Send serial data to Wi-Em from outsite network

Hi all,

I have done one small project with the Wi-Em. In this project, a PC was connected to a Linksys router together with the Wi-Em, that was mounted on a robot. Three of them (PC, Linksys router and the Wi-Em) make up a LAN. The PC would send instructions locally through the router to Wi-Em to direct the robot.

Could I ask is it possible for me to send instructions to the Wi-Em from a PC belongs an outside network (anywhere) and control the robot?

Thank in advance!


How are you communicating between the PC and the Wi-EM? Are you just using HTTP or TCP with some protocol that you have designed?

If so, yes you will be able to send instructions to the robot anywhere in the world, but it will not be as easy as doing it locally.

You should be able to configure your router to forward incoming connections for its IP address to the internal IP address of your Wi-Em. Now, you can provide the IP address of your router to any PC in the world and you should be able to communicate with the robot.

Some challenges of course…if you use DHCP for the Wi-EM, its IP address may change and your router will not forward correctly. If your router uses DHCP to get its IP address from your ISP, it could change, and you will have to update the remote clients. Opening up and forwarding the port to your local network has the potential for security issues and such.

Digi has announced they are offering support for iDigi in embedded products. iDigi is a service that makes it easier for you to manage and interact with your devices across the Internet. I’m not sure if iDigi support is released for the Wi-EM, but if it is, it would be an interesting option for you to investigate.

With iDigi, your Wi-EM would make a persistent connection to the iDigi servers. It would do this regardless of which network it is connected to, as long as it has internet access and can make an outbound connection. You would the modify your robot controller to make some calls into iDigi, using web services, and iDigi would then send the command down to the Wi-EM and to your robot. This would then continue to work as your Wi-EM moves from network to network, even if the IP address of it or the router changes.


Thank for your fast reply cpopp.

Yes, I am using TCP with a customed protocol.

As you suggestion, I have read the information in but it only gave some basic idea. I still don’t figure out exactly what to do to get my WiEm receive signal from outside network.

But I thought the configuration and usage should be the same as working with IP camera. I have followed the instructions in a tutorial video about that but I stuck at the last segment. After all configuration, what should I do to get to my WiEm (here is the IP camera).