USB CDC for reading and writing to host computer

[thealienthing]

I apologize if my question is too broad or if I'm simply asking the wrong question: but how do I use the USBHandle to write and read serial messages between the host and Daisy seed? I can see the ability to write to the USBHandle and handle it with a callback and my host PC can receive these messages too, but how can I create a true two way connection over the USB line? I'd like to write a serial interface application to be able to control my Daisy without the hardware peripheral and even facilitate unit testing.

The best I've been able to do is hack the Receive callback to write some kind of arbitrary response and then check in buffer on the next callback and ignore it if the input buffer matches what I just wrote, thus avoiding a feedback loop. But there's got to be a better way! Maybe there is a different class I'm overlooking but it feels reasonable that I should be able to have an arbitrary conversation over usb between my computer and Daisy! I appreciate any help and advice. Also, I'm trying to avoid adding a usb serial device to a Usart input as im trying to not add any more hardware and also have fewer usb jacks.

[takumi-ogata]

Hey thealienthing,

I'm really sorry for the delay in response.

What you're trying to do is possible.
We do it on the seed tester program all the time. We can type "RAM" from the PC, and it'll run a ram test and send back the results. So a 2-way communication totally works.

Unfortunately, we don't have any docs for serial in that direction nor a two-way example demonstrating what you're trying to do at the moment.
When we get a chance, we can either put together a quick example to share or at least paste relevant snippets from our tester firmware for you to see.

We would greatly appreciate your patience.