101 Serial is somehow different from Uno

I have several similar serial protocols built using the SerialCommand library. They work well with many different Unos and with a Mega.

I have today installed the code for one of the Unos onto a 101 and have a baffling problem: my desktop app cannot receive serial messages from this.

With the same code on a Uno it works fine.

With the serial monitor it works fine on the 101.

With a third party serial terminal it works fine on the 101.

The 101 receives commands fine (and acts on them, so I know they’re going through).

But I cannot detect any response, not even in a data available event, from my desktop app.

Is there something subtly different about the 101 serial transmission?

thank,
Richard

Hi crfrancis, could you paste here an example sketch which shows the issue and the actual library you are using? Thanks!

OK here is a reduced version of the sketch, where I’ve removed all functionality related to external devices and put in some dummy responses. Nevertheless you can interact with it, for example, the command :GF# (terminated with a newline) gives the firmware version, :GS# gets the status etc.

It all works fine with a terminal, it’s when I use the same commands in an application (written with Xojo) which I can use perfectly well with exactly the same code running on a Uno, that it does not work.

thanks,
Richard

Arduino_SerialCommand_Library.zip (12.4 KB)

window53_slimline.zip (5.43 KB)

By the way, I forgot to mention that I'm using the USB serial port, not the TX/RX pins.

cheers, Richard

OK, I've found a (the?) solution: I declared data terminal ready to be true (in my desktop app) and that unblocked the receipt of messages.

This was not necessary with the Uno.

cheers, Richard

crfrancis: OK, I've found a (the?) solution: I declared data terminal ready to be true (in my desktop app) and that unblocked the receipt of messages.

Hi Richard,

Can you elaborate how you declared the data terminal ready and unblocked messages?

I'm running into an issue with serial coms that work fine with the a MEGA but not with the 101.