vaporhat or others - have you had any luck communicating with this switch via RS-232? I have the same switch and have had no luck talking with it over RS-232 using either the included control software or other terminal programs. No responses at all. I am starting to think it is the cable or some setting I am missing. I am using a female DB9 to femail DB9 that I found in my box of cables (actually have tried several that I found) in a known working serial port (used for UPS communication). I can re-solder the one cable's connections if need be but I would like know that is the problem not the switch or a setting and know the exact pinouts that I need. Has anyone been able to control this switch via RS-232 at all? Thank you!

As I said above you "need" a null modem adapter to make this work:

[Link: monoprice.com]

I wanted to post back with my experiences. I tried a null modem adapter and still had no luck with the included "Matrix" software that came with the switch. This is really where I went wrong. I assumed it was best to start with what should work - the included software - before moving on to interpreting the previously posted spec sheet PDF to determine the raw commands to send. I figured less variables in the mix. Well, the included software just doesn't work for me. I don't know if it is a Windows 7 compatiblity or what (I tried compatiblity modes). Anyway, I eventually went to Eventghost and loaded the serial plug-in. When I inputted the command sequences listed on page one of this thread and hit "Test", BAM! the switch changed inputs. This was with the standard female DB9 to female DB9 that I had been using all along - no null modem adapter and as far as I know it is not a null modem cable. Summary: when I ditched trying the included software and using a program that I knew sent the commands properly, it worked.

The Monoprice 4x4 matrix definately needs a null modem adapter - I'm using one right now hooked up to my RTI XP-8 controller.

I'd guess your female to female cable is a null modem cable, unless the 4x2 matrix is different than the 4x4 (they use the same code set, so I doubt it). If you have an ohm meter you can check it as pins 2 and 3 will be swapped across the cable.

Dino

Null modem adapter cables should be called crossover cables, while the other type of cables should be called straight thru. Equipment comes "Both ways" Some need a straight through cable and some a crossover.

The Pronto extender is a three wire device. It should not be called RS232, in fact very little of what is out there should be called "RS232" but rather "serial". RS232 is a very specific and detailed spec, not the hodgepodge that masquarades as "Serial/RS232". A three wire serial cable (about 70% of the devices use this either straight through or crossover) only has ground, transmit (Tx), and receive (Rx). There are no line (wires) for flow control or signaling. If the component needs flow control or signaling then some pins generally need to be dummied up at the component. The Pronto Extender ONLY USES Pins 2, 3, 5. There are no wires connected to any of the other pins inside the chassis

If a component uses ASCII strings for communications (not the same as hex digits) then any terminal program may be used to send/receive data. Some times the component uses an ASCII control characters (Ascii index <32 decimal) for message delimiting at which time the problem gets harder. If it is just a LF or CR or CRLF as a terminating sequence most terminal programs can handle it.

The first thing one must do when dealing with an unknown component is get the protocol spec for the device. That should spell it all out if written well (including the cable type and wiring info, and required com port settings).

My web site (my domain is the-gordons.net; if you can't figure out the website you are probably in over your head) has a downloadable archive entitled Pronto PRO Communications. I wrote it a while back because of all the problems many were having with "RS232" communications and the Pronto Pro line. Just get to the home page, look for the link to the download area and look for what should be obvious.

I will be glad to assist people with questions or issues, but I really prefer email (check my profile), but ask that you first do me the courtesy of perusing the document I referenced.

Big THANK YOU!

Update, you DO need a null modem cable:)

Also, I needed to input the command structure was a little different (I am using XLobby)
power on / off

FF 00 D5 7B

These codes are for the 4x4 matrix but I believe they are the same...?

replace the commas with a space and skip the " "

output 1:
input 1 "00,ff,d5,7b"
input 2 "01,fe,d5,7b"
input 3 "02,fd,d5,7b"
input 4 "03,fc,d5,7b"

output2:
input 1 "04,fb,d5,7b"
input 2 "05,fa,d5,7b"
input 3 "06,f9,d5,7b"
input 4 "07,f8,d5,7b"

output3:
input 1 "08,f7,d5,7b"
input 2 "09,f6,d5,7b"
input 3 "0a,f5,d5,7b"
input 4 "0b,f4,d5,7b"

output4:
input 1 "0c,f3,d5,7b"
input 2 "0d,f2,d5,7b"
input 3 "0e,f1,d5,7b"
input 4 "0f,f0,d5,7b"

Thanks to Chris from San Ramon, CA for the above, from the reviews section on Monoprice.com

Power Toggle 10 ef d5 7b

These all work via rs-232 from my RTI XP8. For discrete power, I ran the + on the power supply through a contact closure on my XP8. I created macros - for off I cut the power for 2 seconds, then restore. The matrix defaults to off. For on, I do the same, then wait 10 seconds to send the power toggle. Flawless!

I also have the 4x4 hooked up to my XP-8, no problems.

By the way, why do you need to power on/off the switcher? I just keep mine on all the time.

I sometimes have little glitches with a component-hdmi adapter not handshaking with the 4x4 properly and picture cutting in and out or the color going all wonky, but if I do a hard boot in my macro before changing to that input, it works all the time.

Hello,

I have the monoprice 4x4 HDMI Matrix. I also purchased a null modem cable. I have the cable on COM3, trying to talk to the Matrix via Putty.

I choose, Com3, 9600,8,1,n,DSR/DTR but no response from the device. I've also tried XON/XOFF and none for Flow Control.

Can't get any communication going at all. I've tried three different serial cables in case that is the issue, same result. To be sure I just purchased a NM cable from monoprice. Same problem.

I am using Windows 7 32 bit and controlling other devices via serial on that machine.

Any ideas?

Jon

I had no luck with a standard null modem cable. What worked for me was a cable with all pins straight except for pins 2 & 3 which are crossed over. This is also documented in the readme.txt file on the CD that shipped with my Monoprice switch.

-David

That is what a Null cable is, pins 2 and 3 reversed.

And pins 4 & 6 crossed and pins 7 & 8 crossed. ;-) With all these crossed I couldn't get it to work. With 2 & 3 only crossed it worked fine.

http://en.wikipedia.org/wiki/Null_modem

I control my AVatrix from the serial port on a Global Cache wifi interface. I use my ipad as the remote. Set the serial port for 9600 baud, 8 bits no parity. I used my pc as an rs232 terminal to work things out.

I just finished writing a driver for the monoprice 4x2 switcher with RS232 control.

The cable required is odd. pins 2,3 are swapped but all other pins especially 4 DTR are connected straight through.

The DTR pin is important. Without DTR on the monoprice provides no status back. RTS,CTS,DSR,CD have no effect and can be connected or disconnected, they should be wired straight through if connected.

Finally the status is continuously sent back while dtr is asserted.

If the switcher is not powered on, it still sends status back, however it won't switch. Since the status includes whether it is on/off you can look at the status and if it is off send the power toggle command 0x10, 0xEF, 0xD5, 0x7B to turn it on.