Cisco Codec EQ Serial Interface Not Giving Response

[nathansmith159]

Hello all. I'm using the Cisco Codec EQ and trying to send it serial commands to once of the USB ports.

I'm using a Global Cache Global Connect which creates a TCP server and sends whatever bytes I send over port 4999 straight through to the DB-9 port. Then, the DB-9 to USB adapter, and for what I can tell that's good. My problem mostly is that because I'm not getting anything from the codec. From the perspective of the Global Cache, no matter what I send to it, it's nothing. I've enabled the port in the web settings, disabled LoginRequired (even if that were still on, however, I should be getting some bytes back from the codec). @kobrien86 mentioned here to disable Outbound Control, and the version of RoomOS that we're using (11.9 IIRC) doesn't support this feature.

I can SSH into it and give it commands, I can use the micro-USB port into my laptop and PuTTY into it after installing the driver as mentioned in the docs. I cannot, however, use PuTTY on the USB interface to connect to the codec, though it's unclear if that's something that should be able to work.

The Global Connect is really good for troubleshooting because it has a utility where you can manually send bytes over the DB-9 port and see what response you get. No matter what I send, I get nothing back. I'm wondering if there's a delimiter that I don't know about, because the format of a serial command isn't specified in the RoomOS docs. Is it ascii "\n", "0x0a", "0x0d", "0x0a0x0d"? I've tried every delimiter and combination that I could think of, and I still get nothing back. 

Any help or step in the right direction would be appreciated.

[PJMack]

Nathan - what USB port are you trying to use - the USB-C port? That is not a maintenance port, that's what the Micro USB port is for. Unless I'm misunderstanding your issue, I think you are just using the wrong port, you said the MicroUSB port works, That's what you should be using. 

From the datasheet:

From the install guide: 

[nathansmith159]

Thanks for the reply. 

I'm using the USB-A -> DB-9 cable to send the Codec serial commands. On the DB-9 is the Global Cache Global Connect box I was talking about.

I understand that the Micro-USB is for Maintenance and that's how you can send the Codec commands, but also the Codec should be able to be serially controlled on the USB-A ports as well. The docs never explicitly say this which is frustrating, but it makes sense because the Micro-USB port is locked at 115200 baud, but on the others you can change it. I assume this is for troubleshooting, but the point is that you can change the baud rate on the other ports. I would expect this means that I can send it xCommands over a serial connection using the USB-A ports.

I just haven't been able to find the right combination of settings and commands to get it to do anything.

[PJMack]

The manual does not suggest the codecs can be serially controlled through the USB-A ports, it's actually pretty clear on this topic. This screenshot is from page 442 of the latest admin guide. Hope this helps. 

[nathansmith159]

I followed those steps and I was able to PuTTY into it on my laptop, but only after installing the driver.

I guess I'll ask more generally: How do people get serial control of this device? Because unless the device is running Windows/MacOS, it can't install that driver. The only problem I have is one I'm sure has been solved on this device, because serial control of this thing is something other people have been able to achieve. I'm just having trouble and I don't know how anyone is doing it.

[PJMack]

Nathan do you have a Micro-USB to DB9 cable? I have not tried exactly what you're doing, but the driver mentioned in the snapshot I pasted above I believe is just for enabling serial control over a USB port on a laptop. Your Global Connect device has a DB9 port, right? So it's already a serial port, I would not think it would need any special driver as long as you have the right cable to connect the two devices. Something like this perhaps: https://www.elecbee.com/en-50872-micro-usb-male-to-d-sub-9-pin-female-straight-connector-with-serial-cable-1-5m

[Wayne DeNardi]

Do you really need to use the Global Cache device and serial connection?  Couldn't you just use xAPI over websocket instead directly from whatever you have sending commands to the Global Cache?  This would remove the additional complexity of converting stuff to serial.

[nathansmith159]

Unfortunately, requirements dictate an airgap between the AV control network and the customer's LAN. The customer is going to put their network into the codec, so that means we can't. So, no websockets or SSH.

I'm really just wanting to know how anyone, at all, controls a Cisco Codec EQ using the serial interface. FWIW, I tried a DB9 -> USB-A cable with a USB-A -> Micro-USB converter and that still didn't work. 

[Wayne DeNardi · Accepted solution]

What about using the device's own internal network ports to host the device that is issuing the commands (connected to ports indicated by "G" in the diagram below)?   That way it wouldn't be on the customer's network (connected to port indicated "I").   

There is no internal connection between the two, so that would keep your air gap and stop having to use legacy serial comms.  There really isn't any way to connect to the Micro-USB port (O) from anything other than Windows/Mac/Linux where a serial port driver is required, so if you can't use a device that supports installation of a driver, you're out of luck.

[nathansmith159]

Thank you for this reply, and the confirmation that I'm not going crazy with the serial port. If it doesn't work, it doesn't work.

I'll see if the G ports being separate is separate enough for the customer.

It makes sense to me, so thanks again for the explanation and suggestion.