I'm trying to debug sending RS-232 commands to the DENON DBP-2010CI blu-ray player. These are going out port 9 of the primary MSC-400. I have two Neothings switchers, a DENON DVD-5910CI, an AVR-5803A and a Polk XrT12 XM receiver all working with RS-232 commands with the MSC-400. However, the DBP-2010CI is being stubborn.

Everytime I send an RS-232 command to the DBP-2010CI, the response I receive is a very solid 15h (NAK). The specs say this is the result of a communications error (overrun, framing or parity error). So, I brought up the output from the MSC-400 on the laptop and it looks fine there.

Could someone more knowledgible in RS-232 and the DBP-2010CI look at my settings/commands and tell me what I'm doing wrong?

Communications port is: 8-E-1 but I've also tried 8-N-1 with the same results. I found it funny that the specs say to use Even parity (with No parity as an option). Running at 9600.

A sample command on the URC CCP for 'Stop' looks like:

\x02A\x00\x00\x00\x00\x00\x0344

No carriage return included. Near as I can tell this matches the DENON specs.

I've updated the DBP-2010CI to the latest firmware.

What am I missing?

Thanks for any help.

I agree - there are some issues.

I have two 2500BTCI on the same job (different racks, different MSC-400), one running with parity off and CR enabled and another one with parity set to even and no CR and both work. I had to do a lot of test runs to make them work. Not sure if something is changing in design or just RS232 is so flaky in those units or MSC - Denon DVD combo. In one of the racks I have swapped MSC and the new one worked after same program was downloaded. But the same port from old one worked on another piece of equipment with no problems.
Now, once i was able to hit the right combo of settings and ports all was good from there on forever. Don't know why though.
I suggest switching port and settings. It worked for me.
As far as commands, you are fine:
\x02A\x00\x00\x00\x00\x0344 - standard DVD
\x02A\x00\x00\x00\x00\x00\x0344 - Blu-Ray and new ones (tested on 2500BTCI - don't ask).

Thanks for the information. Unfortunately, when I tried all the open ports on the master and slave MSC-400, I still couldn't get past the dreaded \x15 response.

So, for now I'll use an IR link and work on the RS-232 after I get everything else up and running. Not as slick but at least it works...(glad I got a set of jacketed IR cables for the MSC-400s)

Once I have time, one of the first things I'll try is a shorter RS-232 cable. I have to wonder if the 2500 RS-232 circuits are very very sensitive to rounded signals. I'm using a URC standard RS-232 cable but maybe the 10' is too much.

Andy

No. I have RS232 running on CAT5 for almost 100ft with no problems. In genetral RS232 works fine for 50ft and 250 on lo-cap cable but that's the standard talking. Real life figures are much more forgiving on slow speeds (like 9600).