RS232 shield.
Here's a description of what I'm seeing below:
I have the RS232 shield attached to my Netduino plus board. And, I have a Parallax USB-to-Serial cable that i'd used to connect my PC (Windows 7, 64-bit) to the Netduino board.
In the Properties/.NET Micro Framework tab, Iâ€™ve selected Serial as the Transport and Visual Studio has correctly identified COM1 as the only port available.
This port corresponds to the Parallax cable thatâ€™s attached to my machine. When I open Device Manager, a â€œUSB Serial Port (COM1)â€ appears. And, when I open Control Panel/Hardware and Sound/Devices and Printers, this device appears as an FT232R USB UART.
What I see when attempting to deploy is:
1) â€œPreparing to deploy assemblies to the device.â€ in Visual Studio (after I specified Build/Deploy).
2) A red LED begins flashing on the RS232 shield (mounted above the Netduino).
3) Finally, the LED stops flashing and an error appears in Visual Studio: â€œDeploy failed.â€
4) A further error appears in Visual Studioâ€™s â€œError Listâ€: â€œUnable to communicate with device = Serial:COM1â€
Any thoughts? (I am able to deploy this same code over USB; so, the issue appears to be with the serial deployment itself.)